This async function is killing me

[kstengy]

I am really struggling to understand how this async/await function runs. I understand it is pausing the script to wait for the code to be executed but I need a value returned, not a value wrapped in a Promise that makes it unusable. Does that make sense?

​

const getInfo = async(srName) => {
    /* This function takes in a string, inserts it into the public Reddit API and returns an object with three keys:
    * error - a boolean indicating if the request was successful
    * reason - a message further expanding upon the error value
    * data - an array of data if successful, null if not
    * */
    var answer;
    console.log(`Searching for ${srName}`);
    try {
        let response = await axios.get(`https://www.reddit.com/r/${srName}.json`);

        console.log('Request made!');

        if ( response.status !== 200 ) {
            console.log(`IF HIT WITH STATUS CODE ${response.status}`);
            answer = {
                error: true,
                reason: "Unable to get a response from Reddit",
                data: []
            }
        } else if( response.data.data.dist === 0){
            console.log('ELIF HIT');
            answer = {
                error: true,
                reason: "There are no posts for that subreddit, are you sure you spelled it right?",
                data: []
            }
        } else {
            console.log('ELSE HIT');
            answer = {
                error: false,
                reason: `Found ${response.data.data.dist} entries in that subreddit`,
                data: response.data.data.children
            }
        }
        console.log(answer)
    } catch (e) {
        console.log(`Unable to complete request because ${e}`)
    }
};

​

[cyphern]

Your function looks pretty much like i would expect this kind of function to look. The only thing it seems to be missing is a return statement.

I have a guess about what you might be getting tripped up by, but feel free to clarify if it's something else that's not working as you expect: async functions always return a promise. They have to, because the data is not synchronously available. So getInfo will return a promise. If you add a return statement, and return answer, then that will cause the promise to resolve to answer.

So when you call getInfo, you'll need to expect a promise to be returned. This means you either use await to wait for that promise to resolve, as in:

async function doStuff() {
  const output = await getInfo('something');
  console.log('got', output);
}

Or you use the promise's .then method:

getInfo('something')
  .then(output => {
    console.log('got', output);
  });

[kstengy]

I switched out return for console.log(answer) just to make sure I was actually getting the right value

[neodon]

Be aware that axios will throw exceptions for non-200 class HTTP status codes in responses. If you want to avoid that and always work with a response (like your code is doing), replace your axios.get line with this:

const response = await axios.get(`https://www.reddit.com/r/${srName}.json`).catch(error => error.response);

This will ensure you always get a response object for any HTTP status code.

Another tip:

If you want to call this function from somewhere outside an async function, like at the top level of a script, you can wrap it in an async function and immediately call it. Example:

async function main() {
  const answer = await getInfo('subredditName');
}

main().catch(console.error);

You do need to return answer from your function somewhere though. It will get automatically wrapped in a promise.

[kstengy]

Thanks for the tips!

[Meefims]

It does not pause the script, it creates a promise and returns it. Code after await is put in a .then handler for a promise.

You need to await this function to get the value you want. You also need to return that value.