Flow Control Patterns


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Flow Control Patterns

Mastering asynchronous flow control in Node

About the Book

In JavaScript, any operation involving the network or the file system is always asynchronous. Once you start implementing complex logic, coordinating I/O operations can become a challenge in Node. This book will give you basic patterns and tools that will allow you to master and control asynchronous flow in Node. It covers the standard Callback pattern, queues, Event Emitters and Streams.

About the Author

Pedro Teixeira
Pedro Teixeira

Geek, programmer, freelancer, and entrepreneur. Author of some Node.js modules, the Node Tuts screencast show, and the Hands-on Node.js e-book and overall fervent proclaimer of the Node.js creed.

Wrote a book for Wiley on Node.js.

Partner of YLD.

Organizer of the Lisbon JavaScript Conference.

Table of Contents

  • 1. The source code
  • 2. Introduction
  • 3. The Callback patterm
  • 4. Orchestrating callbacks
    • 4.1 Series
    • 4.2 Parallel
    • 4.3 Waterfall
    • 4.4 Collections
      • 4.4.1 Parallel iteration
      • 4.4.2 Parallel, but with limit
  • 5. Using a work queue
  • 6. Using an event emitter
    • 6.1 Consuming events
    • 6.2 Producing events
      • 6.2.1 How event emitter handles errors
    • 6.3 Listening to events once
    • 6.4 Synchronous event delivery
    • 6.5 Event delivery exceptions
  • 7. Streams
    • 7.1 Readable stream
      • 7.1.1 Creating a readable stream
      • 7.1.2 Pull stream vs. push stream
    • 7.2 Writable streams
    • 7.3 Connecting streams using pipe
    • 7.4 Flow control in streams
    • 7.5 Transform streams
  • 8. Pipe specialisation via feature detection
    • 8.1 Analysing Mikeal/request
      • 8.1.1 Wrapping .pipe()
  • 9. Summary

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