Node. js v6.7.0 Documentación Objetos globales Estos objetos están disponibles en todos los módulos. Algunos de estos objetos no están realmente en el ámbito global sino en el ámbito del módulo - esto se notará. Los objetos enumerados aquí son específicos de Node. js. Hay una serie de objetos integrados que forman parte del propio lenguaje JavaScript, que también son accesibles a nivel mundial. Clase: Buffer Se utiliza para manejar datos binarios. Consulte la sección del búfer. Dirname El nombre del directorio en el que reside el script actualmente en ejecución. Ejemplo: ejecutar el nodo example. js desde / Users / mjr dirname isn39t en realidad es global pero es local para cada módulo. Por ejemplo, dado dos módulos: a y b. Donde b es una dependencia de a y existe una estructura de directorio de: Las referencias a dirname dentro de b. js devolverán / Users / mjr / app / nodemodules / b mientras que las referencias a dirname dentro de a. js devolverán / Users / mjr / app . Filename El nombre del archivo del código que se está ejecutando. Ésta es la ruta absoluta resuelta de este archivo de código. Para un programa principal esto no es necesariamente el mismo nombre de archivo utilizado en la línea de comandos. El valor dentro de un módulo es la ruta de acceso a ese archivo de módulo. Ejemplo: ejecutar el nodo example. js desde / Users / mjr filename isn39t en realidad es global pero bastante local para cada módulo. ClearImmediate (immediateObject) clearInterval (intervalObject) clearTimeout (timeoutObject) consola Se utiliza para imprimir en stdout y stderr. Consulte la sección de consola. Exports Una referencia al module. exports que es más corto al tipo. Consulte la documentación del sistema de módulos para obtener detalles sobre cuándo utilizar exportaciones y cuándo utilizar module. exports. Las exportaciones no son en realidad globales sino locales para cada módulo. Global En los navegadores, el ámbito de mayor nivel es el ámbito global. Esto significa que en los navegadores si estás en el ámbito global var algo definirá una variable global. En Node. js esto es diferente. El ámbito de nivel superior no es el ámbito global var algo dentro de un módulo Node. js será local para ese módulo. Módulo Una referencia al módulo actual. En particular module. exports se utiliza para definir lo que un módulo exporta y hace disponible a través de require (). Módulo isn39t realmente un global pero bastante local a cada módulo. Process El objeto de proceso. Consulte la sección del objeto de proceso. Require () Requerir módulos. Consulte la sección Módulos. Requieren isn39t realmente un global pero algo local a cada módulo. Require. cache Los módulos se almacenan en caché en este objeto cuando son necesarios. Al eliminar un valor de clave de este objeto, el siguiente requerirá volver a cargar el módulo. Tenga en cuenta que esto no se aplica a complementos nativos. Para lo cual la recarga resultará en un Error. Require. extensions Instruir require sobre cómo manejar ciertas extensiones de archivo. Procesar archivos con la extensión. sjs como. js: Deprecated En el pasado, esta lista se ha utilizado para cargar módulos que no son JavaScript en Node. js compilándolos bajo demanda. Sin embargo, en la práctica, hay maneras mucho mejores de hacerlo, como cargar módulos a través de algún otro programa Node. js o compilarlos a JavaScript antes de tiempo. Dado que el sistema Module está bloqueado, esta función probablemente nunca desaparecerá. Sin embargo, puede tener bugs sutiles y complejidades que mejor se dejan sin tocar. Require. resolve () Utilice la maquinaria internal require () para buscar la ubicación de un módulo, pero en lugar de cargar el módulo, simplemente devuelva el nombre de archivo resuelto. Gracias a la brillante labor de Ryan Dahl, tenemos node. js, un hermoso y elegante framework de servidor integrado en la parte superior del motor Javascript de V8 de Google39s (callback, arg.) SetInterval (callback, delay, arg. Esto abre un nuevo mundo de posibilidades para el desarrollo de aplicaciones web, APIs y servidores HTTP ligeros. Cada semana tendremos una discusión de grupo sobre un aspecto particular de NodeJS, o un whackiest. En esta charla relámpago, Aidan Feldman demuestra un prototipo que construyó para manipular objetos 3D virtuales usando un dispositivo móvil. El manejo de gestos en un teléfono generalmente significa tapping, swiping, etc., pero todos estos se limitan al plano / área 2D de la pantalla. El uso del movimiento del teléfono mismo abre nuevas dimensiones para las interfaces gestuales. Con un dispositivo móvil (gyro-enabled) y un modelo 3D en la computadora, este proyecto pasa los datos de orientación del dispositivo desde el teléfono a la pantalla a través de websockets, ajustando el modelo en tiempo real. GitHub Repo para el proyecto aquí. Esta charla fue presentada en el encuentro de NodeJS en Spotify en Nueva York. Autor desconocido el 3 de diciembre de 2014 Stefan Kutko, VP de Ingeniería en Electronifie. Presenta lo que su equipo ha aprendido mientras que la construcción de lo que es muy probable la primera plataforma de comercio electrónico de bonos escrito en Node. js. Él cubre cómo Electronifie utiliza mensajería y microservicios para construir su sistema distribuido, permitiendo que los dominios del problema sean separados por el servicio y cada servicio sea personalizado adaptado al problema que resuelve. En el camino, Stefan muestra cómo una arquitectura CQRS (Command Query Responsibility Separation) permite que su sistema se amplíe y cómo patrones como Event Sourcing permiten beneficios interesantes para aplicaciones financieras. Mezclado en será vislumbres de cómo Electronifie está respirando aire fresco en FinTech mediante el uso y contribución a Open Source, además de aspersiones de Meteor, complementos binarios y habilitar el escritorio Node. js web apps Diapositivas están disponibles aquí. Esta charla fue presentada en el encuentro de NodeJS en Spotify en Nueva York. Rich Harris (desarrollador de front end en The Guardian y creador de RactiveJS) nos lleva a un viaje de por qué y cómo creó la herramienta de construcción Gobble. Cómo ampliarlo y cómo utilizarlo en sus proyectos. Puesto que Grunt. js encendió el camino a una manera más elegante de trabajar, theres sido una explosión de las herramientas de la construcción basadas en node. js - Gulp, Plumber, Assetgraph y bróculi, por nombrar algunos. Cada uno trae algo único a la mesa. Teniendo en cuenta todas estas opciones, por qué necesitamos otro Gobble está optimizado para la sanidad del desarrollador? Prioriza la depuración, la facilidad de uso y un enfoque basado en estándares para crear complementos. Esta charla explora porqué estas cosas son tan importantes, y cómo Gobble trabaja debajo de la capilla para entregar las construcciones ardientes rápidas. Esta charla fue organizada por el meetup de nodejs en Shutterstock en Nueva York. Brad Oyler. Desarrollador principal de NBC News. Habla sobre la transición que ayudó a guiar para mover NBCNews a Node. js. Él cubre qué retos enfrentaron y qué mejores prácticas encontraron en el proceso. Brad también sugiere cuándo (y NO) querría usar NodeJS para un sitio de contenido, así como cómo probar mejor su implementación. Esta charla fue organizada por el meetup de nodejs en Shutterstock en Nueva York. WebRTC es un proyecto abierto y gratuito que permite a los navegadores web con capacidades de comunicaciones en tiempo real (RTC) a través de simples API de JavaScript. Arin Sime (CEO y fundador de AgilityFeat) explica cómo integrar WebRTC y mensajería en tiempo real en una aplicación Node. js. Él demos y aplicación simple para mostrar tanto chat de vídeo y otras características en tiempo real. Esta charla fue dada en la reunión de nodejs organizada por Shutterstock en Nueva York. Jarrett Cruger (Ingeniero de Software, Nodejitsu) discute casos prácticos de uso de Godot, un procesador de eventos en tiempo real de streaming basado en Riemann escrito en Node. js. Echa un vistazo a esta charla si estás interesado en monitoreo, mensajería, registro interno y recopilación de datos de métricas. Esta charla fue dada en el NodeJS Meetup organizado por Shutterstock en Nueva York. Ben Newman (Ingeniero, Facebook) ha pasado muchos meses creando Regenerator. El proyecto de código abierto brinda soporte para generadores de estilo ES6 a su código. En esta charla popular, Ben hablará de lo que lo llevó a crear Regenerator, nos mostrará lo que puede hacer hoy, y le dará un pico de lo que va en el futuro. Esta charla fue presentada en la reunión de nodejs alojada por Pivotal Labs. Si usted está construyendo una nueva aplicación web, los problemas que se ejecutan en general encajan en una de las cuatro categorías: 1) Prototipos: Quiero construir algo rápidamente. 2) Adaptación: Quiero ser capaz de iterar fácilmente en mi base de código. 3) Pruebas: Quiero asegurarme de que la aplicación funcione. 4) Escala: Quiero utilizar recursos del servidor eficientemente. En su presentación, Valeri Karpov de MongoDB proporcionará una visión general de alto nivel de cómo la pila MEAN, y en particular Node. js y npm, resuelven cada uno de estos puntos de dolor. Esta charla fue grabada en la reunión de node. js en Pivotal Labs. Esta charla fue grabada en la reunión de NodeJS en Pivotal Labs. Los datos conectados abundan hoy. Los servicios web modernos conectan personas, productos, fotos, ubicaciones, ideas, creaciones y más. Han surgido nuevas herramientas que están optimizadas para esta conexión y las bases de datos de gráficos son una de esas herramientas. En lugar de trabajar con tablas y filas, trabaja con nodos y aristas almacenando datos exactamente como lo dibujaría en una pizarra. En esta charla de la reunión de nodejs en Nueva York, Aseem Kishore compartirá una introducción a Neo4j, la base de datos de gráficos más popular, junto con sus experiencias y lecciones aprendidas construyendo un inicio en la parte superior de la misma. Aseem es el coautor y mantenedor de node-neo4j, la biblioteca cliente de Node. js para Neo4j, así que el infierno también camina a través de los fundamentos de usar Neo4j con Node. js. Aseems diapositivas de la charla están aquí. Su navegador no admite el elemento de audio. Aleksandr Yampolskiy. CTO de Cinchcast y BlogTalkRadio. Y su colega Danny Gershman presentará Sharing Slides con 10,000 personas en r / t: Socket. IO y Node. JS en producción en esta grabación de la reunión de NYC Node. JS. Cubren consejos sobre seguridad y muestran cómo se acercaron a asegurar su aplicación. Esta tecnología habla cubre asegurar Node. js amp Socket. io en producción. Su navegador no admite el elemento de audio. Hakka Labs conecta ingenieros de software y científicos de datos en torno a desafíos comunes utilizando tecnologías de datos de código abierto. Nuestro contenido, programas de capacitación y eventos están diseñados para proporcionar a los ingenieros el conocimiento y conocimientos para crear sistemas escalables y analíticos para manejar cantidades cada vez mayores de datos. Más información NYC 33 W 17th Street, 4th floor Nueva York, NY 10011 SF 44 Tehama San San Francisco, CA 94105Interactive Brokers API addon para Node. js compatible con IB API 9.71 Este complemento utiliza la última API Interactive Brokers POSIX C estable. Autor: Jae Yang - dchem (keybase. io/dchem) Los mensajes de entrada están en el orden en que fueron recibidos. Además, los mensajes salientes están limitados a 50 msg / seg como IB lo requiere. El comportamiento predeterminado es que si su tasa de salida es mayor que el 51º mensaje será manejado en el siguiente segundo. Si desea ver el jsdoc de este proyecto, simplemente ejecútelo en el archivo ibapi. js. El mensaje de servidor messageId ha cambiado de svrError al error YYYY-MM-DD - SEMVER - Notas 2015-11-21 - 2.4.0 - Corrección del manejo de mensajes de error del servidor 2015-06-27 - 2.3.3 - Fixes build (remove sourceforge) 2015- 06-09 - 2.3.1 - Cambiado a SEMVER, la descarga anterior debería usar OldVer. 2015-03-01 - 2.3.0 - Nodo 0.12 amp io. js 1.4.2 build compatible. Limpieza de código y ejemplos actualizados. 2015-01-07 - 2.2.0 - Más eficiente de la CPU 2014-12-29 - 2.1.0 - Utiliza controladores de eventos en lugar de emisores de eventos 2014-11-12 - 1.23.0 - Incluye lib en el propio paquete 2014-09- 10 - 1.21.0 - Soporta API 9.71 2014-09-09 - 1.19.0 - Agrega order. js y placeOrder puede utilizar order obj 2014-04-22 - 1.17.0 - Corrección de compatibilidad para API 9.70 2014-03-17 - 1.13.0 - Instalación más fluida a múltiples sistemas operativos 2014-01-17 - 1.0.0 - todos los eventos de EWrapper enlazados en ibapi. js 2013-09-02 - 0.0.0 - Comando inicial Instalar descomprimir si Linux instala MinGW Instala msys-unzip en su lugar De unzip Instalar msys-wget Instalar Microsoft Visual Studio Para Windows con MSVS 2013: Para Windows con MSVS 2012: Como alternativa, incluya GYPMSVSVERSION2012 o GYPMSVSVERSION2013 en variables de entorno para Windows. Instalar las herramientas de línea de comandos de xcode Instalar homebrew Instalar wget a través de homebrew Asegúrese de tener instalado nodo-gyp Ejecute preinstall. sh que hace lo siguiente: Descargue la última API IB establecida en / import Copie el contenido de IB API packageaposs IBJts / source / PosixClient / Directorio de entrada / importación compartido Copie el contenido de IB API packageaposs IBJts / source / PosixClient / src en / directorio de importación Añadir define IBUSESTDSTRING en los siguientes archivos en / import directorio: EClientSocketBase. cpp EPosixClientSocket. cpp Descargas libjson 7.6.1 node-gyp Reconstruir Si la compilación falla porque tiene VS2012, use node-gyp --msvsversion2012 rebuild Requerir ibapi Crear manejadores de eventos Registrar manejadores de eventos para messageIds Invoke connect (). Beneficio Se utilizan como almacenes de estado y abstracción para IB API. También tiene que pasar instancia del objeto, como aposorderapos a algunas de las funciones de solicitud del cliente. Cada uno de ellos viene con un constructor: orden de ejecución del contrato escánerSubscripción contratoDetails beginProcessing (). Punto de entrada: inicia el procesamiento del mensaje. DoAction (acción). Una acción, una función personalizada o solicitudes de API, se pueden vincular a cada evento placeSimpleOrder (). Método de entrada de orden más simple. ProcessMsg (). Msg procesador - una implementación POSIX del controlador de mensajes de red. Esto no necesita ser llamado explícitamente por el usuario Los comandos siguientes se utilizan para solicitar una acción específica a través de la API de IB: Por qué el infierno usaría Node. js? Tutorial de caso por caso Introducción La creciente popularidad de JavaScripts ha traído consigo una gran cantidad de Cambios, y la cara del desarrollo web de hoy es dramáticamente diferente. Las cosas que podemos hacer en la web hoy en día con JavaScript que se ejecuta en el servidor, así como en el navegador, eran difíciles de imaginar hace sólo varios años, o fueron encapsulados en entornos de caja de seguridad como Applets Flash o Java. Antes de excavar en Node. js. Es posible que desee leer sobre las ventajas de usar JavaScript en la pila que unifica el idioma y el formato de datos (JSON), lo que le permite optimizar la reutilización de los recursos del desarrollador. Como esto es más un beneficio de JavaScript que de Node. js específicamente, no lo discutiremos mucho aquí. Pero es una ventaja clave para incorporar Node en tu stack. Como Wikipedia dice: Node. js es una compilación empaquetada del motor JavaScript de Googles V8, la capa de abstracción de la plataforma libuv y una librería central, que está escrita principalmente en JavaScript. Más allá de eso, vale la pena señalar que Ryan Dahl, el creador de Node. js, tenía como objetivo crear sitios web en tiempo real con capacidad de empuje. Inspirado en aplicaciones como Gmail. En Node. js, le dio a los desarrolladores una herramienta para trabajar en el paradigma de E / S sin bloqueo, impulsado por eventos. Después de más de 20 años de apátridas-web basado en el paradigma de solicitud-respuesta sin estado, finalmente tenemos aplicaciones web con conexiones bidireccionales en tiempo real. En una frase: Node. js brilla en aplicaciones web en tiempo real que emplean tecnología push a través de websockets. Bueno, después de más de 20 años de apátridas basado en el paradigma de solicitud-respuesta sin estado, finalmente tenemos aplicaciones web con conexiones bidireccionales en tiempo real, donde tanto el cliente como el servidor pueden iniciar la comunicación, Permitiéndoles intercambiar datos libremente. Esto está en marcado contraste con el típico paradigma de respuesta web, donde el cliente siempre inicia la comunicación. Además, todo está basado en la pila web abierta (HTML, CSS y JS) que se ejecuta sobre el puerto estándar 80. Uno podría argumentar que hemos tenido esto durante años en forma de Applets Flash y Java, pero en realidad, La web como un protocolo de transporte para ser entregado al cliente. Además, se ejecutaban en aislamiento ya menudo operaban sobre puertos no estándar, lo que puede haber requerido permisos adicionales y tal. Con todas sus ventajas, Node. js ahora juega un papel crítico en la pila de tecnología de muchas empresas de alto perfil que dependen de sus beneficios únicos. En este post, discutiré no sólo cómo se logran estas ventajas, sino también por qué es posible que desee utilizar Node. jsand por qué no usar algunos de los modelos clásicos de aplicaciones web como ejemplos. Cómo funciona La idea principal de Node. js: utilizar E / S sin bloqueo y eventos para mantenerse ligero y eficiente frente a las aplicaciones en tiempo real que utilizan datos intensivos que se ejecutan a través de dispositivos distribuidos. Eso es un bocado. Lo que realmente significa es que Node. js no es una nueva plataforma de plata-bala que dominará el mundo del desarrollo web. En su lugar, es una plataforma que llena una necesidad particular. Lo que realmente significa es que Node. js no es una nueva plataforma de plata-bala que dominará el mundo del desarrollo web. En su lugar, es una plataforma que llena una necesidad particular. Y entender esto es absolutamente esencial. Usted definitivamente no quiere utilizar Node. js para las operaciones de uso intensivo de la CPU de hecho, el uso de él para el cálculo pesado anulará casi todas sus ventajas. Donde Node realmente brilla es en la construcción de aplicaciones de red rápidas y escalables, ya que es capaz de manejar un gran número de conexiones simultáneas con alto rendimiento, lo que equivale a una alta escalabilidad. Cómo funciona bajo el capó es bastante interesante. En comparación con las técnicas tradicionales de servicio web en las que cada conexión (petición) genera un nuevo subproceso, que ocupa la RAM del sistema y eventualmente maximiza la cantidad de RAM disponible, Node. js opera en un solo hilo, S, lo que le permite soportar decenas de miles de conexiones simultáneas (mantenidas en el bucle de eventos). Un cálculo rápido: suponiendo que cada hilo potencialmente tiene un acompañamiento de 2 MB de memoria con él, que se ejecuta en un sistema con 8 GB de RAM nos pone en un máximo teórico de 4000 conexiones simultáneas, además del costo de cambio de contexto entre hilos. Ese es el escenario que normalmente se ocupan en las técnicas tradicionales de servicio web. Al evitar todo esto, Node. js logra niveles de escalabilidad de más de 1 M conexiones concurrentes (como una prueba de concepto). Hay, por supuesto, la cuestión de compartir un único hilo entre todas las solicitudes de los clientes, y es una trampa potencial de escribir aplicaciones Node. js. En primer lugar, la computación pesada podría ahogar nodos de hilo único y causar problemas para todos los clientes (más sobre esto más adelante) como las solicitudes de entrada se bloqueó hasta que dicho cálculo se completó. En segundo lugar, los desarrolladores deben tener mucho cuidado de no permitir que una excepción borre hasta el bucle de eventos Node. js de núcleo (superior), lo que hará que la instancia de Node. js termine (bloqueando eficazmente el programa). La técnica utilizada para evitar las excepciones borboteando hasta la superficie es devolver errores al llamador como parámetros de devolución de llamada (en lugar de lanzarlos, como en otros entornos). Incluso si alguna excepción no tratada logra burbujear, existen múltiples paradigmas y herramientas disponibles para supervisar el proceso del Nodo y realizar la recuperación necesaria de una instancia bloqueada (aunque no será capaz de recuperar sesiones de usuarios), siendo el más común el módulo Forever . O un enfoque diferente con las herramientas del sistema externo upstart y monit. NPM: El gestor de paquetes de nodos Al discutir Node. js, una cosa que definitivamente no debe omitir es la compatibilidad integrada para la administración de paquetes utilizando la herramienta NPM que viene por defecto con cada instalación de Node. js. La idea de los módulos de NPM es bastante similar a la de Ruby Gems. Un conjunto de componentes reutilizables disponibles públicamente, disponibles a través de una instalación fácil a través de un repositorio en línea, con administración de versiones y dependencias. Se puede encontrar una lista completa de los módulos empaquetados en el sitio web de NPM npmjs. org/. O se accede mediante la herramienta NPM CLI que se instala automáticamente con Node. js. El ecosistema de módulos está abierto a todos y cualquiera puede publicar su propio módulo que aparecerá en el repositorio de NPM. Una breve introducción a NPM (un poco antigua, pero aún válida) se puede encontrar en howtonode. org/introduction-to-npm. Algunos de los módulos NPM más populares de hoy son: express - Express. js, un framework de desarrollo web inspirado en Sinatra para Node. js, y el estándar de facto para la mayoría de las aplicaciones de Node. js que hay hoy en día. Connect - Connect es una estructura de servidor HTTP extensible para Node. js, proporcionando una colección de complementos de alto rendimiento conocidos como middleware que sirven como base de base para Express. Socket. io y sockjs - Componente del lado del servidor de los dos componentes websockets más comunes que existen hoy en día. Jade - Uno de los motores de plantillas más populares, inspirado en HAML, un valor predeterminado en Express. js. Mongo y mongojs - Envoltorios MongoDB para proporcionar la API para bases de datos de objeto MongoDB en Node. js. Redis - Redis biblioteca de clientes. Coffee-script - El compilador de CoffeeScript que permite a los desarrolladores escribir sus programas Node. js usando Coffee. Subrayado (lodash. Lazy) - La biblioteca de utilidades más popular en JavaScript, empaquetada para ser utilizada con Node. js, así como sus dos contrapartes, que prometen un mejor rendimiento tomando un enfoque de implementación ligeramente diferente. Forever - Probablemente la utilidad más común para asegurar que una secuencia de comandos de nodo dada se ejecute continuamente. Mantiene el proceso de Node. js en producción ante cualquier fallo inesperado. La lista continua. Hay toneladas de paquetes realmente útiles por ahí, disponibles para todos (sin ofender a los que he omitido aquí). Ejemplos de dónde debe usarse Node. js CHAT Chat es la aplicación más común en tiempo real y multiusuario. Desde IRC (en el día), a través de muchos protocolos propietarios y abiertos que se ejecutan en puertos no estándar, a la capacidad de implementar todo hoy en Node. js con websockets que se ejecutan sobre el puerto estándar 80. La aplicación de chat es realmente el dulce - Ejemplo de punto para Node. js: es una aplicación ligera, de alto tráfico, de datos intensivos (pero de bajo procesamiento / cálculo) que se ejecuta a través de dispositivos distribuidos. También es un gran caso de uso para aprender también, ya que es simple, pero cubre la mayoría de los paradigmas que usará en una aplicación típica de Node. js. Vamos a tratar de describir cómo funciona. En el ejemplo más simple, tenemos una única sala de chat en nuestro sitio web donde la gente viene y puede intercambiar mensajes de uno a muchos (en realidad todos) la moda. Por ejemplo, digamos que tenemos tres personas en el sitio web todas conectadas a nuestro foro de mensajes. En el lado del servidor, tenemos una simple aplicación Express. js que implementa dos cosas: 1) un manejador GET / request que sirve la página web que contiene tanto un tablero de mensajes como un botón Send para inicializar la entrada de nuevo mensaje, y 2) un websockets Servidor que escucha los nuevos mensajes emitidos por los clientes websocket. En el lado del cliente, tenemos una página HTML con un par de manejadores configurados, uno para el evento de clic de botón de envío, que recoge el mensaje de entrada y lo envía por el websocket, y otro que escucha los nuevos mensajes entrantes en el Cliente de websockets (es decir, mensajes enviados por otros usuarios, que el servidor ahora quiere que el cliente muestre). Cuando uno de los clientes envía un mensaje, heres lo que sucede: El navegador captura el botón Enviar clic a través de un controlador de JavaScript, recoge el valor del campo de entrada (es decir, el texto del mensaje) y emite un mensaje websocket usando el cliente websocket conectado a Nuestro servidor (inicializado en la inicialización de la página web). El componente del lado del servidor de la conexión websocket recibe el mensaje y lo reenvía a todos los demás clientes conectados mediante el método de difusión. Todos los clientes reciben el nuevo mensaje como un mensaje push a través de un componente websockets del cliente que se ejecuta dentro de la página web. A continuación, recoger el contenido del mensaje y actualizar la página web en el lugar mediante la adición del nuevo mensaje a la Junta. Este es el ejemplo más simple. Para una solución más robusta. Puede utilizar una caché simple basada en la tienda Redis. O en una solución aún más avanzada, una cola de mensajes para manejar el enrutamiento de mensajes a clientes y un mecanismo de entrega más robusto que puede cubrir pérdidas de conexión temporal o almacenar mensajes para clientes registrados mientras están desconectados. Sin embargo, independientemente de las mejoras que realice, Node. js seguirá funcionando bajo los mismos principios básicos: reaccionar a eventos, gestionar muchas conexiones simultáneas y mantener la fluidez en la experiencia del usuario. API ENCIMA DE UN OBJETO DB Aunque Node. js realmente brilla con aplicaciones en tiempo real, es bastante natural para exponer los datos de DB de objetos (por ejemplo, MongoDB). Los datos almacenados JSON permiten que Node. js funcione sin la diferencia de impedancia y la conversión de datos. Por ejemplo, si está utilizando Rails, debería convertir de JSON a modelos binarios y luego volver a exponerlos como JSON a través del HTTP cuando los datos son consumidos por Backbone. js, Angular. js, etc. o incluso llamadas jQuery AJAX normales. Con Node. js, simplemente puede exponer sus objetos JSON con una API REST para que el cliente consuma. Además, no necesita preocuparse por la conversión entre JSON y cualquier otra cosa cuando lea o escriba de su base de datos (si está usando MongoDB). En resumen, puede evitar la necesidad de múltiples conversiones utilizando un formato de serialización de datos uniforme en el cliente, el servidor y la base de datos. ENTRADAS QUEUAD Si está recibiendo una gran cantidad de datos concurrentes, su base de datos puede convertirse en un cuello de botella. Como se muestra arriba, Node. js puede manejar fácilmente las conexiones simultáneas. Pero como el acceso a la base de datos es una operación de bloqueo (en este caso), nos encontramos con problemas. La solución es reconocer el comportamiento de los clientes antes de que los datos se escriban realmente en la base de datos. Con ese enfoque, el sistema mantiene su capacidad de respuesta bajo una carga pesada, lo cual es particularmente útil cuando el cliente no necesita confirmación firme de la correcta escritura de datos. Ejemplos típicos incluyen: el registro o escritura de datos de seguimiento de usuarios, procesados en lotes y no utilizados hasta un momento posterior, así como operaciones que no necesitan ser reflejadas instantáneamente (como actualizar un cuenta de Facebook en Facebook) donde la consistencia eventual Utilizado en el mundo NoSQL) es aceptable. Los datos se ponen en cola a través de algún tipo de almacenamiento en caché o de la infraestructura de colas de mensajes (por ejemplo, RabbitMQ, ZeroMQ) y se digieren mediante un proceso de proceso por lotes de base de datos independiente o servicios de procesamiento intensivos de procesamiento, escritos en una plataforma de mejor desempeño para dichas tareas. Un comportamiento similar se puede implementar con otros lenguajes / frameworks, pero no en el mismo hardware, con el mismo alto y mantenido rendimiento. En pocas palabras: con Node, puedes empujar la base de datos escribe a un lado y tratar con ellos más tarde, procediendo como si tuvieran éxito. DATA STREAMING En las plataformas web más tradicionales, las solicitudes HTTP y las respuestas se tratan como un evento aislado de hecho, theyre realmente arroyos. Esta observación se puede utilizar en Node. js para crear algunas características interesantes. Por ejemplo, es posible procesar archivos mientras están siendo subidos, ya que los datos entran a través de un flujo y podemos procesarlo de una manera en línea. Esto podría hacerse para la codificación de audio o video en tiempo real. Y la representación entre diferentes fuentes de datos (ver sección siguiente). PROXY Node. js se emplea fácilmente como un proxy del lado del servidor donde puede manejar una gran cantidad de conexiones simultáneas de una manera no bloqueante. Su especialmente útil para la representación de diferentes servicios con diferentes tiempos de respuesta, o la recopilación de datos de múltiples puntos de origen. Un ejemplo: considere una aplicación del lado del servidor que se comunica con recursos de terceros, extrae datos de fuentes diferentes o almacena activos como imágenes y videos en servicios cloud de terceros. Aunque existen servidores proxy dedicados, el uso de Node puede resultar útil si su infraestructura de proxy es inexistente o si necesita una solución para el desarrollo local. Con esto, quiero decir que podría crear una aplicación de cliente con un servidor de desarrollo Node. js para los activos y las solicitudes API de proxy / stubbing, mientras que en la producción youd manejar dichas interacciones con un servicio de proxy dedicado (nginx, HAProxy, etc.) . BROKERAGE - STOCK TRADERS DASHBOARD Permite volver al nivel de aplicación. Otro ejemplo en el que domina el software de escritorio, pero que podría ser fácilmente reemplazado por una solución web en tiempo real es el software de comercio de corredores, utilizado para rastrear los precios de las acciones, realizar cálculos y análisis técnicos y crear gráficos. Cambiar a una solución basada en la web en tiempo real permitiría a los corredores cambiar fácilmente estaciones de trabajo o lugares de trabajo. Pronto, podríamos comenzar a verlos en la playa en la Florida. O Ibiza. O Bali. MONITORIZACIÓN DE LA APLICACIÓN DEL SALTO DE INSTRUMENTOS Otro caso de uso común en el que Node-with-web-sockets encaja perfectamente: seguimiento de los visitantes del sitio web y visualización de sus interacciones en tiempo real. (Si está interesado, esta idea ya está siendo producida por Hummingbird.) Usted podría reunir estadísticas en tiempo real de su usuario, o incluso moverlo al siguiente nivel mediante la introducción de interacciones específicas con sus visitantes mediante la apertura de un canal de comunicación cuando lleguen Un punto específico en su embudo. Imagínese cómo podría mejorar su negocio si supiera lo que sus visitantes estaban haciendo en tiempo real, si pudiera visualizar sus interacciones (si está interesado, esta idea ya está siendo producida por CANDDi). Con los sockets de Node. js de dos vías en tiempo real, ahora puede hacerlo. SISTEMA DE SEGUIMIENTO DEL TABLERO DE INSTRUMENTOS Ahora, vamos a visitar el lado de la infraestructura de las cosas. Imagine, por ejemplo, un proveedor de SaaS que desee ofrecer a sus usuarios una página de supervisión de servicios (por ejemplo, la página de estado de GitHubs). Con el bucle de eventos Node. js, podemos crear un potente panel de control basado en web que comprueba los estados de los servicios de forma asincrónica y empuja los datos a los clientes mediante websockets. Tanto los estados internos (intra-empresa) como los servicios públicos pueden ser reportados en vivo y en tiempo real utilizando esta tecnología. Empuje esa idea un poco más e intente imaginar las aplicaciones de monitoreo del Network Operations Center (NOC, por sus siglas en inglés) en un operador de telecomunicaciones, proveedor de cloud / network / hosting, o alguna institución financiera, todas ejecutadas en la web abierta respaldada por Node. js y websockets En lugar de Java y / o Applets Java. Nota: No trate de construir sistemas duros en tiempo real en Nodo (es decir, sistemas que requieran tiempos de respuesta consistentes). Erlang es probablemente una mejor opción para esa clase de aplicación. Donde se puede usar Node. js APLICACIONES WEB DEL SERVIDOR Node. js con Express. js también se puede usar para crear aplicaciones web clásicas en el servidor. Sin embargo, aunque sea posible, este paradigma petición-respuesta en el que Node. js llevaría alrededor de HTML representado no es el caso de uso más típico. Hay argumentos a favor y en contra de este enfoque. Aquí hay algunos datos a tener en cuenta: Si su aplicación no tiene ninguna CPU de computación intensiva, puede construir en Javascript de arriba a abajo, incluso hasta el nivel de base de datos si se utiliza el almacenamiento de objetos JSON DB como MongoDB. Esto facilita el desarrollo (incluyendo la contratación) de manera significativa. Los rastreadores reciben una respuesta HTML totalmente renderizada, que es mucho más SEO-friendly que, por ejemplo, una aplicación de página única o una aplicación de websockets ejecutada en la parte superior de Node. js. Cualquier CPU de computación intensiva bloqueará la capacidad de respuesta de Node. js, por lo que una plataforma de subprocesos es un enfoque mejor. Alternativamente, podría intentar escalar el cálculo. El uso de Node. js con una base de datos relacional es todavía bastante doloroso (ver más abajo para más detalles). Hazte un favor y recoger cualquier otro entorno como Rails, Django o ASP MVC si estás intentando realizar operaciones relacionales. An alternative to these CPU intensive computations is to create a highly scalable MQ-backed environment with back-end processing to keep Node as a front-facing clerk to handle client requests asynchronously. Where Node. js Shouldnt Be Used SERVER-SIDE WEB APPLICATION W/ A RELATIONAL DB BEHIND Comparing Node. js with Express. js against Ruby on Rails, for example, there is a clean decision in favour of the latter when it comes to relational data access. Relational DB tools for Node. js are still in their early stages theyre rather immature and not as pleasant to work with. On the other hand, Rails automagically provides data access setup right out of the box together with DB schema migrations support tools and other Gems (pun intended). Rails and its peer frameworks have mature and proven Active Record or Data Mapper data access layer implementations, which youll sorely miss if you try to replicate them in pure JavaScript. Still, if youre really inclined to remain JS all-the-way (and ready to pull out some of your hair), keep an eye on Sequelize and Node ORM2 both are still immature, but they may eventually catch up. Its possible and not uncommon to use Node solely as a front-end, while keeping your Rails back-end and its easy-access to a relational DB. HEAVY SERVER-SIDE COMPUTATION/PROCESSING When it comes to heavy computation, Node. js is not the best platform around. No, you definitely dont want to build a Fibonacci computation server in Node. js. In general, any CPU intensive operation annuls all the throughput benefits Node offers with its event-driven, non-blocking I/O model because any incoming requests will be blocked while the thread is occupied with your number-crunching. As stated previously, Node. js is single-threaded and uses only a single CPU core. When it comes to adding concurrency on a multi-core server, there is some work being done by the Node core team in the form of a cluster module ref: nodejs. org/api/cluster. You can also run several Node. js server instances pretty easily behind a reverse proxy via nginx . With clustering, you should still offload all heavy computation to background processes written in a more appropriate environment for that, and having them communicate via a message queue server like RabbitMQ. Even though your background processing might be run on the same server initially, such an approach has the potential for very high scalability. Those background processing services could be easily distributed out to separate worker servers without the need to configure the loads of front-facing web servers. Of course, youd use the same approach on other platforms too, but with Node. js you get that high reqs/sec throughput weve talked about, as each request is a small task handled very quickly and efficiently. Conclusion Weve discussed Node. js from theory to practice, beginning with its goals and ambitions, and ending with its sweet spots and pitfalls. When people run into problems with Node, it almost always boils down to the fact that blocking operations are the root of all evil 99 of Node misuses come as a direct consequence. In Node, blocking operations are the root of all evil99 of Node misuses come as a direct consequence. Remember: Node. js was never created to solve the compute scaling problem. It was created to solve the I/O scaling problem, which it does really well . Why use Node. js If your use case does not contain CPU intensive operations nor access any blocking resources, you can exploit the benefits of Node. js and enjoy fast and scalable network applications. Welcome to the real-time web. About the author View full profile raquo member since February 12, 2013 Tomislav is a software engineer, technical consultant, and architect with over 10 years of experience. He specializes in full-stack, highly scalable, real-time JavaScript and Node. js applications, with past experience in C, Java, and Ruby. He is an agile Kanban practitioner who loves to collaborate on development projects. click to continue. Comments For relational DBs on Node, I like bookshelfjs. org/ Awesome article I definitely agree that node. js has some really perfectly suited use cases. However, I do want to comment on something that is a bit of a pet peeve of mine -- I wish you wouldn39t contrast it with a non-existent straw-man quottraditionalquot system in quothow it worksquot. 1) No server spawns a thread per request (they use thread pools or process pools). 2) You say quotcost of context switchingquot as if it only applies to OS threads. Userspace frames need to be saved and loaded in the same way. Plus the OS does it with a few instructions, leveraging specialized support from the hardware -- which userspace can39t do. 3) Similarly, userspace threads (I. e. frames or closures if you don39t want to talk threads) take memory resources in the same way kernel threads do. It39s not as if each system thread has it39s full stack limit allocated, so that39s an unfair analysis. Normal systems regularly have more than 4000 without coming anywhere near where you39ve pegged it. 4) The BIG problem with single-thread concurrency is the lack of parallelism. Sure, you can handle thousands of requests per second, but only one CPU on your 40 core server is going to doing ANY work. Anyways, all the above is in regard to a pretty minor paragraph in your excellent post. Node isn39t really guilty of this, it39s just that there39s a lot of FUD out there around threads and processes which people often use to justify insane designs (and avoid threads when they are completely the right approach for the majority of situations). All your advice about computation heavy apps could not be more wrong. It39s certainly true that attempting heavy computation inline with the request-response cycle, is a bad idea, but the same could be said of threaded environments. If you have CPU bound operations, it39s a good idea to handle them with worker processes. JavaScript, and Node in particular are actually very well suited to handle distributed computation - especially with the good support for functional style programming. If you write your algorithms using pure functions and distribute workload to workers, you can easily distribute your workload over networked clusters. Node39s great support for networking makes it an ideal environment both for computing and orchestration tasks, and it39s orders of magnitude faster than Ruby at both. Very helpful. Thanks a lot You certainly don39t want to block any Node. js process that is handling server requests, but that doesn39t mean you shouldn39t do heavy computations behind a Node. js server. So long as the process doing the heavy computations is spawned asynchronously from your server process. Still you could end up blocking your Node. js process if you overdue it, but that is also true with the traditional threaded server. This is going to make me out to be a giant noob but can you give me an example of a quotblocking operationquot Any such hybrid system I39m thinking: Use Node. js to process a request by simply placing it onto a to-process queue, return a message to the client stating something like quotcalculating. quot. Then Node. js is free to continue with the next request. The to-process queue can then be run through using a difference thread (or even multiple threads). As and when these complete, they send their results to Node. js39s queue which will then relay it back to the original client Of course this means some ID key needs to accompany each item in this queue to ensure the correct data is returned to the correct client. Anything like this possible Or even already implemented Great article, thanks :) Tomislav, thanks for this very well written and concise article. We 39ve been using MongoDB and Node. js (in combination with AngularJS for the user facing part) for gt 2 years now and couldn39t imagine to ever, ever, ever switch back to Flash (after 10 years of experience) or JEE / RDMS. So it boils down to just one programming language (JS), one data format (JSON) and one programming paradigma (Async), wow. That39s by far the best explanation out there about Node. js. I finally understood that it is very useful (in certain scenarios) and not just a hype. Thanks a lot this was very informative Node works well with relational databases, just don39t use an ORM. SQL isn39t that hard to learn. ) True that, but I thought we as an industry got over the idea of writing all the SQL manually. Tools are good for common operations, tools that just get out of the way when needed to write some specifics manually, otherwise reducing the possibility of errors and security issues (that happens with more junior developers whether we want it or not). Hi Adin, let me comment back 1) same scenario happens, there39s a limitid amount of threads serving limited amount of clients. 2/3) Referenced presentation shows some measurements and numbers, you may be quite right on the internals but the common rough overview still stands as a general comparison of how things work between those two worlds. 4) parallelization options are also discussed within the article - as background worker processes, or several node processes behind a reverse proxy, or with Node clustering API (which is still in Experimental, but will be there eventually). Thanks for the great comments and the quality feedback on the article with that additional info, I appreciate it. Yes, you can have multiple worker processes, even communicating through Message Queue (MQ). Those workers can be separate Node processes (as node is single-threaded, unless you experiment with clustering API - I haven39t tried yet as the API is very early and probably immmature), but can be any other language. I39ve worked on such a system which ran C on Mono for background processing in a distributed CQRS architecture. Any calculation that keeps the CPU busy until the calculation is finished. Imagine some operation that requires 2 seconds to perform the calculation. Hit that with 100 clients - you get a 200-sec delay. Note the article I have referenced, which explains the blocking of the event loop: zef. me/4561/node-js-and-the-case-of-the-blocked-event-loop Yes, that falls under the idea of having 39backend worker processes39 in a distributed system. As the system is distributed, those workers can use any language/platform, including Node. Gracias por sus comentarios. I agree on that completely, for worker processes you could use JS when it fits, and that implies Node. js as that39s what runs JS on the server, but you can also use other languages that do the particular work at hand fast. For ORMs in general, I just see them as a tool that can get something done quick for a newbie, but end up really gumming up the works later on. The closest thing I use for an ORM is a PDO wrapper (which I borrowed and rewrote from an old co-worker), that helps with writing PDO statements. github/ellisgl/GeekLab-XPDO Apologies for the wall of text. Excellent discussion 1) Agreed. But threads and processes are powerful tools. That39s why a hybrid of threads/processes and event systems typically does best in the real world. Like the much beloved nginx :) 2/3) Sorry, I may not have been clear. When I said FUD regarding threads and processes, I meant the referenced presentation. It39s just a bunch of specifically tailored microbenchmarks designed to prove a certain point. (Which is fair, given that it39s a lightning fair and can be a bit polemic. In fact, it39s a great talk. But these synthetic micro-benchmarks are not the basis for a fair and through comparison.) To say the difference between nginx and apache benchmarks is purely because of context switching is an extreme oversimplification. Nginx is specifically designed to serve HTTP requests really, really quickly in common circumstances (IMO generally by a tight coupling with the latest OS event systems, etc.). You could specifically measure the overhead of context switching, and I would wager it39s trivial. 4) But then aren39t you at the mercy of the horrible quotprocess overheadquot the referenced presentation talks about -- can39t have it both ways :) (To be clear, my position using threads/processes or whatever is not in and of itself a problem. There are way more important design factors there, the OS overhead of those entities is pretty trivial. Hence I hate it when people adopt a silly design based on the idea thread-are-bad or processes-are-bad or some other such nonesense). Everything always needs to be put in the right context. I have presented possible situations, to analyze each one deeply I39d need a book :-) Still, I really appreciate your comments and insights, they are valuable addition to the article. Thank you for those. When use node. js as api server, and the back-end db is the bottleneck, if the clients are the other applications, not user interface, can we just let these client requests hang there waiting for db operation complete(sine node. js can handle massive concurrent connections easily) Is a MQ necessary in this scenario In my opinion, node. js is right the queue. ORM does not exist to make query languages quoteasierquot, it39s a tool used to encapsulate database concerns, isolating them from the application. There are several benefits, but ultimately, it makes applications easier to test and maintain years down the road. Excuse the tangent, nothing to do with node. Yes, you could, but Ruby would be a poor choice if your aim is performance. ) thank you for a great article. By using the node. js child process nodejs. org/api/childprocess - would you be able to overcome the high computational blocking Fibonacci issue any real life examples What of the Facebook example you used. When a user clicks on the like button there is an immediate acknowledgement but the data is written later. Cant that be an example of node used with relational db Anyway what makes up the message queue Maybe go-lang is alternative choice. ) This article is great, except for the part where it says don39t use NodeJS for computation because it doesn39t have threads. Since when do we need threads Run child processes. The only advantage to running threads over child processes is shared memory. Last time I checked, any system large enough for this entire debate to be relevant anyway is going to span multiple servers anyway, their by nullifying any benefit of threads. So, get it out of your head that NodeJS can39t do CPU intensive work. And, if you can39t, contact HildoerSystems, and we can fix all the stuff you built wrong with NodeJS. One application that few people use, but could be really fanastic, is using NodeJS to build a desktop application. There39s plenty of packages out there - personally, I favour Node-Webkit github/rogerwang/node-webkit. Hi, nice article. However I would like to point one thing, NodeJS is not running in a single thread. The programmer doesn39t have to spawn new threads, they are handled by node itself on event basis. NodeJS is evented, each function call per event will run in a separate thread. That approach encourages writing lighter functions. If your function does a lot of computation, reactor it into smaller ones and they all will run in separate threads. Think about the example where you process file while streaming. That is possible thanks to threads. Great article BTW, what software did you use to make the images/wireframes This is very well written. Thank you for this gt The technique used to avoid exceptions bubbling up to the surface is passing errors back to the caller as callback parameters Excuse me, but that seems misled. In my understanding, Node-style callbacks(nodeguide/stylecallbacks) (i. e. the pattern of passing errors as the first param to callbacks) are a side-effect of the event queue (returning control as soon as possible to allow for concurrency) itself rather than a design to avoid interrupting flow. The fact that exceptions do not bubble are actually quite often a source of errors, especially to newcomers. Great Article. Wondering who made the beautiful diagrams :) Great article, thanks :) BTW, which tool do you use to draw the images For those that are curious, it seems the images were created with Adobe Photoshop CC. I checked this by looking at the EXIF data of one of the images: exifdata/ File Size 61 kB File Type PNG MIME Type image/png Image Width 624 Image Height 600 X Resolution 72 Y Resolution 72 Color Space sRGB Color Mode 3 Compression Deflate/Inflate Orientation Horizontal (normal) XMP Toolkit Adobe XMP Core 5.5-c014 79.151481, 2013/03/13-12:09:15 Creator Tool Adobe Photoshop CC (Macintosh) Also, the fact that javascript is not able to check type compliance introduces dificulty in expontaneous organization of huge number of coders updating the same codebase simultaneously. Mmmm disagree, if you use correctly a good ORM (take a look at Mature ORMs) you get also a distributed cache of your Relational Database that allows you more performance for the same bucks and more scalability of your sistem. ORM is not just for easing the life to newies. It is non sense to use a non-blockin sistem such as node. js, if at the end you get blocked at your Database. But using a ORM that way, is not for newbies. Glad you mention, most people don39t mention this. I39d rather keep Node decoupled from the browser and keep the flexibility of running the frontend on platforms that normally don39t run Node like smartphones. For that matter, since you can do an async shell to a console application, you could easily write your worker in, for instance golang, and then use a generic pool to limit your cpu workers. from there, you can shell out to a more efficient worker. You can also do that for CPU intensive JS as well, I did this for my scrypt-js module (there are binary modules that are more performant, but I wanted one without compiled dependencies). It39s not that hard to queue work to other systems, and no reason node can39t be used to orchestrate said work. Could could use an intermediate system such as TypeScript, you can also use a linter (jshint) and even require a level of test coverage in order for release. Getting 100 test coverage is generally very easy in scripted environments. Would suggest looking into Mocha, Chai, and Proxyquire. If you aren39t writing unit tests, type safety really doesn39t give you much. I am beginning to find Node. js quite interesting. However, the paradigm it appears to be promoting is hardly new to IT. In the mainframe communications world we called such capabilities, quotre-entrantquot, where a single process could handle a high level of calls to it. Microsoft implemented similar capabilities with its Singleton object infrastructure and I imagine the Java world has done similar implementations. Oddly enough, the Microsoft recommendation for enhancing scalability across the wires to back-end services was to promote the quotSingle Callquot object structure or one object instance per calling request. Thus, the argument made for Node. js is actually contrary to the Microsoft recommendation BTW, a recommendation I never quite understood. In any event, as a business ASP developer, I am not sure if I would find any use for a Node. js implementation, though our web designer may. On another note, I would like to add my own opinion on the use of ORMs. ORMs are great tools when faced with an existing database structure against the requirements of a new application as the ORM can handle a lot of the mundane, repetitive coding that is usually found with any database application. However, because ORMs are high-level layers, they are usually not the most efficient options to use against databases whereas direct access through native providers are. In many respects, better to do the repetitive coding for efficiency over applying a heavy-weight interim layer such as an ORM. Very interesting observation. I39d like someone to elaborate a bit more on that. I would like a more concrete example, like some piece of concrete code calling an async heavy-computational function, and someone explaining what happens if that is run in a multicore equipment. Does the thread that was sercing http requests gets blocked Or another thread is used for that Node is terrible as a web server. Even the creator suggests that this is not what Node is intended for, and that it should be leveraged for it39s strengths. JavaScript quotEverythingquot, just like worker processes, is ludicrous. This is ridiculous. Node was built with the web as first class, and it excels as a web server. It is rapidly replacing Ruby and PHP in many enterprise organizations because it has demonstrably boosted both application performance (reduced page-load times, etc. ) and developer productivity. You can in fact create multi-threaded servers using Node. js to offer more stable performance but it does take a lot of extra work (see the built-in cluster module and the childprocess module). I have created a framework which runs on multiple CPU cores and solves much of the issues discussed in this post. Check it out: nombo. io/ Connor James Leech does something like mongoose. js solve the node relational database issue mongoosejs/ Yes - see the queue/pre-forked worker pool approach adopted by EWD. js: gradvs1.mgateway/download/EWDjs. pdf Summarised here: gradvs1.mgateway/download/EWDjsMechanics. pdf yeah, I was wondering about it too. great visual awesome post. Erick Ruiz de Chavez Just to complement what Tracker1:disqus said on his comment, JavaScript is usually criticized about the type checking (and many other misunderstood features, like quotthisquot), but the truth is that JavaScript is just very different to what most of the developers are used to do, and most of the developers who sadly have bad comments about it are just those who haven39t had the interest or the time to understand how it really works. JavaScript development is not only about the language itself but also about the tools you use to work with it, to mention some more you should really take a look at Grunt, Uglify, Yeoman, CoffeScript, etc. Erick Ruiz de Chavez I might as well make myself a giant noob, but to put a quick example, any disk I/O operation is considered a blocking operation as it has to perform a physical operation to read some data from the disk. Another blocking operation example is querying a DB, where you basically have to wait for the response before doing anything else. I39d say, any sort of computational operation will be as blocking as the time it takes to complete. In any of the above examples, you usually have your blocking request on line A and line B wont be executed until line A is completed. Node. js instead is asynchronous, so line A is requested and then queued, and line B is executed no matter if line A is completed or not when line A is complete, you are notified either with a callback or with an event and then you can continue doing whatever you need to do with such result. Very helpful article npm install felixge/node-mysql. That might be the most useful repository I39ve seen in ages. Erick Ruiz de Chavez I have a small example of mysql and node. js at github/erickrdch/node-mysql-demo How about: quotWhy the hell would I read an article without an obvious date and time stampquot Nice article, indeed. But, hfuti:disqus, you39re wrong in saying quotNodeJS is not running in a single thread. each function call per event will run in a separate thread. quot As far as I understood, the main NodeJS event loop consuming your JS code in fact runs in a single thread. All potentially blocking and/or long-running tasks like disk I/O is delegated to and executed by libuv as part of the node runtime engine which spawns a limited number of threads made available as thread pool. Said this, it39s obvious that the main event loop thread is not affected or blocked by other (yet again asynchronous) code execution. So, for example, file I/O with the fs module itself is implemented in a non-blocking manner - in the end as good as the OS/kernel allows non-blocking operations. Of course foreign processes or threads could always be spawned by custom modules or 3rd party services (worker processes). And yes, there are runtime env projects handling more than one node process and their threads on the same machine or cpu cluster. But that39s another story. Feel free to correct me if I39m wrong This is fantastic. Very well written article. You put a lot of thought into it. Quick node/express question I am I am adding rapid data entry, not batch, data entry to my system I have a form (mfntapes) that works great. I have a test form (joe) the prompts for the number of times I want to call the mfntapes form The gist contains the code, fails to work, the after prompting for cnt attempts to call for mfntapes cnt times. The question is how to call form mfntapes x number of times where x is a vairable See lines 45-55 of gist. github/toulon/9571625 ORM for real projects are useless hone. Nice article :-) gt SERVER-SIDE WEB APPLICATION W/ A RELATIONAL DB BEHIND I wonder why Node is not good for that You have promise based SQL libraries (like Knex) which enables non-blocking queries. Node has no opposition with relational databases: it has no interest with blocking I/O drivers only. Relational or not relational. I wish NodeJS was not (almost) systematicallty presented as THE de facto alternative to the traditional threaded webserver. Async IO is not exclusive to NodeJS Most major languages out there - including Java and PHP - have async IO frameworks similar to NodeJS. This wiki page lists most of them: en. wikipedia. org/wiki/Reactorpattern I39m not saying NodeJS doesn39t have its merit, but I39m sick and tired of seeing people flocking to it as if it39s the only async IO stack available, and the only alternative to the good ol39 PHP or Rails stack. To be honest, we may be stuck with Javascript on the browser, and will be for a very long time (except if Javascript becomes just another target platform/language thanks to asm. js), but I can39t come up with any good reason to use it on the server side in favor to other available languages. Most of the alternatives are just way better as a language, have better standard libraries, tools and resources. Please stop spreading Javascript on the server, it39s creepy :p Jarle Leopold Moe How would you upload files What about Directory integration (Active Directory, Open Directory) What about communication with external services All request depending on a response from any of these types of services would block the calls. Node. js is single-threaded it39s only applicable for certain types of tasks. These re great examples of why Node is so much better than the competition at web services. None of thee are blocking operations in Node. They39re asynchronous. While other servers waste resources spinning off separate threads, Node fires off an event-driven asynchronous operation and keeps taking more requests in the meantime. The practical upshot is that porting web services from PHP or Ruby can deliver between 2x and 10x improvements in simultaneous connections and typically 30 - 60 improvements in average response times. Lots of big companies are doing web Node projects just for these reasons, including Adobe, Paypal, eBay, Walmart, Yahoo. Groupon, Under, etc. very nice article and very clear thought regarding node. js where to use and where not Every major application development platform has already had support for HTML5 for the past several years, including websockets for bi-directional communication. Add to this the strong types, multi-threading and the tons of other stuff that languages such as Java have to offer and I seriously question why anyone would waste their time using this. Just want to mention that node is not the only server side option for javascript especially since oracle put the nashorn javascript engine on the jdk. Now you can also use all the jvm goodness from javascript we are using vert. x as the async server and nashorn to use javascript. You can see some code samples in this module github/core9/module-nashorn the project site is core9.io. This is an amazing overview. Thank you Very well written. Gracias por compartir. I39m with you. For trivial application an ORM is fine. You have to remember that most devs really only have experience with trivial applications. So they will argue for an ORM because they can39t learn SQL or don39t have the time or staff to right stored procs. And they have never heard of Memcached and so think the ORM is a cache. lo que sea. And the weirdest excuse I hear is about decoupling. The ORMs I have had the misfortune of running across do the opposite. They very much tightly couple the UI to the database. ORM layers are large and buggy. So how do you test it Yeah, good luck unit testing it (which you have to do because they are buggy). If you are integrating with AD then you are probably in a Microsoft shop. And if you are uploading files to a web server then your environment isn39t very sophisticated. So for you, you probably should just stick with IIS and VB. Microsoft public recommendations for architecture are a joke. Microsoft is a marketing and licensing company. They are not a tech company primarily If you have a quothuge number of coders updating the same codebase simultaneouslyquot you have larger problems. Dev teams don39t scale well. I would run. With too many cooks in the kitchen the broth will spoil. There is going to be no accountability and no responsibility with that many people contributing. Why Node is different - using bar as analogy bahmutov. calepin. co/why-node-is-different lta hrefquotwww. amjad-almadinah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D8B4D982D982-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotwww. amjad-almadinah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D981D984D984-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotwww. amjad-almadinah. org/D8AED8AFD985D8A7D8AA-D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/D985D983D8A7D981D8ADD8A9-D8ADD8B4D8B1D8A7D8AA-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotwww. nsmat-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D8B4D982D982-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotwww. 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org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/D8B4D8B1D983D8A9-D983D8B4D981-D8AAD8B3D8B1D8A8D8A7D8AA-D8A7D984D985D98AD8A7D987-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988/quotgt lt/agt lta hrefquotwww. hamd-dammam. org/D986D982D984-D988D8AAD8AED8B2D98AD986-D8A7D984D8A7D8ABD8A7D8AB/D8B4D8B1D983D8A9-D986D982D984-D8A7D8ABD8A7D8AB-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotwww. hamd-dammam. org/D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/quotgt lt/agt lta hrefquotwww. hamd-dammam. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D985D986D8A7D8B2D984-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt lta hrefquotwww. kema-dammam. org/D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/D8B4D8B1D983D8A9-D985D983D8A7D981D8ADD8A9-D8ADD8B4D8B1D8A7D8AA-D8A8D8A7D984D8AFD985D8A7D985/quotgt lt/agt 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forsan-almadinah/D8AED8AFD985D8A7D8AA-D8B9D8B2D984-D988D8AAD986D8B8D98AD981-D8A7D984D8AED8B2D8A7D986D8A7D8AA/D8BAD8B3D98AD984-D8AED8B2D8A7D986D8A7D8AA-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotwww. forsan-almadinah/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D983D8B4D981-D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/D8B4D8B1D983D8A9-D983D8B4D981-D8AAD8B3D8B1D8A8D8A7D8AA-D8A7D984D985D98AD8A7D987-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988/quotgt lt/agt lta hrefquotwww. forsan-almadinah/D8AED8AFD985D8A7D8AA-D985D983D8A7D981D8ADD8A9-D8A7D984D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D8A7D984D985D8A8D98AD8AFD8A7D8AA/D985D983D8A7D981D8ADD8A9-D8ADD8B4D8B1D8A7D8AA-D8A8D8A7D984D985D8AFD98AD986D8A9-D8A7D984D985D986D988D8B1D8A9/quotgt lt/agt lta hrefquotwww. amjad-jeddah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D985D8B3D8A7D8A8D8AD-D8A8D8ACD8AFD8A9/quotgt lt/agt lta hrefquotwww. amjad-jeddah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D981D984D984-D8A8D8ACD8AFD8A9/quotgt lt/agt lta hrefquotwww. nsmat-jeddah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD8B3D984D98AD983-D988D8A7D984D8AAD8B3D8B1D8A8D8A7D8AA/D983D8B4D981-D8AAD8B3D8B1D8A8D8A7D8AA-D8A7D984D985D98AD8A7D8A9-D8A8D8ACD8AFD8A9/quotgt lt/agt lta hrefquotwww. nsmat-jeddah. org/D8AED8AFD985D8A7D8AA-D8A7D984D8AAD986D8B8D98AD981/D8B4D8B1D983D8A9-D8AAD986D8B8D98AD981-D8A8D8ACD8AFD8A9/quotgt lt/agt lta hrefquotwww. nile7/D8B4D8B1D983D8A9-D985D983D8A7D981D8ADD8A9-D8ADD8B4D8B1D8A7D8AA-D988D8B1D8B4-D985D8A8D98AD8AFD8A7D8AA-D8A8D8A7D984D982D8B7D98AD981quotgt lt/agt lta hrefquotwww. nile7/D8B4D8B1D983D8A9-D8AAD8AED8B2D98AD986-D8A3D8ABD8A7D8AB-D8A8D8A7D984D8ACD8A8D98AD984quotgt lt/agt lta hrefquotwww. nile7/D8B4D8B1D983D8A9-D8B9D8B2D984-D8A3D8B3D8B7D8AD-D8A8D8A7D984D8AFD985D8A7D985quotgt lt/agt lta hrefquotstorify/monyhusseinquotgtlt/agt lta hrefquotmonyhussein. deviantart/quotgtherelt/agt lta hrefquotfreee4des. blogspot/quotgtherelt/agt lta hrefquotemyhusssein. tumblr/quotgtlt/agt lta hrefquotkenanaonline/users/monyhussein/quotgtlt/agt Just to let you know you have quotsupport supportquot in How it works under-the-hood is pretty interesting. Compared to traditional web-serving techniques where each connection (request) spawns a new thread, taking up system RAM and eventually maxing-out at the amount of RAM available, Node. js operates on a single-thread, using non-blocking I/O calls, allowing it to support support tens of thousands of concurrent connections (held in the event loop). Isn39t it possible to get the date of posting of your article or all your posts for that matter. It is really disturbing to read technical posts without dates. thanks You mention Node. js is good for a chat application because it39s not CPU intensive. I can39t think of too many use cases that don39t require much CPU. For example, could Twitter be built with Node It seems there39s a lot of computation required just to generate your feed. Node. js uses certainly can39t be so narrow. Great article. Gracias. There39s an old joke: you39re not a paranoid if they39re really out to get you. That39s the attitude that should be taken when it comes to Web application security. One thing that bothers me about Node. js is that I have no insight into how secure it is. When an environment like Grails, where I have Java/Groovy running on Tomcat I have some confidence in Tomcat security, if for no other reason than the fact that Tomcat has been around a long time and has evolved. This isn39t true with Node. js. I was also looking at the Node. js libraries. At least for the file access, it appears to be nothing more than a thin layer over the POSIX file system calls. I like the Java or even the C file abstractions more. The main argument that I see for Node. js (made in this post) is that it has really lightweight threads and that you can have JavaScrip everywhere. This last issue is an attraction for those who only know JavaScript. As far as the light weight threads, this is not so much a language issue as a platform support issue. It should be possible to support this kind of thread model in another language. Toptal designer did the design for them. your comment is ridiculous too, ORM is not a everyone39s accepted pattern. The irony is that lambda39s (aka, anonymous methods) are the basis of both javascript and the preferred technique for C39s multiple implementation of the same callback pattern, albeit with full type safety. In fact node39s major characteristics (2-way, lightweight, asynchronous has effectively been implemented in C as quotSignalRquot, and there are several language features which are both asynchronous and natively multithreaded, (unlike node. js). Now I could understand if your experience with ORM39s was limited to Hibernate (absolutely awful, one of the worst implementations of a major concept I39ve ever had the displeasure to work with) or even EF, which at least is fairly powerful and expressive due to LINQ, if data nanny overkill. But a micro-ORM like Dapper gives you all the flexibility and power of direct SQL with the benefits of rich data manipulation via objects, and is fast, very fast. And I39m sorry, but OOP is a well proven, very effective design strategy if you know what you are doing, i. e. you are a pro. I see three major problems with the node. js approach that no one seems to have a good answer for: So you start with the premise that there are such inefficiencies in waiting for IO that there is a huge potential there. So yeah, you39ve got great concurrency, right until you get to the first blocking library, a database, a file server, etc, which is practically every major piece of functionality written. So it39s just hurry up and wait for 10,000 connections instead of 100, ok that39s something, but where does it get you So then you start rewriting all those services asynchronously, but that39s just a snake eating its own tail, because that39s hurry up and wait too: Because in the end every database on earth ultimately comes to a magnetic arm skipping across a disk or reading solid state memory, and that39s assuming you39re on the same machine, as opposed to distributing data across a pool of far slower network connections. Then you have the single threaded issue: There is probably no more misused language than Javascript because the barriers of entry are so low. And while early adopters might understand a bad practice when they see one, most javascript programmers simply have no idea what they are doing. Thirdly, Javascript is not exactly a particularly fast language, so the advice seems to be don39t do compute intensive tasks. Where does that get you So you end up with an elegant solution to one category of issues, but you39re trapped there, with no way out of the non-compute intensive, hurry up and wait ghetto. Wow, that is one seriously ignorant statement. Uploading files to webservers is THE stated rational of node. js39s inventor for why he wanted a non-blocking library. So when you fanboi39s break out of the single threaded, slow dynamic world of cut and paste code with zero type safety, multithreading, and only one trick pony (lambdas) to match 39s multiple asynchronous capablities, (all so that you can get 10x more users to hurry up and wait for IO), then you can lecture us about quotsophisticationquot. The framework has a vastly more advanced feature set than any language you can name, period, and IIS, properly configured, can beat the piss out of Apache and can readily match nginx as a reverse proxy or for static content. In the end you39ve got several problems which are intractable: 1. Javascript is slow, and your technology of choice is single-threaded, so intensive compute tasks are off the table. 2. Javascript debugging and testing blows in comparison with any typed language. Pro39s use extensive testing, not fly by the pants 39hey it works39. 3. The 39everything is modular39 approach is not an architecture, it39s an invitation to chaos, like Perl or PHP. 4. Concurrency doesn39t buy you crap if all you are doing is waiting for some other IO bound process, which is pretty much everything worth doing with computers. 5. The quality and experience of many javascript programmers (not node. js programmers necessarily, but it39s popularity will bring them) is remarkably poor, as demonstrated by comments in which fanboi39s prove that they have no idea how other systems that actually don39t ignore any computing problem they can39t solve work. ORM is just a work around for the problem of impedance mismatch, nothing else. Its not big deal, about OO its a cross paradigm like AOP and its not really based in nothing else beyond encapsulation. Without procedural paradigm OO does nothing, every real skilled programmer already knows that. Impedance mismatch involves all sorts of ramifications, especially in regards to maintainability, portability, extensibility and performance. To quote Ethan above (since my explanation obviously didn39t take): quot. it39s a tool used to encapsulate database concerns, isolating them from the application. There are several benefits, but ultimately, it makes applications easier to test and maintain years down the road. quot quotabout OO its a cross paradigm like AOP and its not really based in nothing else beyond encapsulation. Without procedural paradigm OO does nothingquot Ok, I39ll be sure to spread the word that we should stop fooling around with all this esoteric OOP stuff and get back to a language that lets us do everything vis-a-vis encapsulation: VB6. You39d think a Javascript programmer might want to mention inheritance, if not polymorphism, since javascript has a relatively unusual mechanism for it: prototypes. A singleton is an instantiable (non-static) object with a private constructor so that only a single instance can be created. (Imagine an instance class with a static property exposing an instance of itself that depends upon a private instance constructor). It was actually implemented in Java before existed. Perhaps what you are thinking of is a non-blocking Callback mechanism, which is handled in C via delegates, events (multicast delegates) and the new async and await keywords that transform standard C into a lambda to be executed at compile time. It also handles multi-threaded asynchronous operations via it39s Parallel extensions, which permit spreading load across multiple threads/cores as long as that work is not serial in nature. Also, I would encourage you to check out a micro-ORM like Dapper. It39s far less comprehensive than EF, but it39s far more flexible and gets out of the way, plus it39s significantly more efficient than Hibernate and EF (about 5x faster for reads) Yes this article rocked tits. Esp good for a Croat with ESL ) nodeboy So after reading your article I still havent figured out why Node js want to reinvent the wheel. I still think node js and the likes are crap. A great introduction to find out what it is JavaScript and once the answer to from lta hrefquotgoo. gl/cfkytpquotgtbagaimana tips mengatasi wanita frigidlt/agt Noob questions: Um, isn39t the ease with which you can move request data (i. e. untrusted data) into database (where data is assumed to be trusted) a big hazard How do you ensure that you never forget to inspect every piece of incoming data when it arrives, before you start trusting it Generally, I would assume something as popular as Node. js would have thought of this, but I remember back when Rails had blanket model update. That changed real quick when Github39s use of this quotfeaturequot was exploited (fortunately, by a whitehat). Also, of course, just because you add a conversion speed bump does not mean that people won39t make mistakes, but at least they39re more likely to give it some thought, which probably means they39re going to make less mistakes. I don39t understand the angst against using an ORM. Were you in a proper environment where concerns were separated The ones bashing ORM just sound like they don39t know what they39re doing or how to engineer proper software. Why on earth would I want to go from writing software in Java/C/whatever to drop into SQL where it is hard to version, properly test, and can apparently cause severe brain damage Everything is a double edged sword - an implementation or a convention like using an ORM over raw SQL really doesn39t matter. Depending on the situation raw SQL might be best. it might be better to use a NoSQL store. maybe an ORM is fine Usually, from my experience, I can tell you that an ORM is better for a lot of reasons, and they have been relayed by M. I spent the time to write my own libraries to abstract vendor specific implementations and you need to create your own mappings. You can easily spawn from a certain state or use existing data structures. It took time to write my libraries and it was not easy at all to do it but it was well worth my time to do it since I can now reuse my libraries. Is it the BEST I don39t know. I like it but I certainly won39t go around to arbitrary technical articles that have nothing to do about SQL and post something like quotYes this technology is good but stay away from raw SQLquot I just don39t see a need to be bashing anything here, especially an ORM when the article is exclusively about JS and NodeJS. Probably one of the main points of this article, that gives Node is supposed scalability, is the offloading to a Queue or Service Bus that leads to asynchronous processing. That is a well proven architectural pattern, available in many languages, is especially used in CQRS (Command Query Responsibility Segregation) with Event Sourcing, is very well suited to be used by technologies such Reactive Extensions that provide considerably greater functionality and flexibility than Node. Asynchronous programming and handling its pitfalls has been around without Node for years, if you had knowledge of enterprise development. As for the hate against ORMs. you guys crticising it seem to be moving from front-end development into an area where you have no knowledge or expertise in OO, BDD, TDD or any other proven Enterprise level methodology. No concept of integration other than Twitter feeds. No experience of complex Workflow or scalable caching. This is one of the dangers - you know JavaScript, and a bit of SQL. So everything else is superfluous - until you need it, such as the attempts to bring an element of type checking to JavaScript. Seriously, each technology has its place, but there is no one size fits all approach. Appreciate the strengths of each technology, and use them where appropriate. Great introduction to node. js Thanks, i samo naprjed Because they suck for a complex application. Sure if your scenario where you spent all this time trying to make the ORM work the way you need it to, you could have just put that same effort into writing the SQL properly and making sure it39s organized etc and you would be further along in the project and have more control over the application. ORM39s are great at saving time on a small to medium scale project, but once you delve into more complex and larger applications, you39re going to spend either A.) A lot of time coding to make the ORM work the way you need it or B.) Just decide to write the SQL yourself because the time it takes to make the tool work how you need it just isn39t worth it. Very great post you add JavaScript is better than some of the other programming languages. therefore lta hrefquotgoo. gl/L7tXeOquotgtcara menghilangkan gatal keputihanlt/agt better fit with JavaScript Great, informative article. Gracias por compartir esto. lta hrefquotwww. unlockpwd/quotgtUnlockpwdlt/agt Its very good post thanks Pot, meet kettle. Those may be intractable problems if any of them were true. None of them are: 1. a) JavaScript is all JIT these days and delivers 1-2x native code performance (faster than any other dynamic language I39m aware of). b) Non-blocking by default can deliver orders-of-magnitude improvements in code efficiency - transparently. 2. Almost all modern editors support type inference for JS. ESLint, Closure Compiler, and a number of other options offer sophisticated static analysis capabilities. TypeScript even offers a nice structural type system. 3. The opposite of modular is a tightly coupled monolith. That39s a bad idea in ANY language. 4. quotif all you are doing is waiting for some other IO bound processquot - Non-blocking by default means you39re NEVER waiting for some other IO bound process. That39s why Node delivers such huge improvements on resource utilization. 5. 2006 called. They want their language-snob attitude back. The days when serious engineers considered JS to be a toy are long since over. JS powers sophisticated enterprise applications at just about every fortune 500 today. Additional point: JS is the only language with fully native support for isomorphic code (meaning you reuse most of your application on both servers and clients). You can write JS ONCE, and it will power the server, the web browser, and mobile devices including iOS and Android. See React Native. leanpub/learn-javascript-react-nodejs-es6/ 1) 1-2x native code performance Do the electrons run faster on node code Not a good start. 2) Type inference is mapping variable declarations to types without explicit syntax, i. e. a) it requires actual types, and b) compilers enforce type safety, not editors. And you can dress it up any way you want, but there is no way to enforce sophisticated state analysis with slop-tastic dictionaries of whatever stored in strings amp functional delegates. Also, Typescript is not Javascript, it is Javascript with a half-assed type system pasted on top. Even Google is abandoning Js for Typescript in Angular 2.0 Why Because Google has decided that an untyped system is insufficient for serious work. But is that type system anywhere near as sophisticated as a compiled language Nope, not even close. 3) You are misunderstanding what I was characterizing as quotmodular designquot. The alternative is not monolithic code, but encapsulation, specialization via inheritance (or prototyping), polymorphism, and externalizing dependencies via IoC. The alternative is SOLID, i. e. modern Object Orientation. 4) Your process may not be waiting, but your customers are waiting for the callback. My point is that being able to serve more requests doesn39t do you any good if every served request then has to wait on yet another operation. In the end, somewhere somehow, you will eventually be going to a disk or waiting for IO, because that39s where the information the customer wants lives. 5) I didn39t say that JavaScript was a toy language, I said that most JavaScript developers are well-meaning, cut and paste amateurs, and they will invade the ranks of node. js developers as it becomes more popular. I39ll take a strong type system over quotfull native supportquot (that39s not native) for quotisometricquot code that can run on clients or servers you say that like that39s a good thing any day. Wow, Js on android and iOS I guess the days of Apple adding another strongly typed, native language for iOS are overlt/sarcgt Obviously you39ve never heard of Mono, the cross platform that compiles and runs on every major OS, produces native runtimes for all three major mobile platforms, and runs on everything from beowulf clusters to wearable devices. This is why we don39t respect you. You don39t know or understand anything that came before, or anything outside of your javascript bubble. You don39t solve any problems that weren39t solved before, but yet you39re convinced you have all the answers. That seems to be a common theme with anyone whose education system stressed self-esteem over critical thinking. This reply just strikes me as willful ignorance. 1. Really Rather than investigate and learn the truth, you just want to ridicule the answer I39m not taking the bait. Watch Brendan Eich39s Fluent talks if you39re interested in actually learning something. 2. I know what types and type inference are, and I know the benefits of static types. I39ve been in this game since before JavaScript was invented. TypeScript is a superset of JavaScript that compiles to JS amp allows for sophisticated static analysis. It39s structural type system is better than the type system Java had back when I was coding in Java, and it39s much better (as in more reliable and flexible) than C and C. 3. quotencapsulation, specialization via inheritance (or prototyping), polymorphism, and externalizing dependencies via IoCquot - these are all forms of modularity, and JavaScript modules provide viable alternatives to all of them - and in the case of class inheritance, it39s far superior. See medium/javascript-scene/the-two-pillars-of-javascript-ee6f3281e7f3 4. quotyour customers are waiting for the callback. quot Fortunately, that39s where the performance I talked about in point 1 shines. JS provides efficient utilization of I/O resources. In fact, dealing with I/O bottlenecks is the entire reason that Node was invented. I39ve ported several large production projects from PHP and Ruby to Node, and seen dramatic reductions in response times, both average response times and response time ranges - and since a typical Node app utilizes a small fraction of the memory required for C applications, your customer I/O competes less with the RAM paging you might experience with a compiled C application. 5. quotyou say that like that39s a good thingquot I39ve seen objectively measurable increases in team velocity ranging from 40 - 60 improvements. Believe it or not, it39s a fact, and being more able to adapt to changing needs and experiment more (particularly in the UI layer) delivers very real business value. Why do you think so many enterprise organizations are adopting Node It39s not because some dev prefers JS. It39s because they ran the tests themselves and figured out it39s a huge win. quotObviously you39ve never heard of Mono, the cross platform that compiles and runs on every major OSquot Yeah, I have - what I haven39t heard of is Mono delivering anywhere near the value that Node delivers in enterprise production. Got a good article on that 39Cause a quick Google search isn39t turning up much. Check out this awesome result in the top 3 of the SERP: www. quora/Why-isnt-C-with-Mono-popular-for-enterprise-applications-on-Linux-servers. but a quick Google search for Enterprise Node. js delivers quite a bit. Here are the top 3 search results I see: blog. risingstack/node-js-is-enterprise-ready/ www. joyent/nodejs-support www. centurylinkcloud/blog/post/node-js-is-taking-over-the-enterprise-whether-you-like-it-or-not/ There39s really no contest here. 1, yes, I39m mocking your evidently accidental claim that JavaScript makes electrons run faster, or even as fast as native, because it39s patent nonsense. Not only is that impossible, it ignores one of node. js39 acknowledged weaknesses: It sucks on compute intensive operations, because it39s single threaded, which means compute intensive operations block execution. duh 2. Your knowledge of Java does not qualify you to understand what a competent type system is. Java39s generics are a largely useless, johnny come lately me-too feature when compared against to C generics because they suffer from run-time erasure, in other words, the generic type safety and reflection only works at compile time, because at run time, everything is cast to an object. So when you are going on about static analysis, you are effectively trying to claim it39s as good as compile time run time type reflection, which is very far from the truth. 3. Meh. Chopping up everything into discrete functions is a form of modularity too, but it39s vastly inferior to SOLID, which was my point in the first place. And while prototype based inheritance is interesting, it39s hardly better than real inheritance, which permits far more flexible arrangements. 4. I don39t see how it39s impressive to speed up a Ruby app, or refactor some craptastic PHP into something faster. Your memory overhead claims are equally baseless: I can run micro on a watch or on an arduino device. I can write that runs very well on an under-powered phone. Look at the memory chrome consumes for an SPA, or try to run a complex javascript app on a tablet, and then tell me how quotlightweightquot JavaScript is. 5. The lack of a proper separation of concerns (which is the cause of most maintainability problems) is the number one issue I encounter at enterprise scaled customers, and an impressive team velocity is always how they got there. Why do I think a number of organizations are choosing node Because typically a mediocre, over-sized team of moderate competence f39d up the previously shiny new thing that was supposed to solve all their problems, so they want to believe the hype that the problem is not them, but their previous technology choices. 1. I think you misunderstood my meaning. JS runs 1-2x SLOWER than native -- much better perf than any other dynamic language I know of. It39s fast enough to run AAA game engines like Unreal Engine and Unity in stunning quality at 60 fps. 2. I actually think that a good native type tool would be a good addition to JavaScript, but only if they39re user-definable structural types. That said, JavaScript does support static analysis via type inference, and there are a number of ways to provide type hints for dev tools. In addition, JavaScript also has an impressive array of runtime analysis tools. 3. quothardly better than real inheritance, which permits far more flexible arrangements. quot Wrong. medium/javascript-scene/the-two-pillars-of-javascript-ee6f3281e7f3 4. My apologies. I was not aware of micro. JavaScript also runs as-is on low-powered devices including Arduino, Tessel, and a number of others. Node works great on most of them. If that39s not small enough, you can create a custom Node compile, drop features, even swap out the V8 engine for a different JS engine if you need to. You can also restrict yourself to using tiny JS libraries (of which there are many on npm) to keep your codebase compact. 5. quot. they want to believe the hype that the problem is not them, but their previous technology choices. quot That might explain an experiment or two, but the Node takeover is much more than that. We39re rapidly replacing apps in a variety of languages with Node. Having worked at a fortune 500 during the transition to Node, I can tell you our justifications: We did experimental ports to Node, found: 1. that the app was faster and more reliable, delivering huge wins in both average response time, and the number of requests we could serve with the same machine, and 2. The developers were more productive for a variety of reasons, including the fact that JavaScript specialists could more easily work on both sides of the stack without context switching, and a lot of code could be shared in both the server and the client. Those advantages have real, measurable influences on the company39s bottom line. That39s why Node is taking over at both startups and enterprise companies. especially with edge it is really handy Thanks Tamisalv I was looking for quick reference read for understanding node. js and why projects might use it. Reading this gave me a better understanding of advantages of this this technology and also when one might use it. Cheers quotAfter over 20 years of stateless-web based on the stateless request-response paradigm, we finally have web applications with real-time, two-way connections. quot As a result we have webpages which take longer to load nowadays when we have Internet speeds in the order of megabytes per second, than back in the day when our speeds were in the order of bytes per second but our webpages were plain simple HTML. Nowadays we have webpages which load halfway and then stop, which crash at the slightest network error i. e. dynamic IP address reassigning, or a momentary lapse in the WiFi signal forcing you to reload the whole page, whereas browsers are designed to gracefully handle those errors or resume once the network connection is restored, buggy Javascript scripts don39t handle errors as well. I only have 1 question here with your statement. quotIt39s structural type system is better than the type system Java had back when I was coding in Java, and it39s much better (as in more reliable and flexible) than C and C. quot I can not take that. How can you examplify Some Facts (with obviously answer in no) - Why did Node inventor used V8 engine which was made in C to power node, if the js type system was so flexible and much better - Can nodejs decode vp8 codec video by itself as efficiently as C/C - Could you build nodejs on top of pure javascript instead of C - Is there any such thing as pure javascript You really have to understand my friend that it is a type system that can take advantage of underlying hardware and makes your program efficient at CPU and memory. Strongly typed C can solve any problem, even build node js. Node shines at non-blocking i/o and that is about it, it can not do anything else. Yes you can chop-off node code and make it work on micro devices but will it be efficient and make sense Can you make product like node where you have to code in C, yes you can but it would not make sense as power of C/C in not in web, its optimizations and hardware. It not like non-blocking I/O is something new, we have had that in many technologies including java. Net, basic, python and perl, this is very old. The only reason why this thing is in limelight is it has enabled millions of frontend javascript developers, who do not understand pointers and bash about C, to write server code, which is simply overwhelming, that39s why the buzz. And about quotNode in particular are actually very well suited to handle distributed computationquot, why on earth one would write such a statement Node is not made for computation. it can not compute as efficiently as C/C/Java. Período. With all due respect, lets not bring C in picture here, there is simply no practical comparison at all, or it will be very touchy. You may be interested in this: medium/javascript-scene/what-is-webassembly-the-dawn-of-a-new-era-61256ec5a8f6 Actually, Javascript in the V8 server engine is QUITE fast. The statement that Javascript is not fast is outdated. You combine Node with Chrome and you get a very fast environment. If you understand how Node works, it has an event loop that processes all code that is ready to run. So, you call a function that has a blocking database call inside and a callback when finished, it allows the the function to be called, which returns immediately allowing you to get on with other things while the database call is being processed. So you aren39t quothurry-up and waitingquot as you suppose. You get on with other things, and once the database call finishes, execution will continue to the callback which is invoked after the database call returns. So, you get the same basic abilities as a multi-threaded environment without all the extra overhead incurred by thread-state swapping. Because you don39t get quottime slicingquot you have to be careful that no piece of code takes too long to run, and if it does, you just break it up using packages like quotasyncquot. I come from a long C, C, Delphi, Java background, having mastered the multi-threaded paradigm, and I can state assuredly that the Node single-threaded async paradigm is super cool, fast, and highly scalable. IF YOU KNOW WHAT YOU39RE DOING. But that39s the same for any of the other technologies as well. None of these technologies are for neophytes. A complex application is precisely where well tailored Domain objects and properly decoupled subsystems are most necessary. If you are spending all your time trying to get the ORM to work you should either learn that ORM better or get another ORM. I would assume the former goes without saying so if you are still fighting your ORM it39s time to choose one that just works. Excepting your last comment that these technologies are not for neophytes, I think you are ignoring the last two paragraphs you were responding to. Even the founder of node. js says to avoid compute intensive operations. Yes, V8 speeds up javascript, but that doesn39t solve the problem of a compute intensive operation or IO dependent operations blocking a single thread. You then respond that node. js is non-blocking and therefore it can be awaited. Great, I got that, sure, but what are you waiting on Some code that isn39t written in node. js apparently, (so much for the claimed benefit of quotone true language to rule them allquot), because your single threaded node. js process is happily moved on to something else until the callback. So, node. js works great just as long as you can rely on other processes handling the workload that is blocking (like waiting for IO), or another instance of single threaded node. js, that will (if written quotcorrectlyquot) undoubtable kick the can down the road to yet another process. And that39s the issue: there are a limited subset of stuff done in programs that can be executed in parallel/out of order, and/or doesn39t rely on blocking operations. Multi-threading is more complicated and has some overhead every time there is a context switch, but it means that more cores can be thrown at parallelizable units of work, and even discrete operations can be handled by the different threads. In a quotnode. js solves everythingquot world, you are either relying on something not written in node. js or waiting for your single threaded node. js application to finish up all the stuff that must be done, one way or another. You know what You seem to just like spouting on about something you are clearly not qualified to speak about. You obviously have never built anything serious in Node. js. Well, I have, and I can tell you that it works great if you actually program it correctly. That means you use things like job queues, you use the clustering that Node provides, you make sure you do everything with callbacks and promises, you use quotasyncquot and quotsetImmediatequot to properly share the processor between code that is waiting and code can now execute, you make sure UI code has priority over CPU intensive code, etc. For example, I wrote an quotasyncquot heap sort algorithm that works great, sorting massive lists while not blocking for any appreciable amount of time. I also have a 5000 line heuristic algorithm that is quite complex that I split up so that the main loops are executed using async constructs. I then have these executed from a job queue called quotKuequot that allows for efficient use of all cores, no threads, great UI response time, and complex calculation jobs being executed in the background using all available processor power. This is ALL done in javascript with excellent performance in both CPU intensive tasks and response to front-end data requests. In other words mate, the UI is super responsive, and the background processing (complex heuristic calculation) performed quickly and very responsively. This is all done with a single language for both backend and front end, which is a huge deal when it comes to system architecture. Why are they not for quotneophytesquot Is it alcoholic I agree. Most times that I think an ORM is inadequate for complex queries, I write out raw SQL, later to find out the ORM has an quotapp for thatquot. I like using an ORM as much as possible, but I won39t spend too much time making it work for me, otherwise, as M said, I39ll find another ORM. Sounds like the words from a quotMichaelquot I know. ) I agree with your last statement. quoteach technology has it placequot. But why do you assume all Node developers are front-end developers with no back-end knowledge Why is it NOT possible for these developers to make a scalable solution Like or not Node is being used in Enterprise today and will continue to be adopted. Javascript is a poor choice of language for enterprise/complex development. It is messy, difficult to read, difficult to organise, doesn39t support an entire raft of OO paradigms that save a lot of code repetition and provide readable abstraction, predominantly gives run time errors, no AOP, no by convention, no reflection, no generics/templates, no precision of scope, no rich low level processing, and it is not type safe. We are stuck with it in the browser, and frankly it is only inertia and legacy support that means it is still used there. In all rights it should have gone the way of the dinosaurs 10 years ago. The main driver to move away from scripting languages was that they were a maintenance nightmare and led to ball of mud applications that had constant bugs that couldn39t be tracked. It has only been a short 10 years since we breathed a huge sigh of relief when serious development moved off of scripting languages and here we are doing it again unwilling to learn from the past, convinced that this is quotnew and cutting edgequot, rather than just old, tired and regurgitated. It will end up the same way as it did last time, being talked about with disgust like classic asp and perl cgi. I can only conclude the developers championing it now were just not around to see the fallout of this last time around. Every new generation of developer is convinced they have discovered quotthe truthquot, those of us who have seen this cycle of pain just have to sit back and shake our heads in disbelief. Unfortunately you can39t teach experience, it is something you have to learn the hard way. Sure if you are an amateur and know nothing else then by all means, but anyone trying to do a professional job needs to leave this alone and stop making populist technology choices without considering the outcomes. If you can39t evaluate the long term limitations of a technology for yourself you shouldn39t be working in development. Developers need to stop being so childish, acting like a bunch of deluded fan boys, this is a serious business, not a game. DIOS MIO. Eric. Are you for real Do you even know how Nodejs works Did you even try to look at backbone of Nodejs Just download yourself a source-code and checkout. IT IS IN PLAIN C/C. httpparcer is C lib. libuv is another and single most important C library in nodejs backbone which makes nodejs async, event driven and non blocking. Javascript by itself is body without a soul and life. JAVASCRIPT is just a script that you use to script your logic. One day if smeoene ports lua with this libs, he will not need Javascript to code. same for python etc. But the basic fact remains the same. IT IS C code that makes what nodejs is, not that javascript is too fast. in fact javascript is slowest in all of the scripting language. So don39t flatter yourself in believing that just java-script is great and other things are shit. And do not insult C/C if you have no knowledge of it. So, again, i urge you to take back your words: quotJavascript type system is better then Cquot. (Javascript has no type system. and if you still believe that it has one, you are in a very wrong field, go build some scaffolding) Also, these companies are not choosing nodejs for the reason you mentioned. This is possible in almost all languages. The reason why companies are choosing nodejs is that, they get ready made javascript coders, which are in millions and can not do c/java code, to do server side because it is cheaper. Another reason - gt its ecosystem. Yet another reason - gt Its lot easier to conduct load tests in nodejs than other scripts. The link you mentioned is work that is intended to be started. Why do not you suggest them that please write this web-assembly compiler in nodejs rather than c/c/assembly because according to you that is superior. C39Mon man, how can you compare Nodejs (A technology) with a C (language) they are not in the same league. C makes node possible, its not visa versa. quotThe main driver to move away from scripting languages was that they were a maintenance nightmare and led to ball of mud applicationsquot -- could you clarify what you mean by scripting languages, and what replacements quotserious developersquot migrated to over the past ten years I was pleased to see a reference to Django in the article and have not run across maintainability issues caused by the use of Python, SQL, or ORMs in general. On the contrary, Python is my go-to language precisely for its maintainability. Your criticisms of js are spot on, but I can39t see how they apply across the entire universe of scripting languages. Well I define scripting languages as runtime compilation languages, but there is a lot of overlap these days. I prefer the reassurance of compile time verification of at least coding accuracy but that is not the only factor. The depth of invasion into the inner workings of the compiler that tend to be exposed by compiled languages these days allow for a whole range of design constructs and patterns that allow programming to be more quotintelligentquot, I just don39t find this level of sophistication in the scripting languages I have used. It is a severe limitation for serious enterprise development. ORMs are an ugly approach to data access on relational databases, but you would probably have to be a database developer to realise why. Data design and Program design have different constraints, ORMs do either an injustice or have to be modified so much that they provide no productivity. There are many issues such as security, isolation, atomic operations that ORMs break, and remember a database is a living system and may require changes in between code releases as a matter of course. ORMs are a blunt tool if you want real performance from your database and want high concurrency without locking. Its a detailed subject I could probably write a book on it, so sorry if this isn39t conclusive enough for you. Can39t say much about Python other than I have heard good things in general. I39m the other end of the market on , I crucify the open source guys next door in productivity and my defect level is about 1 of theirs. I think you need a large system before it makes significant differences, as you need to invest in framework and substrate to get the main benefits back, its quotmass codingquot that is the enemy here. When you have over a 100,000 code files you need a higher level of maintainability as it is simply beyond human capability to do it file by file (and certainly beyond maintenance budgets). By making core services that consume code as content you can achieve a high level of quality while keeping everything granular and ensuring release are small and targeted rather than entire system drops. Each to their own, but if you are an IT pro you must have seen the millions of script based systems festering away in businesses because no one can find anything or understand how it works. It39s such a common complaint I should think it doesn39t need justifying. PD I think quotserious developersquot have migrated to either Java, C or back to C (along with their associated web techs etc). I wasn39t really intending to be derogatory but these three probably account for 90 of all commercial development atm. C wins out on the commercial front for me solely on Microsoft39s considerable ongoing investment and new found modernist approach. C is not very productive and Java is really starting to look a little dated. Still I work in all three and they get the job done, each have their place. P. P.S. quotPython is my go-to language precisely for its maintainabilityquot. What do you consider maintainability It is often not what people think it is (or is not as simple as they think). It encompasses the cost of change and that is the primary cost on the business for a living project. Example: I have a service with 1000 public methods and the business asks me to de-prioritise all calls that take over 2 seconds. If I have to modify any of the code in those 1000 calls then my code has seriously poor maintainability. What I should be making is one code change in my service substrate pipeline. I should not even be modifying the substrate I should be probably writing a statistics module and a de-prioritise module for that substrate loaded in a separate dll that can be loaded dynamically. Now my testing is isolated to just this dll (reverse harness testing) and when ready for release I can add this dll and maybe make one small config change, that39s it, no regression testing and no risk to existing code, so no production bugs in the service methods. So many typical code bases would require all 1000 methods to be altered or at least marked for an AOP operation. Enterprise design requires upfront anticipation of future quotcrazyquot business requests. I find with most scripting languages and even with Java that finding insertion angles later on is nearly impossible. Even if I have a complete mare in C I can emit the code directly into the methods using reflection, I have never seen this level of access on a scripting language and even if it was there it would be dangerous code to emit into runtime compiled operations (because I am literally changing the operations content so I would need to test the result of each). This is just one example I could probably come up with 100s. I39m a technical architect (framework and substrate) so it is my place to quotsavequot my devs from backing themselves into a corner. If I do a good job I can reduce the coding and testing effort to 1 of a quotmass codedquot system. There is a whole other level of development that most devs will never see or appreciate, this means they are never equipped to make the most appropriate technology choices. Interesting article, I39ve got quite a bit of experience in other realms but I39m somewhat new to Node. js. There39s a few things I39d like to clear up: Flash was always async as well, it merely emulated threads much like it sounds like node does by using an event queue. However, I believe it is technical ignorance to claim that trusting thread management to a 3rd or 4th generation language would be better than trusting a well-tuned JRE or operating system optimized for it39s multi-core chipset. How exactly do you think threads work in the lower levels anyway It isn39t some quotmagicquot, the only way to get true simultaneous code execution is via multiple processors, something you simply can39t accomplish with a single thread. It39s also a mistake to say that a new quoteventquot does not add memory or clock cycles taken to a stack just because said events are managed by an interpreted scripting language rather than optimized, compiled C. I39d bet my lunch that a well-written multi-threaded web application written in C or C will blow away any node. js app performance-wise, and that39s even without getting into servers and their current multi-core processor architecture. If you39ve got a quad or 8-core server running a single node thread. you39re only firing on one piston (quite ironic that Google calls their engine quotV8quot when considering such a fact). Another thing to realize is that while Flash (or even Java applets) ran in their own runtimes, so does node -- it39s just hidden to the user. That is nothing more than quotgoodquot (perhaps hostile) business moves on Google39s part. Lets be honest here, if all browsers came with Flash automatically installed on them, and Apple actually supported Flash on their mobile devices, node probably wouldn39t even exist today. I have other concerns about security. What kind of protection does it have against cross-site scripting and other attacks Earlier today I stumbled across a TOR/Bittorrent client that ran in my browser window, and after opening it my computer wouldn39t shut down nicely (it scares me to think what it could have been seeding). No warnings about security or what types of connections my browser window was opening up, just went along with it39s P2P business. the hacker side of me could have a real hay day with those kind of quotfeaturesquot. I doubt that kind of stuff has been tested much either which means there39s a lot of room for bugs, and where there39s a lot of room for bugs there39s a lot of room for vulnerabilities. But hey, at least your entire stack is all in the same language Means you can hire less experienced developers for less money, right ) Good Article for Node JS, you can learn Node JS online in iwebworld. info or send a email iwebworldinfogmail You could remove all the pitfalls of JS by using the its superset aka TypeScript. Tldr Use node for IO-heavy processing and delegating CPU-intensive processing to a cluster of specialized worker nodes (ex database, media processing, etc). This isn39t exactly new information. I covered this topic back in 3912: programmers. stackexchange/a/179499/1256 Ideally, the HTTP and API servers should be mostly stateless (excl session management) and disposable. They39re just a functional pipeline that translates the raw data into consumable representations. That way, the servers are easy to provision/destroy dynamically to meet the spikey nature of demand. I39m not sure why so many of the commenters are vehemently arguing in favor of multi-purpose vertically-scalable server architectures. By nature, vertical scaling will always have an upper limit predicated by hardware capacity. No matter how efficient the code is. The writing is on the wall. You can spend a fortune on hardware and lose sleep questioning the validity of your risk assessment (aka WAG). At the end of the day, bare metal is a fixed asset. Best case, it meets expected demand and justifies the cost. Worst case, it either costs more than it39s worth or lacks the capacity to meet demand. Alternatively, you can embrace distributive computing and automate the infrastructure to grow/contract relative to demand. For the people fighting religious wars over which language is best, node C java. Who cares. All 3 allow 39functional-style39 programming. All 3, support async processing (natively or through extensions). All 3 can be managed via provisioning. All 3 are perfectly valid for building distributive infrastructure. Choosing which one to use depends on the quality of the tools, whether or not it will be used to extend existing infrastructure, and the perception of the client. Build whatever you39re good at building. If you39re really good build whatever is easiest to implement, support, and generate the most profit (or save the most on cost). BTW, kudos to the author. It39s nice to see somebody do a comprehensive (and mostly objective) writeup on this topic. Yes, both languages support horizontal scaling with asynchronous message management infrastructure. CQRS is nothing but an API implementation pattern. CRUD is the typical use case (as it should be) but Node doesn39t automagically scaffold 1:1 mappings between DB and CRUD (see rails/laravel/django for that). Node isn39t a framework at all, it39s just a HTTP server. You can leverage frameworks (ex Express) to more easily leverage the full power of Node but you still have to fine-tune your routes to define a fully functional API. Net Reactive Extensions have been ported to JS: www. npmjs/package/rx In fact, even LINQ has been ported to JS (yes, seriously). linqjs. codeplex/ ORMs are only an issue because they require an additional layer of abstraction from the underlying data. If (read when) the data models need to change to adapt to business demands, both the ORM and the database schema will need to be updated and tested to reflect the changes. Which is not really a big deal if there39s a good update strategy in place. As for the rest of your comment, you39d do well if you stepped out of your comfort zone once in a while to see how JS development really works. 1. JS classes are currently supported now via ES6 (also, available client-side via polyfills). Prototypes really aren39t much different than classes in terms of encapsulation (except they39re a lot more flexible). Compile-time static type checking is even supported via TypeScript/Dart if that39s what floats your boat, it39s just not the default. 2. TDD/BDD isn39t a feature exclusive to statically typed languages. There are a lot of great testing frameworks available in JS (both server/client-side). Choose your flavor, unit testing (Mocha), behavior driven unit testing (Chai), api testing (SuperTest), and continuous integration testing (TravisCI, and many others) are all used extensively throughout the community. JSUnit (the JS equivalent of JUnit/NUnit) is even available if you miss unit testing in Java/. If anything, testing is a basic requirement of any non-trivial JS app that goes into production because you don39t have a compile-time type checker to hold your hand. 3. Complex workflow Seriously So, you39ve never heard of NPM scripting, grunt, gulp Automating any-and-everything in JS is pretty easy. Style enforcement, linting, documentation generation, scaffolding, one-click-deployment, language transpilation, bundling, distribution building, package/dependency management, release management, etc. 4. cringe: if you rely on the compile-time static type checking system alone to validate user input, you39re doing it wrong. Building a data layer in any language requires constraints above-and-beyond what the default types provide. So, either way you39ll have to extend your data models with custom validation checks. The cool part about handling validation in JS is you can use the same routines to check user input on both the client/server-side. Less duplication of effort FTW. Contrary to what you think. Javascript really is a 39one size fits all39 approach if you prefer to use it as such. Seriously, you can even compile C/C directly to javascript using asm. js. Does that mean you have to use it Of course not. Any developer with a speck of sense wouldn39t fault you for choosing C, it39s a great language. I have experience writing code in many languages, including building non-trivial desktop applications in C. Given a choice, I39d prefer to use Javascript. The mix of, looser constraints and functional/imperative/prototype styles allow for a level of creativity I haven39t experienced in any other language. The tools are great, the module system is amazing, and the language itself is getting substantially better with each update. Upload Files: howtonode. org/really-simple-file-uploads quotAll the I/O operations is handled by Node. js is using multiple threads internally it39s the programming interface to that I/O functionality that39s single threaded, event-based, and asynchronous. quot stackoverflow/a/22981768/290340 Libuv uses a thread-pool to handle I/O operations (files, sockets, etc) in an asynchronous manner. Where most languages block by default during CPU-heavy I/O operations, Node doesn39t. It simply fires an event when the I/O operation completes on the worker thread. Active Directory: github/gheeres/node-activedirectory github/auth0/passport-windowsauth The distinction is that Node is async by default So, the number of developers doing async programming in other languages are the minority so they39re not as well represented. quotI can39t come up with any good reason to use it on the server side in favor to other available languages. quot Not gonna lie, using Node at first was. Challenging to say the least. Getting used to async-by-default is not an easy transition. The nice part Node is, the primary focus of the platform is building servers/clients so the ecosystem has a lot of powerful tools to do anything dealing with web development. quot. have better standard libraries, tools and resources. quot I39m not sure what gave you that impression. It doesn39t use the monolithic-everything-and-the-kitchen-sink base class library approach. The core itself is very small but that39s a benefit as it39s much lighter to deploy. It also includes a very powerful, full-featured package manager by default so you39re expected to add the dependencies your project needs. NPM (Node Package Manager) has over 200K packages and counting. Since the majority of the modules are developed independently from the core, they iterate and improve much faster than the equivalent core libraries in other languages. Dependencies are managed locally on a per-project basis in the package. json file. Typically, it39s bad form for a module author to require that their package be installed globally. Installing packages locally prevents version conflicts at the global level and guarantees that -- when you install a package -- everything required to use the module is included. It may seem inefficient at first glance because many dependencies may have copies of the same sub-dependencies (or sub-subdeps, etc) but compared to the cost of including a massive standard library, the storage space is insignificant. The workflow to setup a project is: - clone the source - run 39npm install39 NPM will automatically download and install all of the dependencies (incl sub-deps, sub-sub-deps, etc). Since the dependencies (and their specific versions) are explicitly defined in the config, you don39t need to check them into source control. In addition, with ES6 (incl the new ES6-module-loader) about to be released, a new JSPM (Javascript Package Manager) has been created to manage client-side javascript dependencies. Module imports in the browser have finally been formalized in the language spec, so Bower and the variety of module-loading pseudo-standards (ex AMD, CommonJS, UMD) will go away. As said above modern OO languages have a vast array of options to formalize and control your code and solutions that are lacking in scripting languages. That39s just the plain truth, no amount of griping is going to change that. My point is there are a lot of developers choosing technology by popularity rather than suitability, that39s what makes them fan boys. Right tool for the right job, applies in every trade apart from software development apparently. But that is probably because most developers aren39t true quotTradesmanquot, more glorified quotDIY39ersquot. The industry is full of amateurs who don39t even know enough to know that they know nothing They think because they can write an if statement and a while loop they are pros. Techno-weenies. System level I/O operations (such as files, sockets) in Node are handled by libuv which does use a background thread pool. The difference is, the main thread can fire and forget the task to a background thread and the background thread will notify the main thread (via firing an event) when the operation is completed. Even with background thread processing, doing lots of I/O operations doesn39t scale very well. For long-running CPU-heavy tasks (ex image/movie encoding) offloading the tasks to worker nodes is still preferable. In most languages, I/O operations are handled in a synchronous manner so if they requests are made on the main thread, they39ll block execution until completed. The reason you don39t see a noticeable pause in the UI when this happens is because the UI is asynchronous/event-based and runs on a thread separate from the main context. There39s nothing stopping you from exposing the API as a microservice. WebKit just allows you to run a native JS client. I may be wrong but from what I understand, unlike the browser a webkit client isn39t as strictly sandboxed so you can make system calls (ex to open/save files without user input). I think you made my point for me, frothing unthinking, emotional nonsense, with very little in the way of fact, from a mind so fanatic about one thing it can39t even see its failings. You seem to have made a fair few assumptions about what I do and don39t know, I have been doing Javascript for 20 years, I know its short comings, I can work effectively in probably 30 languages, I use what is appropriate, I never indicated otherwise. You need to grow up or find a new industry to work in. People like you are the problem with Software Development, no nothing nobodies who can39t even make a case for a technology, let alone use one. Please stay away from the keyboard and do the rest of us a favour. Do you use version control with a standard workflow (ex Gitflow workflow) where developers make changes on feature branches and code is peer reviewed before being merged I39ve been messing around with trying to build an Angular2 website lately and the Angular2 project is still in early alpha so breaking changes are a regular (albeit unfortunate) occurrence. All of the available examples online are pretty-much broken so I39ve been monitoring the project development on Github. The rate that the core developers are thrashing on the codebase is truly remarkable. What39s even more amazing is that every PR is unit tested and continuous integration tested well enough that every release is guaranteed to be fully functional (as far as they39ve implemented it so far). Following what Tracker1 is saying. Linting is the equivalent of compile-time checking in JS. I even use a Sublime extension that shows linter errors directly in the gutter of the editor as I39m writing code. If you want stricter checking you can add a style checker such as 39semistandard39 which guarantees code styling on a project-wide basis. That means, spaces-not-tabs, indent 2 spaces, consistent functions, curly braces, etc. Type checking is good for superficial bugs (ex uninitialized variables, dead branches, invalid values) but eventually you39ll have to verify the code doesn39t have logic bugs through unit testing, continuous integration testing, api testing. Node uses async event-based I/O via libuv (incl a thread pool reserved for I/O requests). The main thread absolutely does not block during I/O operations. It works the same way cluster would except it39s built into Node. Check out one of the presentations on libuv for more details. Performance wise, PayPal seems to think good things about Node dongnotes. blogspot/2013/12/paypals-nodejs-versus-java-benchmark For security, the 39cors39 module is pluggable to Express and can be used for all the usual CORS control stuff. The 39helmet39 module -- also pluggable to Express -- exposes a small suite of features to protect against malicious users including additional cross site scripting protection. I39m not sure if I39d call a Fullstack JS dev 39inexperienced39. Having a solid understanding of multiple domains in a development ecosystem that is constantly evolving is maddening. ya know, quot10 years of experience vs 1 year of experience 10 timesquot. Node. js hasn39t even been around for 10 years (which is funny considering I have seen job postings actually asking for 10 years experience with it). I understand that following evolving technology is a challenge, and after 20 years I can tell you that by the time you get completely comfortable with any quotfull stackquot it will be less relevant because technology is always advancing. Nothing will change that, it39s just how things work. However, you can39t really have your cake and eat it too there. Newer technology is less tested and therefore less secure, but older technology does not have as many features. There39s always a trade-off there. Anybody who claims otherwise is selling you something. I am sold on Node. JS (if your application is into building high scalability networking applications), Node. JS is the way to go in 2015. No wonder why so many startups and large corporations are adopting it. C, Java, Ruby and Python havew their place in their respective domains. New companies and products will be getting built on wide variety of languages. I predict ROR adoption would still be high in coming years for building web applications (simply because ROR developers are easily available and time to market is so small). Excellent article though Tomislav. So true My job is the maintainance of legacy apps usually SQL Server dB39s ms access or pop fronteds. These were usually made by quotthe grandson who is good with computersquot Kind of guy. No foreign keys, but custom date time functions. Your post is my sentiment exactly I find Java very unproductive and very expensive for a lot of low level tedious work. C is for programmers who can handle memory access/pointers. Most corporate programmers cannot. Back in the day you had PL/1 and C for software engineers and COBOL for information technology programmers. Gracias. this is so helpful as i am going to make a heavy-computation enterprise application. i think i39ll try node. js on other application. for now, i39ll use ruby on rails When this article was written Thanks for this article I think than the argument of same langage for front and dev is the worst I can liste or read. Organized good coding with js is the more horrible things append in a team. I work since last year on backend project and where this should be coded in some times with mature framework like django it took too much time understand hundreds bugs. Where mongodb feels cool. Nunca. I realy thinks than nodejs is a big joke and not So cool. The package manager give us some cool package to patch and hide the bad side of node but there is nothing to do about the callback hell. Finally the code looks like a big sand box than i hatte to open a file for debug or add some lines of code. So my conclusion is than for small app why not but for big and evolutive project not use nor nodejs and mongodb. Regards This is a fairly ill-informed comment as ES6 was alive and well as at a year ago. Besides the OO from ES6, there is also TypeScript which adds even more enterprise-level OO to JavaScript. Like is compiled, TypeScript may also be quottranspiledquot to Javascript. NodeJS allows for pretty much of all this now with an even still better utilization of server resources and no OS lock-in. Think cutting your infrastructure costs by 2000 because you really shouldn39t need to scale too vertically or pay for that license per node. Fintech companies like Paypal are happily doing great things with node as well so I highly doubt this comment of yours comes from a place of non-ignorance about what NodeJS eco-system truly offers the enterprising product. David M Tromholt Yeah it would be nice with a date. I assume they don39t show it because they know how biased people are towards new information but it doesn39t make much sense to hide it in an article about a fast growing technology. Hi Avinash, Can you please eloborate little more on your statement. I am trying to understand more on this. Would node be a bad idea for something like 9gag then Would you need to do any image manipulation on a different server to prevent blocking Hey Tomislav, Great article I wanted to know that if suppose I want to get external hardware output in my app, e. g, scanner or e-signature (if user is doing e-signature or getting scanned copy from scanner), then can i get directly in my app it will be like an api call as we do in Java.
