Book Image

Mastering Node.js

By : Sandro Pasquali
Book Image

Mastering Node.js

By: Sandro Pasquali

Overview of this book

Node.js is a modern development stack focused on providing an easy way to build scalable network software. Backed by a growing number of large companies and a rapidly increasing developer base, Node is revolutionizing the way that software is being built today. Powered by Google's V8 engine and built out of C++ modules, this is a JavaScript environment for the enterprise.Mastering Node.js will take the reader deep into this exciting development environment. Beginning with a comprehensive breakdown of its innovative non-blocking evented design, Node's structure is explained in detail, laying out how its blazingly fast I/O performance simplifies the creation of fast servers, scalable architectures, and responsive web applications.Mastering Node.js takes you through a concise yet thorough tour of Node's innovative evented non-blocking design, showing you how to build professional applications with the help of detailed examples.Learn how to integrate your applications with Facebook and Twitter, Amazon and Google, creating social apps and programs reaching thousands of collaborators on the cloud. See how the Express and Path frameworks make the creation of professional web applications painless. Set up one, two, or an entire server cluster with just a few lines of code, ready to scale as soon as you're ready to launch. Move data seamlessly between databases and file systems, between clients, and across network protocols, using a beautifully designed, consistent, and predictable set of tools.Mastering Node.js contains all of the examples and explanations you'll need to build applications in a short amount of time and at a low cost, running on a scale and speed that would have been nearly impossible just a few years ago.
Table of Contents (20 chapters)
Mastering Node.js
About the Author
About the Reviewers

Bridging the client/server divide

Node is designed for high-concurrency environments, where many clients connecting simultaneously can have their needs met quickly and predictably. This ability also implies that each client can expect a Node server to respond rapidly when it itself sends many simultaneous requests.

One of Path's key design beliefs is that keeping state synchronized across clients and servers is complex and difficult to do well. For this reason, applications built with Path exchange data between clients and servers exclusively through the WebSockets protocol.

The following is a high-level view of how Path handles client requests. We see how the cluster module is used to share responsibility for handling socket connections among several socket servers:

Once a request has been assigned to a server that request must be fulfilled. We will call that a transaction. Each transaction is being fulfilled for a single user and, as such, fulfillment is delegated to a user object. This user object is a state machine, containing any specific state information for this user. Depending on transaction fulfillment requirements, one or more actors will be assigned, emitting their results (or error warnings). Authenticated users will have a unique machine to process their requests, while other users will share a common "guest" machine.

In this way each request can be framed within a user scope, accurately resolved within the canonical state and responded to with confidence.