Google Cloud Functions enable CORS?

Solution 1:

here we go:

exports.helloWorld = function helloWorld(req, res) {  
  res.set('Access-Control-Allow-Origin', "*")
  res.set('Access-Control-Allow-Methods', 'GET, POST');

  if (req.method === "OPTIONS") {
    // stop preflight requests here
    res.status(204).send('');
    return;
  }

  // handle full requests
  res.status(200).send('weeee!);
};

then you can jquery/whatever it as usual:

$.get(myUrl, (r) => console.log(r))

Solution 2:

I'm the product manager for Google Cloud Functions. Thanks for your question, this has been a popular request.

We don't have anything to announce just yet, but we're aware of several enhancements that need to be made to the HTTP invocation capabilities of Cloud Functions and we'll be rolling out improvements to this and many other areas in future iterations.

UPDATE:

We've improved the way you deal with HTTP in Cloud Functions. You now have full access to the HTTP Request/Response objects so you can set the appropriate CORS headers and respond to pre-flight OPTIONS requests (https://cloud.google.com/functions/docs/writing/http)

Solution 3:

You can use the CORS express middleware.

package.json

npm install express --save
npm install cors --save

index.js

'use strict';

const functions = require('firebase-functions');
const express = require('express');
const cors = require('cors')({origin: true});
const app = express();

app.use(cors);
app.get('*', (req, res) => {
    res.send(`Hello, world`);
});

exports.hello = functions.https.onRequest(app);

Solution 4:

I've just created webfunc. It's a lightweight HTTP server that supports CORS as well as routing for Google Cloud Functions. Example:

const { serveHttp, app } = require('webfunc')

exports.yourapp = serveHttp([
  app.get('/', (req, res) => res.status(200).send('Hello World')),
  app.get('/users/{userId}', (req, res, params) => res.status(200).send(`Hello user ${params.userId}`)),
  app.get('/users/{userId}/document/{docName}', (req, res, params) => res.status(200).send(`Hello user ${params.userId}. I like your document ${params.docName}`)),
])

In your project's root, simply add a appconfig.json that looks like this:

{
  "headers": {
    "Access-Control-Allow-Methods": "GET, HEAD, OPTIONS, POST",
    "Access-Control-Allow-Headers": "Origin, X-Requested-With, Content-Type, Accept",
    "Access-Control-Allow-Origin": "*",
    "Access-Control-Max-Age": "1296000"
  }
}

Hope this helps.