How to return value from async-await function?-CodePudding

I would like to return user's phone number but what I got is [object Object]. Im thinking if it return the value before await is done.Here is my code.

//assume phone number is 12345678

async function user_attr() {
    try{
    const { attributes } = await Auth.currentAuthenticatedUser();
    console.log(JSON.stringify(attributes.phone_number)); //output:12345678
    return (JSON.stringify((attributes.phone_number)))
    } catch (e) {
        console.log(e);
    }
}

console.log('return=' user_attr()) //output: return=[object Object]

console.log('return=' JSON.stringify(user_attr())) //output: return={"_U":0,"_V":0,"_W":null,"_X":null}

To output 12345678 so that i can access it outside async function.

CodePudding user response：

You need to await the calling function as well. Async function always return Promise that are needed to await.

async function getPhoneNumber() {
  const phone = await user_attr();

  console.log('return=' phone)
}

getPhoneNumber();

CodePudding user response：

YOu are returning a promise hence you need to do

  const checkFunction = async() => {
const promiseRes = await user_attr()
    
    console.log('return=' promiseRes ) 
    
    console.log('return=' JSON.stringify(promiseRes)) //output: ret
    }

Hope it helps

CodePudding user response：

async function user_attr() {
    try {
        const { attributes } = await Auth.currentAuthenticatedUser();
        //It is similar to "return new Promise(function (resolve) { resolve(attributes.phone_number) });"
        return attributes.phone_number;
    } catch (error) {
        console.log(error);
    }

}

//then((phone_number) => console.log("return="   phone_number))

user_attr().then(function (phone_number) {
    console.log("return="   phone_number);
})

//or async await

async function log_user_attr_phone_number() {
    const phone_number = await user_attr();
    console.log("return="   phone_number);
}

log_user_attr_phone_number();

async function docs