Get request data from a promise (RIOT API)

Question

I have a request made with "request" from NodeJs, and I want to get the data with a promise. All good because the console shows me the information that I am requested. The problem is when I call the promise function, and the console shows me this. How can I get the real value?

let leagueTier = (accId) => new Promise(async (resolve, reject) => {
            request({
                url: `https://${reg}.api.riotgames.com/lol/league/v4/entries/by-summoner/${accId}${key}`,
                json: true
            }, (error, response, body) => {
                if (!error && response.statusCode === 200) {
                    resolve(body[0].tier.toLowerCase())
                } else {
                    reject(Error('It broke'))
                }
            })
        }).then(function(res) {
            return res;
        })

This is where I call the function

.attachFiles([`./images/${leagueTier(body.id)}.png`])

(node:5868) UnhandledPromiseRejectionWarning: Error: ENOENT: no such file or directory, stat 'D:\Dev\shen-bot\images[object Promise].png'

How can I access the string of the request I made? Maybe I shouldn't use promises?

Answer 1

The leagueTier return value will be a promise that eventually resolves or rejects into a value. You can't simply add the return value as part of a string. You can either use await or then to wait for the value to come through.

// asuming you are in async function context
.attachFiles([`./images/${await leagueTier(body.id)}.png`]);

// or
leagueTier(body.id).then(tier => {
  .attachFiles([`./images/${tier}.png`]);
});

---

Note that your current code:

.then(function(res) {
  return res;
})

Does absolutely nothing and can be omitted.