Using Firebase Cloud Functions to fetch data from an external API (Timeout) - node.js

Question

This is my code:
const functions = require('firebase-functions');
const axios = require('axios');
const cors = require('cors')({ origin: true });
exports.apistatus = functions
.region('europe-west1')
.https.onRequest((req, res) => {
cors(req, res, () => {
if (req.method !== "GET") {
return res.status(401).json({
message: "Not allowed"
});
}
return axios.get('https://api.bsmsa.eu/ext/api/bsm/gbfs/v2/en/station_status')
.then(response => {
console.log(response.data);
return res.status(200).json(
response.data
)
})
.catch(err => {
return res.status(500).json({
error: err
})
})
})
// ! res.end();
});
I'm already using the Blaze Plan but I always get this when I invoke it >> Function execution took 60002 ms, finished with status: 'timeout'.
If I try to terminate the function like the documentation says with res.send() or res.end() I get this error: Error: Can't set headers after they are sent.
It works fine when I try to fetch other APIs.

Answer 1

You need a return keyword before the cors() function call.
exports.apistatus = functions
.region('europe-west1')
.https.onRequest((req, res) => {
return cors(req, res, () => { // <------ RETURN NEEDED HERE
if (req.method !== "GET") {
return res.status(401).json({
message: "Not allowed"
});
}
return axios.get('https://api.bsmsa.eu/ext/api/bsm/gbfs/v2/en/station_status')
.then(response => {
console.log(response.data);
return res.status(200).json(
response.data
)
})
.catch(err => {
return res.status(500).json({
error: err
})
})
})
});
Your axios code is being executed, and I suspect it's receiving a response, but because you aren't returning the result from CORS, the "parent" cloud function never knows the task has finished.
This example shows a sample from the official Firebase GitHub where they're using Cors.