JavaScript Async Programming Patterns

Async Programming Basics

JavaScript is single-threaded, making async programming essential for handling I/O operations. From callbacks to Promises to async/await, the evolution has improved code readability.

Promise Basics

const results = await Promise.all([
  fetch('/api/users'),
  fetch('/api/posts')
])

const fastest = await Promise.race([
  fetch('/api/server1'),
  fetch('/api/server2')
])

async/await Best Practices

async function getData() {
  try {
    const data = await fetchData()
    return data
  } catch (error) {
    console.error(error)
    throw error
  }
}

Common Pitfalls

• Missing await on Promises
• Serial operations that could be parallel
• Incomplete error handling