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Writing robust Node.js applications

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Tom Croucher

This document provides an introduction and overview of a Node.js tutorial presented by Tom Hughes-Croucher. The tutorial covers topics such as building scalable server-side code with JavaScript using Node.js, debugging Node.js applications, using frameworks like Express.js, and best practices for deploying Node.js applications in production environments. The tutorial includes exercises for hands-on learning and demonstrates tools and techniques like Socket.io, clustering, error handling and using Redis with Node.js applications.

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Node.js Tutorial Tom Hughes-Croucher, Principal Jetpacks For Dinosaurs, LLC tom@jetpacksfordinosaurs.com @sh1mmer
Introduction • Tom Hughes-Croucher • Principal at Jetpacks for Dinosaurs • Node.js and High-performance web site consulting and training • Walmart, MySpace, Joyent,Yahoo!, NASA, Tesco, etc • Node.js contributor • Lead author of "Node: Up and Running"
Scalable Server-Side Code with JavaScript Node Up and Running Tom Hughes-Croucher http://ofps.oreilly.com/titles/9781449398583/ http://shop.oreilly.com/product/0636920015956.do
Training Online In person
Node refresher
Code!
Interactive Debugging
Enki:~/Code/node-examples $ node --debug helloworld.js debugger listening on port 5858 Server running at http://127.0.0.1:8124/
enki:~ sh1mmer$ ps -A | grep node 19093 ttys001 0:00.39 node index.js 19273 ttys002 0:00.00 grep node enki:~ sh1mmer$ kill -s USR1 19093
enki:~ sh1mmer$ node index.js Hit SIGUSR1 - starting debugger agent. debugger listening on port 5858
Enki:~ $ sudo npm install -g node-inspector node-inspector@0.1.8 ./node_modules/node-inspector ├── websocket-server@1.4.04 └── paperboy@0.0.2 Enki:~ $ node-inspector visit http://0.0.0.0:8080/debug?port=5858 to start debugging
Writing robust Node.js applications
Exercises • Modify a basic HTTP server to return the text "I'm learning Node" • Change the HTTP response to HTML and return your text in an HTML page • Return the User-Agent string from the browser as part of your HTML page
Express.js
Sinatra Style MVC framework
var app = require('express').createServer(); app.get('/', function(req, res){ res.send('hello world'); }); app.listen(3000);
HTTP Verb Oriented
Middleware
app.use(express.bodyParser()); app.use(express.cookieParser()); app.post('/', function(req, res){ // Perhaps we posted several items with a form // (use the bodyParser() middleware for this) var items = req.body.items; console.log(items); res.send('logging'); });
Templating
var express = require("express"); app.configure(function () { var public = __dirname + "/../public/"; public = require("path").normalize(public); app.set("views", __dirname + "/views"); app.set("view engine", "jade"); }); app.get("/", function (req, res) { res.render("index", { locals : { h1: 'Router Stats', scripts : [ "/public/smoothie.js", "/public/raphael.js", "/public/base.js", "/public/gfx.js", "/public/explore.js", "/public/app.js" ] } } });
Exercise • Create an Express server • Make routes for ‘/’ & ‘/products’ • Serve two different pages based on value of the query string parameter "page" • Create a redirect from /old to /new • Set a cookie on the client
Building a chat server
Node Architectures
The obvious architecture
Client Front-end Database User Node DB
What about this?
Heavy Front-end Client Processor Database Farm Work User Node Node Node Node DB Node Node Node Node
Don’t we want to move “heavy work”?
Client → Server Server → DB Computation Computation
Better architecture
Front-end Client Database Farm DB User Node Node Node Node Big Slow Logging farm Disk Node Node Disk
Move work which isn’t user-facing out of main event loop
Ensure consistency of Node processes
Distributing work
Cluster
var cluster = require('cluster'); var http = require('http'); var numCPUs = require('os').cpus().length; if (cluster.isMaster) { // Fork workers. for (var i = 0; i < numCPUs; i++) { cluster.fork(); } cluster.on('death', function(worker) { console.log('worker ' + worker.pid + ' died'); }); } else { // Worker processes have a http server. http.Server(function(req, res) { res.writeHead(200); res.end("hello worldn"); }).listen(8000); }
Use load balancers to distribute across servers
node-proxy squid varnish haproxy
Unbundle SSL stud, stunnel, etc http://vincent.bernat.im/en/blog/2011- ssl-benchmark.html#conclusion
Sharding
Disclaimer: Sharding is hard See CAP theorem
Socket.io
Web Socket library
client and server with the shared API
var app = require('express').createServer(), io = require('socket.io').listen(app); app.listen(80); app.get('/', function (req, res) {   res.sendfile(__dirname + '/index.html'); }); io.sockets.on('connection', function (socket) {   socket.emit('news', { hello: 'world' });   socket.on('my other event', function (data) {     console.log(data);   }); });
<!DOCTYPE html> <html> <body> <script src="/socket.io/socket.io.js"></script> <script> var socket = io.connect('http://localhost'); socket.connect(); socket.on('connect', function(){ console.log('connect') }) socket.on('message', function(){ console.log('message') }) socket.on('disconnect', function(){ console.log('disconnect'); }) </script> </body> </html>
Transports • WebSocket • Adobe® Flash® Socket • AJAX long polling • AJAX multipart streaming • Forever iframe • JSONP Polling
options = { transports: ['websocket'], log: util.log } io.listen(server, options)
// note, io.listen() will create a http server for you var io = require('socket.io').listen(80); io.sockets.on('connection', function (socket) {   io.sockets.emit('this', { will: 'be received by everyone'});   socket.on('private message', function (from, msg) {     console.log('I received a private message by ', from, ' saying ', msg);   });   socket.on('disconnect', function () {     sockets.emit('user disconnected');   }); });
Exercises • Create a socket.io connect to an express server • Create a route which loads a page that includes socket.io • Send "hello world" to the client sockets • Make the client respond with "thanks" and disconnect from the server
Using Redis with Socket.io
Why use Redis? • No shared memory • Cluster on server won’t share client data • Multiple servers can use the same Redis
var express = require('express') , app = express.createServer(); var sio = require('socket.io') , RedisStore = sio.RedisStore , io = sio.listen(app); app.listen(8080); app.get('/', function(req,res) { res.sendfile(__dirname + '/index.html'); }); io.sockets.on('connection', function (socket) { socket.on('chat', function (data) { console.log(data); socket.broadcast.emit('chat', data); }) });
var cluster = require('cluster'); var http = require('http'); var numCPUs = require('os').cpus().length; if (cluster.isMaster) { // Fork workers. for (var i = 0; i < numCPUs; i++) { cluster.fork(); } } else { var express = require('express') , app = express.createServer(); var sio = require('socket.io') , RedisStore = sio.RedisStore , io = sio.listen(app); app.listen(8080); app.get('/', function(req,res) { res.sendfile(__dirname + '/index.html'); }); // Somehow pass this information to the workers io.set('store', new RedisStore); // Do the work here io.sockets.on('connection', function (socket) { socket.on('chat', function (data) { console.log(data); socket.broadcast.emit('chat', data); }) }); }
Node in production
Error handling
var http = require('http'); var req = http.request({ host: 'www.google.com', path: '/', port: 80, method: 'POST' }, function (response) { // Do stuff with the response here });
node.js:134 throw e; // process.nextTick error, or 'error' event on first tick ^ Error: Uncaught, unspecified 'error' event. at EventEmitter.emit (events.js:47:15) at Object.<anonymous> (/ Users/you/y-u-no-listen-for-errors.js:5:9) at Module._compile (module.js:404:26) at Object..js (module.js:410:10) at Module.load (module.js:336:31) at Function._load (module.js:297:12) at Array.<anonymous> (module.js:423:10) at EventEmitter._tickCallback (node.js:126:26)
var http = require('http'); try { var req = http.request({ host: 'www.google.com', path: '/', port: 80, method: 'POST' }, function (response) { // Do stuff with the response here }); } catch(e) {
var http = require('http'); var req = http.request({ host: 'www.google.com', path: '/', port: 80, method: 'POST' }, function (response) { // Do stuff with the response here }); req.on('error', function (err) { //safely handle this if possible });
// Suppress errors process.on('uncaughtException', function (err) { // Log it! console.dir(err); });
EventEmitter leaks
(node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit. Trace: at Pool.<anonymous> (events.js:101:17) at Object.proxyRequest (~/http-proxy/lib/node-http-proxy.js:185:7) at Server.<anonymous> (/Users/some-user/myapp.js:14:9) at Server.emit (events.js:45:17) at HTTPParser.onIncoming (http.js:1078:12) at HTTPParser.onHeadersComplete (http.js:87:31) at Socket.ondata (http.js:977:22) at Socket._onReadable (net.js:654:27) at IOWatcher.onReadable [as callback] (net.js:156:10)
var events = require('events'); function doSomethingThenTellMe () { var emitter = new events.EventEmitter(); setTimeout(function () { emitter.emit('done'); }, 2000); return emitter; } var doingIt = doSomethingThenTellMe(); doingIt.on('done', function () { console.log("Ok, it's done"); }); // Why are you using `.on()`? // You only expect this event to fire once.
once() is awesome
var events = require('events'); function doSomethingThenTellMe () { var emitter = new events.EventEmitter(); setTimeout(function () { emitter.emit('done'); }, 2000); return emitter; } var doingIt = doSomethingThenTellMe(); doingIt.once('done', function () { console.log("Ok, it's done"); });
Process monitoring
Upstart
description "node.js server" author "croucher`" start on startup stop on shutdown script # We found $HOME is needed. Without it, we ran into problems export HOME="/root" exec /usr/local/bin/node /var/noderoot/index.js 2>&1 >> / var/log/node.log end script
forever
$ cd /path/to/your/app $ forever start bin/yourapp info: Running action: start info: Forever processing file: examples/server.js $ forever list info: Running action: list info: Forever processes running [0] bin/yourapp [77041, 77040] /Users/You/.forever 20dL.log 0:0:0:1.788
NPM Packaging
Enki:~/Code/node-dnsserve(master) $ ls LICENSE README dnsserver.js package.json Enki:~/Code/node-dnsserve(master) $
{ "name": "dns-server", "description": "DNS server for Node", "version": "0.0.1a", "author": "Tom Hughes-Croucher <tom.croucher@gmail.com>", "main" : "dnsserver" }
Enki:~/Code/node-dnsserve(master) $ sudo npm install . -g dns-server@0.0.1a /usr/local/lib/node_modules/dns- server Enki:~/Code/node-dnsserve(master) $
Enki:~/Code/node-dnsserve(master) $ sudo npm link /usr/local/lib/node_modules/dns-server -> /Users/sh1mmer/Code/ node-dnsserve Enki:~/Code/node-dnsserve(master) $ npm ls -g /usr/local/lib ├── dns-server@0.0.1a -> /Users/sh1mmer/Code/node-dnsserve └─┬ npm@1.0.6 ├── abbrev@1.0.3 ├── node-uuid@1.1.0 ├── nopt@1.0.4 └── semver@1.0.5 Enki:~/Code/node-dnsserve(master) $
Enki:~/Code/node-dnsserve(master) $ npm adduser Username: foobarbaz Password: Email:
Enki:~/Code/node-dnsserve(master) $ npm publish npm WARN Sending authorization over insecure channel. Enki:~/Code/node-dnsserve(master) $
{ "name": "winston", "description": "A multi-transport async logging library for Node.js", "version": "0.2.7", "author": "Charlie Robbins <charlie.robbins@gmail.com>", "contributors": [ { "name": "Matthew Bergman", "email": "mzbphoto@gmail.com" } ], "repository": { "type": "git", "url": "http://github.com/indexzero/winston.git" }, "keywords": ["logging", "sysadmin", "tools"], "dependencies": { "colors": ">= 0.3.0", "eyes": ">= 0.1.6", "loggly": ">= 0.1.4", "vows": ">= 0.5.2" }, "main": "./lib/winston", "scripts": { "test": "vows test/*-test.js --spec" }, "engines": { "node": ">= 0.3.0" } }
{ "name": "winston", "description": "A multi-transport async logging library for Node.js", "version": "0.2.7", "author": "Charlie Robbins <charlie.robbins@gmail.com>", "contributors": [ { "name": "Matthew Bergman", "email": "mzbphoto@gmail.com" } ], "repository": { "type": "git", "url": "http://github.com/indexzero/winston.git" }, "keywords": ["logging", "sysadmin", "tools"], "dependencies": { "colors": ">= 0.x.x", "eyes": ">= 0.1.x", "loggly": ">= 0.1.x", "vows": ">= 0.5.x" }, "main": "./lib/winston", "scripts": { "test": "vows test/*-test.js --spec" }, "engines": { "node": ">= 0.3.0" } }
Questions tom@jetpacksfordinosaurs.com @sh1mmer

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Writing robust Node.js applications

  • 1. Node.js Tutorial Tom Hughes-Croucher, Principal Jetpacks For Dinosaurs, LLC [email protected] @sh1mmer
  • 2. Introduction • Tom Hughes-Croucher • Principal at Jetpacks for Dinosaurs • Node.js and High-performance web site consulting and training • Walmart, MySpace, Joyent,Yahoo!, NASA, Tesco, etc • Node.js contributor • Lead author of "Node: Up and Running"
  • 3. Scalable Server-Side Code with JavaScript Node Up and Running Tom Hughes-Croucher http://ofps.oreilly.com/titles/9781449398583/ http://shop.oreilly.com/product/0636920015956.do
  • 4. Training Online In person
  • 8. Enki:~/Code/node-examples $ node --debug helloworld.js debugger listening on port 5858 Server running at http://127.0.0.1:8124/
  • 9. enki:~ sh1mmer$ ps -A | grep node 19093 ttys001 0:00.39 node index.js 19273 ttys002 0:00.00 grep node enki:~ sh1mmer$ kill -s USR1 19093
  • 10. enki:~ sh1mmer$ node index.js Hit SIGUSR1 - starting debugger agent. debugger listening on port 5858
  • 11. Enki:~ $ sudo npm install -g node-inspector [email protected] ./node_modules/node-inspector ├── [email protected] └── [email protected] Enki:~ $ node-inspector visit http://0.0.0.0:8080/debug?port=5858 to start debugging
  • 13. Exercises • Modify a basic HTTP server to return the text "I'm learning Node" • Change the HTTP response to HTML and return your text in an HTML page • Return the User-Agent string from the browser as part of your HTML page
  • 15. Sinatra Style MVC framework
  • 16. var app = require('express').createServer(); app.get('/', function(req, res){ res.send('hello world'); }); app.listen(3000);
  • 19. app.use(express.bodyParser()); app.use(express.cookieParser()); app.post('/', function(req, res){ // Perhaps we posted several items with a form // (use the bodyParser() middleware for this) var items = req.body.items; console.log(items); res.send('logging'); });
  • 21. var express = require("express"); app.configure(function () { var public = __dirname + "/../public/"; public = require("path").normalize(public); app.set("views", __dirname + "/views"); app.set("view engine", "jade"); }); app.get("/", function (req, res) { res.render("index", { locals : { h1: 'Router Stats', scripts : [ "/public/smoothie.js", "/public/raphael.js", "/public/base.js", "/public/gfx.js", "/public/explore.js", "/public/app.js" ] } } });
  • 22. Exercise • Create an Express server • Make routes for ‘/’ & ‘/products’ • Serve two different pages based on value of the query string parameter "page" • Create a redirect from /old to /new • Set a cookie on the client
  • 23. Building a chat server
  • 26. Client Front-end Database User Node DB
  • 28. Heavy Front-end Client Processor Database Farm Work User Node Node Node Node DB Node Node Node Node
  • 29. Don’t we want to move “heavy work”?
  • 30. Client → Server Server → DB Computation Computation
  • 32. Front-end Client Database Farm DB User Node Node Node Node Big Slow Logging farm Disk Node Node Disk
  • 33. Move work which isn’t user-facing out of main event loop
  • 34. Ensure consistency of Node processes
  • 37. var cluster = require('cluster'); var http = require('http'); var numCPUs = require('os').cpus().length; if (cluster.isMaster) { // Fork workers. for (var i = 0; i < numCPUs; i++) { cluster.fork(); } cluster.on('death', function(worker) { console.log('worker ' + worker.pid + ' died'); }); } else { // Worker processes have a http server. http.Server(function(req, res) { res.writeHead(200); res.end("hello worldn"); }).listen(8000); }
  • 38. Use load balancers to distribute across servers
  • 39. node-proxy squid varnish haproxy
  • 40. Unbundle SSL stud, stunnel, etc http://vincent.bernat.im/en/blog/2011- ssl-benchmark.html#conclusion
  • 42. Disclaimer: Sharding is hard See CAP theorem
  • 45. client and server with the shared API
  • 46. var app = require('express').createServer(), io = require('socket.io').listen(app); app.listen(80); app.get('/', function (req, res) {   res.sendfile(__dirname + '/index.html'); }); io.sockets.on('connection', function (socket) {   socket.emit('news', { hello: 'world' });   socket.on('my other event', function (data) {     console.log(data);   }); });
  • 47. <!DOCTYPE html> <html> <body> <script src="/socket.io/socket.io.js"></script> <script> var socket = io.connect('http://localhost'); socket.connect(); socket.on('connect', function(){ console.log('connect') }) socket.on('message', function(){ console.log('message') }) socket.on('disconnect', function(){ console.log('disconnect'); }) </script> </body> </html>
  • 48. Transports • WebSocket • Adobe® Flash® Socket • AJAX long polling • AJAX multipart streaming • Forever iframe • JSONP Polling
  • 49. options = { transports: ['websocket'], log: util.log } io.listen(server, options)
  • 50. // note, io.listen() will create a http server for you var io = require('socket.io').listen(80); io.sockets.on('connection', function (socket) {   io.sockets.emit('this', { will: 'be received by everyone'});   socket.on('private message', function (from, msg) {     console.log('I received a private message by ', from, ' saying ', msg);   });   socket.on('disconnect', function () {     sockets.emit('user disconnected');   }); });
  • 51. Exercises • Create a socket.io connect to an express server • Create a route which loads a page that includes socket.io • Send "hello world" to the client sockets • Make the client respond with "thanks" and disconnect from the server
  • 52. Using Redis with Socket.io
  • 53. Why use Redis? • No shared memory • Cluster on server won’t share client data • Multiple servers can use the same Redis
  • 54. var express = require('express') , app = express.createServer(); var sio = require('socket.io') , RedisStore = sio.RedisStore , io = sio.listen(app); app.listen(8080); app.get('/', function(req,res) { res.sendfile(__dirname + '/index.html'); }); io.sockets.on('connection', function (socket) { socket.on('chat', function (data) { console.log(data); socket.broadcast.emit('chat', data); }) });
  • 55. var cluster = require('cluster'); var http = require('http'); var numCPUs = require('os').cpus().length; if (cluster.isMaster) { // Fork workers. for (var i = 0; i < numCPUs; i++) { cluster.fork(); } } else { var express = require('express') , app = express.createServer(); var sio = require('socket.io') , RedisStore = sio.RedisStore , io = sio.listen(app); app.listen(8080); app.get('/', function(req,res) { res.sendfile(__dirname + '/index.html'); }); // Somehow pass this information to the workers io.set('store', new RedisStore); // Do the work here io.sockets.on('connection', function (socket) { socket.on('chat', function (data) { console.log(data); socket.broadcast.emit('chat', data); }) }); }
  • 58. var http = require('http'); var req = http.request({ host: 'www.google.com', path: '/', port: 80, method: 'POST' }, function (response) { // Do stuff with the response here });
  • 59. node.js:134 throw e; // process.nextTick error, or 'error' event on first tick ^ Error: Uncaught, unspecified 'error' event. at EventEmitter.emit (events.js:47:15) at Object.<anonymous> (/ Users/you/y-u-no-listen-for-errors.js:5:9) at Module._compile (module.js:404:26) at Object..js (module.js:410:10) at Module.load (module.js:336:31) at Function._load (module.js:297:12) at Array.<anonymous> (module.js:423:10) at EventEmitter._tickCallback (node.js:126:26)
  • 60. var http = require('http'); try { var req = http.request({ host: 'www.google.com', path: '/', port: 80, method: 'POST' }, function (response) { // Do stuff with the response here }); } catch(e) {
  • 61. var http = require('http'); var req = http.request({ host: 'www.google.com', path: '/', port: 80, method: 'POST' }, function (response) { // Do stuff with the response here }); req.on('error', function (err) { //safely handle this if possible });
  • 62. // Suppress errors process.on('uncaughtException', function (err) { // Log it! console.dir(err); });
  • 64. (node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit. Trace: at Pool.<anonymous> (events.js:101:17) at Object.proxyRequest (~/http-proxy/lib/node-http-proxy.js:185:7) at Server.<anonymous> (/Users/some-user/myapp.js:14:9) at Server.emit (events.js:45:17) at HTTPParser.onIncoming (http.js:1078:12) at HTTPParser.onHeadersComplete (http.js:87:31) at Socket.ondata (http.js:977:22) at Socket._onReadable (net.js:654:27) at IOWatcher.onReadable [as callback] (net.js:156:10)
  • 65. var events = require('events'); function doSomethingThenTellMe () { var emitter = new events.EventEmitter(); setTimeout(function () { emitter.emit('done'); }, 2000); return emitter; } var doingIt = doSomethingThenTellMe(); doingIt.on('done', function () { console.log("Ok, it's done"); }); // Why are you using `.on()`? // You only expect this event to fire once.
  • 67. var events = require('events'); function doSomethingThenTellMe () { var emitter = new events.EventEmitter(); setTimeout(function () { emitter.emit('done'); }, 2000); return emitter; } var doingIt = doSomethingThenTellMe(); doingIt.once('done', function () { console.log("Ok, it's done"); });
  • 70. description "node.js server" author "croucher`" start on startup stop on shutdown script # We found $HOME is needed. Without it, we ran into problems export HOME="/root" exec /usr/local/bin/node /var/noderoot/index.js 2>&1 >> / var/log/node.log end script
  • 72. $ cd /path/to/your/app $ forever start bin/yourapp info: Running action: start info: Forever processing file: examples/server.js $ forever list info: Running action: list info: Forever processes running [0] bin/yourapp [77041, 77040] /Users/You/.forever 20dL.log 0:0:0:1.788
  • 74. Enki:~/Code/node-dnsserve(master) $ ls LICENSE README dnsserver.js package.json Enki:~/Code/node-dnsserve(master) $
  • 75. { "name": "dns-server", "description": "DNS server for Node", "version": "0.0.1a", "author": "Tom Hughes-Croucher <[email protected]>", "main" : "dnsserver" }
  • 76. Enki:~/Code/node-dnsserve(master) $ sudo npm install . -g [email protected] /usr/local/lib/node_modules/dns- server Enki:~/Code/node-dnsserve(master) $
  • 77. Enki:~/Code/node-dnsserve(master) $ sudo npm link /usr/local/lib/node_modules/dns-server -> /Users/sh1mmer/Code/ node-dnsserve Enki:~/Code/node-dnsserve(master) $ npm ls -g /usr/local/lib ├── [email protected] -> /Users/sh1mmer/Code/node-dnsserve └─┬ [email protected] ├── [email protected] ├── [email protected] ├── [email protected] └── [email protected] Enki:~/Code/node-dnsserve(master) $
  • 78. Enki:~/Code/node-dnsserve(master) $ npm adduser Username: foobarbaz Password: Email:
  • 79. Enki:~/Code/node-dnsserve(master) $ npm publish npm WARN Sending authorization over insecure channel. Enki:~/Code/node-dnsserve(master) $
  • 80. { "name": "winston", "description": "A multi-transport async logging library for Node.js", "version": "0.2.7", "author": "Charlie Robbins <[email protected]>", "contributors": [ { "name": "Matthew Bergman", "email": "[email protected]" } ], "repository": { "type": "git", "url": "http://github.com/indexzero/winston.git" }, "keywords": ["logging", "sysadmin", "tools"], "dependencies": { "colors": ">= 0.3.0", "eyes": ">= 0.1.6", "loggly": ">= 0.1.4", "vows": ">= 0.5.2" }, "main": "./lib/winston", "scripts": { "test": "vows test/*-test.js --spec" }, "engines": { "node": ">= 0.3.0" } }
  • 81. { "name": "winston", "description": "A multi-transport async logging library for Node.js", "version": "0.2.7", "author": "Charlie Robbins <[email protected]>", "contributors": [ { "name": "Matthew Bergman", "email": "[email protected]" } ], "repository": { "type": "git", "url": "http://github.com/indexzero/winston.git" }, "keywords": ["logging", "sysadmin", "tools"], "dependencies": { "colors": ">= 0.x.x", "eyes": ">= 0.1.x", "loggly": ">= 0.1.x", "vows": ">= 0.5.x" }, "main": "./lib/winston", "scripts": { "test": "vows test/*-test.js --spec" }, "engines": { "node": ">= 0.3.0" } }

Editor's Notes