Using two await in an async function

Question

I am trying to return a value from two async functions. I am trying the method used in this thread. Using await outside of an async function

However, I am always getting an undefined value.

common.loggedInUserisAdmin().then((currentUser) => {
   console.log(currentUser); // This line is executed before values return from loggedInUserisAdmin function.
});

// Here is my async functions code.
async loggedInUserisAdmin() {
  (async () => {
    await 
       this.getCurrentAccount().then().then((currentUser) => {
         this.getUserDetailsByEmail(currentUser.userName).then((userData) => {
          return userData.admin;
      })
   })
 })();
},

async getCurrentAccount() {
    return await msalApp.getAccount();
},

async getUserDetailsByEmail() {
    const dataUrl = `$https://localhost:12345/User/GetUserDetails?emailAddress=${emailAddress}`
    const errorMessage = 'Error getting current user'
    return await authorisedFetch(dataUrl, errorMessage)
}

score 1 · Accepted Answer · answered Jul 24 '20 at 13:24

I see following problems in your code:

You have mixed up async-await syntax with promise chaining.
Value returned from a callback function isn't the return value of the outer loggedInUserisAdmin method.
Also not sure what is the purpose of having an async IIFE inside an async method.

Your loggedInUserisAdmin method can be simplified as shown below:

async loggedInUserisAdmin() {
  const currentUser = await this.getCurrentAccount();
  const userData = await this.getUserDetailsByEmail(currentUser.userName);

  return userData.admin;
}

Make sure that code that calls this method has a catch block to catch and handle any errors that might occur during the execution of this method.

score 0 · Answer 2 · answered Mar 17 '22 at 19:50

After looking your code, it was easy identifying mistakes on mixing promises/async/await/then etc. In fact, the code is easier to solve than you think. In Promise.then((value) => {} ) you must keep chaining functions , but with await you will receive a value as result, and you have to store the result in a variable or constant. await turns your code sequential, instead of chaining functions on and on when using Promises. Take a look at the fixed code below:


async loggedInUserisAdmin() {
   const currentUser = await this.getCurrentAccount();
   const userData = await this.getUserDetailsByEmail(currentUser.userName)
   return userData.admin
}

Behind the scenes, node compiler/interpreter is doing magic with state machines and several management in order to turn possible our code be simple. Making our lives easier.

Using two await in an async function

2 Answers2