异步/等待，“未解析的变量或类型等待”

Question

    let usersInAuth0 = [];    
    for (let i = 0; i < 5; i++) {
      const usersInAuth0InPage = await getUsersFromAuth0(i); // error in WebStorm
      if (_.isEmpty(usersInAuth0InPage)){
        return res.status(200).send(usersInAuth0);
      } else {
        usersInAuth0.push(usersInAuth0InPage);
      }
    }

    const getUsersFromAuth0 = async (page) => {
      return await management.getUsers({per_page:100, page: page})
    }

Trying to use async/await. From the auth0 management API you can only get 100 user per page so I'm making several request until I have all users.

WebStorm gives the warning (on line 3): "unresolved variable or type await".

How am I suppose to use async/await in this situation?

Answer 1

In order to use await , the function it's inside needs to be async . For example:

(async () => {
  let usersInAuth0 = [];    
  for (let i = 0; i < 5; i++) {
    const usersInAuth0InPage = await getUsersFromAuth0(i); // error in webstorm
    if (_.isEmpty(usersInAuth0InPage)){
      return res.status(200).send(usersInAuth0);
    } else {
      usersInAuth0.push(usersInAuth0InPage);
    }
  }

  const getUsersFromAuth0 = page => management.getUsers({per_page:100, page: page});
})();

https://codereviewvideos.com/blog/unresolved-variable-type-await/

Note that since management.getUsers returns a Promise, you don't need to make getUsersFromAuth0 async - just return the promise and await its resolution higher up.

Because async functions return promises, you'll need to make sure that whatever consumes this whole code block is able to handle the its return value being a promise. (your return res.status(200).send(usersInAuth0); won't actually return that value - the function will return a promise that resolves to that value, should the conditional it's inside be fulfilled)