Asynchronous Programming Patterns in Javascript: How to Use Async/Await and Promises to Solve Programming Problems

Introduction
	Structure
Getting started with async/await
	Async functions
		How to use the Promise
		The benefits of Promises
		The await keyword
		Async function examples
		Chaining Promises
	Promises
		Callbacks
		The Promise constructor
		Promise states
		Result value
	Error handling
		Error callback in the Promise constructor
			Rejecting a Promise
			Detecting errors
		Error propagation in Promise chains
Parallel and sequential processing
	Parallel processing with Promise.all
		Results
		Errors in Promise.all
	Early init
Returning multiple values
Convert between Promises and callbacks
	Callback styles
		Node-style callbacks
	Convert callbacks to Promises
		Promise constructor
			Promisified functions
		util.promisify
		Usual problems
			Handle this
			function.length
	Convert Promises to callbacks
Promise timeouts
	Promise.race
	Timeout implementation
		Clear timeout
		Error object
The async serializer pattern
	Why await is not a solution
	A general-purpose solution
The async disposer pattern
	Disposer pattern
Retrying async operations
	Backoff algorithm
		Exponential backoff
	Javascript implementation
		Rejection-based retrying
		Progress-based retrying
Paginating with async generators
	Pagination
	A solution with async generators
		Breaking it down
	Making it generic
Using async functions with postMessage
	Request-response communication
		Response identification
			MessageChannel
		Error handling
	Using Promises
Collection processing with async functions
	Async for iteration
	Async functions with reduce
		Asynchronous reduce
		Timing
			await memo last
			await memo first
			When parallelism matters
	Async functions with map
		Concurrency
			Batch processing
			Parallel processing
			Sequential processing
	Async functions with forEach
		Controlling the timing
			Waiting for finish
			Sequential processing
	Async functions with filter
		Async filter with map
			Concurrency
		Async filter with reduce
			Sequential processing
	Async functions with some/every
		Using an async filter
			Short-circuiting
		Async some
		Async every
		Parallel processing
Common errors
	Not propagating errors
	Missing await in try..catch
	Not checking the return value
	Not closing resources in case of a rejection
	Using both the rejection and resolve handlers in one then function
	Not waiting for an async forEach
Glossary
About the author