Authenticating with GitHub

[alizahid]

Here's my config

{
  serviceConfiguration: {
    authorizationEndpoint: 'https://github.com/login/oauth/authorize',
    tokenEndpoint: 'https://github.com/login/oauth/access_token'
  },
  clientId: '',
  clientSecret: '',
  redirectUrl: 'github://oauth',
  scopes: ['gist']
}

When I call authorize, the GitHub login page opens, and once I click Authorize, it comes back to the app, and throws the following error

The operation couldn’t be completed. (org.openid.appauth.general error -7.)

<unknown>
    NativeModules.js:80:32
MessageQueue.__invokeCallback
    MessageQueue.js:400:4
<unknown>
    MessageQueue.js:139:11
MessageQueue.__guardSafe
    MessageQueue.js:316:6
MessageQueue.invokeCallbackAndReturnFlushedQueue
    MessageQueue.js:138:9
<unknown>
    debuggerWorker.js:72:58

What does that error mean? Doesn't give me much to go on.

Is it a config issue? Or something to do with redirectUrl?

[alizahid]

Another observation: Even if I press cancel on the dialog that shows up asking to continue or cancel when I call authorize, it throws the same error. Except it's error -3.

[alizahid]

After further debugging, turns out GitHub doesn't send the response in JSON by default. Which is what's throwing off AppAuth. How do I pass the Accept header with application/json to make sure it sends back appropriate response?

[jevakallio]

@alizahid can you point out to documentation/issues/resources that describes how the GitHub API behaves? Sounds really weird that they would not respond with a JSON payload - what do they send instead?

Also, can you please confirm that you're using react-native-app-auth version 2.2.0 or newer? The support for serviceConfiguration just landed yesterday afternoon, 4 hours before you created this issue, so if you had installed this before that, you might not be on the latest.

[alizahid]

Here's the documentation link for GitHub OAuth https://developer.github.com/apps/building-oauth-apps/authorization-options-for-oauth-apps/#response

By default, they send this

access_token=12123123&token_type=bearer

I modified some code in AppAuth-iOS, so it sends the Accept header with application/json, and I was able to move past the JSON parse error. But it seems that GitHub doesn't expire tokens, and thus, didn't send a expires_at value in the payload, which threw another exception. Something about NSDate can't parse from nil or something. I can't remember the exact exception.

I am on 2.2.1. You're correct, when I created this issue, 2.2.0 hadn't landed yet. But the documentation was updated. So my first issue was that it kept asking for issuer, and then I saw the update, so I updated.

[kadikraman]

@alizahid great investigation 🤓

You're right on both accounts. I've made a PR to fix the Android date parsing - #61

Looks like the Android library sets an accept header which is why it works following the date parsing fix, however iOS does not. They've actually included a comment to say they've set the header due to GitHub defaulting to sending the response in xml 😄

So we'll just need to do a PR to AppAuth-iOS to add it there as well.

[alizahid]

I've tested only with iOS, though.

Interesting that they have the GitHub behavior for Android, but not iOS. And I didn't see any mention of XML in GitHub documentation.

I've been looking into an alternative solution with WebView and fetch. But will switch back as soon as the PRs are merged. Thanks!

[kadikraman]

Ah yes, iOS had the same date formatting issue. I'd actually fixed it locally, but forgot to make a PR 🙈 - will do so now.

[jevakallio]

Just dropping a link to the AppAuth-iOS PR so it's easier to track when it's merged openid/AppAuth-iOS#206

[kadikraman]

Sorry to announce that this will be a won't-fix for us for iOS.

The AppAuth-iOS maintainers will not include the Accept header, because although it does not change the behaviour of other providers, it is not strictly in the OAuth spec so could be a slippery slope. Can't argue with that.

They do plan to extend the library to potentially enable setting custom headers, but these things take time, so I wouldn't hold my breath.

As suggested in the PR, a potential workaround would be to use a fork of the library that adds the header. (Or get GitHub to change their non-OAuth compliant ways - ha!) But realistically, we just won't be able to support GitHub login on iOS until further notice.

Read the discussion on the PR for more details: openid/AppAuth-iOS#206