async/await-5. Correctly handle multiple await operations

const fetch = require('node-fetch')

const sleep = (timeout = 2000) => new Promise(resolve => {
  setTimeout(resolve, timeout)
})

async function getZhihuColumn(id) {
  await sleep(2000)
  const url = `https://zhuanlan.zhihu.com/api/columns/${id}`
  const response = await fetch(url)
  return await response.json()
}

1. Two requests serially process multiple await operations, call the asynchronous operation first, and then process the asynchronous result

const showColumnInfo = async (id) => {
  console.time('showColumnInfo')
  const qianduanzhidian = await getZhihuColumn('qianduanzhidian')
  const FrontendMagazine = await getZhihuColumn('FrontendMagazine')
  console.log(`name:${qianduanzhidian.name}`)
  console.log(`description:${qianduanzhidian.description}`)
  console.log(`name:${FrontendMagazine.name}`)
  console.log(`description:${FrontendMagazine.description}`)
  console.timeEnd('showColumnInfo') // 4349.122ms
}
showColumnInfo()

2. Two requests are parallel

const showColumnInfo = async (id) => {
  console.time('showColumnInfo')
  const qianduanzhidianPromise = getZhihuColumn('qianduanzhidian')
  const FrontendMagazinePromise = getZhihuColumn('FrontendMagazine')

  const qianduanzhidian = await qianduanzhidianPromise
  const FrontendMagazine = await FrontendMagazinePromise
  console.log(`name:${qianduanzhidian.name}`)
  console.log(`description:${qianduanzhidian.description}`)
  console.log(`name:${FrontendMagazine.name}`)
  console.log(`description:${FrontendMagazine.description}`)
  console.timeEnd('showColumnInfo') // 2526.615ms
}
showColumnInfo()

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