大量异步并发请求控制并发解决方案

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实现思路:

可以使用 Promise 和异步函数。手动实现一个同步队列

测试数据

const tasks = new Array(88).fill(0).map((_, i) => () => {
  return new Promise((resolve) => {
    setTimeout(() => {
      resolve(i)
    }, Math.random() * 1000)
  })
})

核心代码

function limitRequest(tasks, limit) {
  const queue = []
  let runingCount = 0
  function enqueque(task) {
    return new Promise((resolve, reject) => {
      queue.push({
        task,
        resolve,
        reject,
      })
      run()
    })
  }

  function run() {
    while (queue.length > 0 && runingCount < limit) {
      runingCount++
      const { task, resolve, reject } = queue.shift()
      task()
        .then((value) => {resolve(value);console.log(value)})
        .catch((err) => reject(err))
        .finally(() => {
          runingCount--
          run()
        })
    }
  }

  return Promise.all(tasks.map((task) => enqueque(task)))
}

测试代码

console.log(await limitRequest(tasks, 10))