promise.then() not working when I send in another promise into it

Question

I have 2 function getAccountInfo() and getAdjustmentsInfo(accountInfo) they both return a new promise. The only different is that the second function needs the information returned from the first function.

I tried to declare these 2 function first, and call them one by one using then(). But it is not working as I expected.

These are the functions, as you can see the second function needs account_code from the first accountInfo object:

function getAccountInfo() {
    return new Promise((resolve, reject) => {
        getAccountCallbackFunc((errResponse, response) => {
            if (errResponse) {
                return reject(errResponse);
            }
            resolve(response);
        });
    });
}

function getAdjustmentsInfo(accountInfo) {
    return new Promise((resolve, reject) => {
        getAdjustmentCallbackFunc(accountInfo[0].account_code, function (errResponse, response) {
            if (errResponse) {
                reject(errResponse);
            }
            if (response) {
                resolve(response);
            }
        });
    });
}

This is the controller code to call the functions:

var accountInfo = {};

getAccountInfo()
    .then(response => {
        accountInfo = response.data.accounts.account;
        console.log(accountInfo);
    })
    .then(getAdjustmentsInfo(accountInfo))
    .catch(err => console.log(err));

So I run the getAccountInfo() function first and run the first then() to saved the account information to the external variable accountInfo. Next I run the second then() trying to pass the accountInfo to the second function, which is not working, the second function never got called. Is that something I am missing? Please let me know.

Answer 1

There are couple of mistakes in your code. First is that you are not returning anything nor resolving any promise in the line accountInfo = response.data.accounts.account;console.log(accountInfo); so the .then(getAdjustmentsInfo(accountInfo)) will not be called. Secondly, i suppose the first argument to a .then() is always a callback with the first argument being something that is returned from the previous Promise.

Your function getAccountInfo() returns a promise. When that promise is resolved you can directly use that as follows.

var accountInfo = {};

getAccountInfo()
     .then(response => {
          accountInfo = response.data.accounts.account;
          console.log(accountInfo);
          getAdjustmentsInfo(accountInfo)
      })
     .then(resultFromPreviousPromise => {
       //Use the resultFromPreviousPromise if wanted else you can skip this .then()
      })
     .catch(err => console.log(err));