UnhandledPromiseRejectionWarning，但我正在处理错误？

Question

I'm getting the following error:

Houston we got an err at getGames in index.js
(node:72197) UnhandledPromiseRejectionWarning: #<Object>
(node:72197) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 2)
(node:72197) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
error at getGames rp

Here is the relevant code:

Helper function to get Data from API (rp is request-promise-native)

const getGames = async () => {
   return await rp(`https://api.steampowered.com/IDOTA2Match_570/GetTopLiveGame/v1?key=${KEY}&partner=0`)
   .catch(err => console.log('error at getGames rp'))
   .error(err => console.log('actual error at getGames rp'))
}

I call this every 5 seconds

app.get('/api/update', async (req, res) => {
  const data = await getGames()
  .catch(err => console.log('Houston we got an err at getGames in index.js'))
  const dataJson = JSONbig.parse(data);

  if (dataJson.game_list && dataJson.game_list.length) {
    for (let i = 0; i < dataJson.game_list.length; i++) {
      const game = dataJson.game_list[i];
...

The '/api/update' endpoint gets called every 5 seconds. I get the above error. My for loop stops iterating. I'd like it to skip the one it's error'ing on, but it's saying im not handling the error. I have catch blocks and even error blocks and I can't seem to figure out why this is happening.

I've also tried manually calling:

`https://api.steampowered.com/IDOTA2Match_570/GetTopLiveGame/v1?key=${KEY}&partner=0`

in postman many times in quick succession, but postman never errors out. So the issue is in my code somewhere. I've handled all errors so I can't seem to find what i'm not handling.

Answer 1

There are a few issues:

• Only catch at a point where you can actually handle the error. Here, you probably only want to catch in the .get callback (otherwise, if you .catch in getGames , you'll return a resolved Promise, not a rejected Promise)

• When an error occurs, don't try to parse the data (since it won't be populated) - trying to parse and iterate over it will result in more errors

• There's no point in having an async function that only has one await that immediately gets returned

const getGames = () => {
  return rp(`https://api.steampowered.com/IDOTA2Match_570/GetTopLiveGame/v1?key=${KEY}&partner=0`);
};

app.get('/api/update', async (req, res) => {
  const data = await getGames()
    .catch(err => {
      console.log('Houston we got an err at getGames in index.js');
      // handle error
    });
  if (!data) {
    // There was an error
    return;
  }
  const dataJson = JSONbig.parse(data);
  // rest of the code
});