Can't connect to localhost from Chrome extension

Question

I am working on a Chrome extension that tracks time, and uses Google App Engine for the backend.

For testing, I'm trying to connect a local version of the extension to a local version of the App Engine app. When I try to send a POST request, I'm getting:

XMLHttpRequest cannot load http://localhost:8080/report. Origin chrome-extension://mbndmimplohfkkcincjodnfpaapbbmei is not allowed by Access-Control-Allow-Origin.

But it works when I change the URL so that it posts to the appspot.com URL.

What is the Access-Control-Allow-Origin, and why is it stopping me from getting results from localhost?

Answer 1

I believe this is because you cannot make calls to a server that is not included in the permissions section of your manifest. The permissions section of manifest.json should look something like this:

"permissions": [     "http://myapp.appspot.com/*",     "http://localhost/*" ] 

Note, I haven't tested this, but it sounds like that is where your problem is coming from.

Answer 2

You can use custom ports.

manifest.json

"permissions": ["http://localhost/*"] 

background.js (using jQuery)

$.post('http://localhost:5000/some-endpoint');