正在编写 async/await 版本的回调

Question

我正在尝试将 callback 重写为 async/await，但以下代码不起作用，导致注释行的 CPU 偏高。

const kurento = require('kurento-client')

function getKurentoClient (kmsUrl) {
  return new Promise((resolve, reject) => {
    kurento(kmsUrl, (error, kurentoClient) => {
      if (error) {
        return reject(error)
      } else {
        return resolve(kurentoClient) // never returns
      }
    })
  })
}

async function test () {
  let result = await getKurentoClient('ws://localhost:8888/kurento')
  console.log('done')
}

test()

Answer 1

来自mozilla.org website：

The Promise.resolve(value) method returns a Promise object that is resolved with the given value. If the value is a thenable (i.e. has a "then" method), the returned promise will "follow" that thenable, adopting its eventual state; if the value was a promise, that object becomes the result of the call to Promise.resolve; otherwise the returned promise will be fulfilled with the value.

来自 bluebird GitHub:

when promises resolve other promises or things with then(aka thenables, like _kurentoClient in this case) - they have to wait for it to call then itself.

如您所料，kurento 客户端有一个 then 函数（thenable 也是如此），因此 Promise 正在尝试解决它。由于错误（或不是错误。老实说，我还没有进行足够的研究来确定）它会永远解决自己。

据我所知，似乎 this kurento commit 试图修复它，解析为 "untheanble"。我看到提交来自 31 Oct 2016 但最新版本来自 Sep 2016 所以我认为未部署固定版本。

正在编写 async/await 版本的回调

Writing async/await version of a callback

node.js

async-await

kurento