Essential Books

Adding Middleware

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Middleware functions are functions that have access to the request object (req), the response object (res), and the next middleware function in the application’s request-response cycle.

Middleware functions can execute any code, make changes to res and req objects, end response cycle and call next middleware.

Very common example of middleware is cors module. To add CORS support, simply install it, require it and put this line: 

app.use(cors());

before any routers or routing functions.

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Web apps with Express:
* Web Apps With Express
* Getting Started
* Basic routing
* Modular express application
* Using a Template Engine
* Serving static files
* JSON API with ExpressJS
* Getting info from the request
* Error Handling
* Adding Middleware
* Hook How to execute code before any req and after any res
* Error handling in Express
* Hello World
* Named routes in Django-style
* Setting cookies with cookie-parser
* Custom middleware in Express
* Handling POST Requests
* Error handling
* Using middleware and the next callback
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0 Getting started
1 npm
2 Web apps with Express
3 Filesystem I/O
4 Exporting and consuming modules
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25 async.js
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28 Mongodb integration
29 Handling POST requests in Node.js
30 Simple REST based CRUD API
31 Template frameworks
32 Node.js architecture inner workings
33 Debugging
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36 Interacting with console
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48 Node.js design fundamental
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50 Performance challenges
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52 Remote debugging in node.js
53 MySQL connection pool
54 Database MongoDB with Mongoose
55 Good coding style
56 RESTful API design best practices
57 Deliver HTML or other file
58 TCP Sockets
59 Hack
60 Blueburid promises
61 Async / Await
62 Koa Framework v2
63 Unit testing frameworks
64 ES6
65 Routing AJAX requests with Express.JS
66 Sending a file stream to client
67 Redis
68 Using browserify
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70 Passport integration
71 Dependency injection
72 Beginner guide
73 Use cases for Node.js
74 Sequelize.js
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76 How modules are loaded
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79 Error managemtn
80 Node.js v6 new features
81 Eventloop
82 History of Node.js
83 passport.js
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90 Running node.js as a service
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96 Node.js localization
97 Deploying node.js applications without downtime
98 express.js with angular.js
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100 Creating library that supports promises and error-first callbacks
101 MSSQL integration
102 Project structure
103 Avoid callback hell
104 Arduino communication
105 N-API
106 Multi-threading
107 Windows authentication
108 Require
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110 Push notifications
111 Contributors