Master asynchronous calls and write programs that do what you intended
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...
You know how frustrating it is to try to make your Node program do what you want. The code you’ve written has no syntax errors, but running it has strange behavior like:
You’re supposed to “think asynchronously” when programming in Node but it’s not exactly clear how to accomplish this. Examples in tutorials seem reasonable when reading them but translating them into your situation is difficult. You don't know which statement to write next.
Trying to find the official word on this leaves you dumbfounded. How come the official docs at nodejs.org have no word on how you’re supposed to program Node?
It looks like the real information is scattered across blogs, Github issues and Stack Overflow answers. Going that route takes forever - and you don’t which pieces would be the best use of your time.
What if you were able to take the vision in your head and turn it into a working and running program. Imagine knowing exactly which statement to write next. You’d be the one in control of your app. You’d write programs that
It’s true asynchronous calls are a little hard to grasp, but it’s possible to make your text editor the place where working programs are written.
The key to writing working programs is to understand how Node executes your calls. The internals of Node are predictable when you zoom out from the level of individual statements and for-loops. When you look at the system that takes over when you return from a top-level function you’ll start to understand how Node works.
When you understand what takes place behind the scenes, you're able to get the right mental model how to write Node programs. You'll be able to write programs that work as intended.
And that is exactly what you’ll learn in this book.
When you grab this book, you’ll learn:
The book is written in a concise form that is perfect for busy people who don’t have too much spare time on their hands.
Theory alone is not enough if you don’t get to practice your newly learned skills. You’ll write five programs as exercise assignments. You get to build a news aggregator and a Twitter bot, call weather APIs and calculate cryptographic hash functions.
Breathing Relaxation Method
Fix Broken Code
File Hasher
Twitter Weather Bot
News Aggregator
Excercise: Breathing Relaxation Method
Excercise: Fix Broken Code
Excercise: File Hasher
Excercise: Twitter Weather Bot
Excercise: News Aggregator
You should know entry level JavaScript and have some previous experience in programming. In terms of Node, you don't need in-depth experience with Node. All advanced Node topics are introduced with links to additional material.
No. This book is for learning asynchronous calls or the operating principles at the heart of Node. The book uses callbacks and plain Node. Learning Promises and async/await is recommended after reading this book and is much easier when you've got the right mental model for Node.