[expo-auth-session] Missing '/--/' on returnUrl

Summary

I’ve set up the basic things to have a working Google signin with expo auth session, defined the expo.originalFullName to at-myOrgName/myProjectName, the expo.scheme to my app name (it’s kind of a unique name, so we don’t have trouble about having another app with the same scheme installed). Native sign in just works, but with the expo go proxy it seems to be stuck at “ValidationError: “returnUrl” must be a valid url”. Then I had the brilliant idea of opening the thing in the browser de facto instead of just that internal browser, when I did it, I realized something about the following URL

https://auth.expo.io/at-myOrg/myProjectName/start?purposedlyOmittedByMe&returnUrl=exp%3A%2F%2F10.0.0.102%3A19000expo-auth-session

Note that the last query param returnUrl ends with ‘expo-auth-session’. Removing it, it shows me the correct screen, a “Yes” and “No” button, to proceed or cancel the flow. Also note that after the flow finished, I wasn’t redirected back to the app (I can’t really find fault about this point, since the flow should’ve worked in the ‘internal’ browser). It could be an error in my part, if so, I apologize about it beforehand. Following, we have the piece of code related

export const User: FC = observer(() => {
  const [isVisible, setIsVisible] = useState(false);
  const [request, response, promptAsync] = Google.useAuthRequest({
    expoClientId: process.env.GOOGLE_EXPO_CLIENT_ID,
    androidClientId: process.env.GOOGLE_ANDROID_CLIENT_ID,
  });
  const {
    constantStore: { colorMode },
    userStore: { getUser, uid, email, name, picture, setUser },
  } = useStores();

  useEffect(() => {
    if (response?.type === "success") {
      getUser(response.authentication.accessToken);
    }
  }, [response]);

  return (
    <>
      <Avatar />
      <Dialog>
        <Typography isTitle tx="modal-user.title" />
        {uid ? (
          <View>
            <Avatar />
            <Typography />
            <Typography />
            <Button />
          </View>
        ) : (
          <Button
            disabled={!request}
            icon="google"
            onPress={() => {
              promptAsync();
            }}
            style={{
              marginTop: Spacings["s4"],
            }}
            tx="modal-user.login-with-google"
          />
        )}
      </Dialog>
    </>
  );
});

I’ve also tried passing useProxy: true in promptAsync but faced the same thing. Again, this can be an error at my part. Thanks in advance

EDIT: after reading #16834 and #16852 we now know that the problem is a missing ‘/–/’ instead of appending ‘expo-auth-session’.

EDIT2: This seems to be related to the migration from expo linking, that changes makeUrl to createUrl. Don’t really know If this is the desired behavior now.

Managed or bare workflow? If you have ios/ or android/ directories in your project, the answer is bare!

managed

What platform(s) does this occur on?

Android

SDK Version (managed workflow only)

44

Environment

expo-env-info 1.0.2 environment info: System: OS: Linux 5.10 Manjaro Linux Shell: 5.8.1 - /usr/sbin/zsh Binaries: Node: 16.13.2 - /usr/sbin/node Yarn: 1.22.18 - /usr/sbin/yarn npm: 8.5.4 - /usr/sbin/npm npmPackages: expo: ~44.0.0 => 44.0.6 react: 17.0.1 => 17.0.1 react-dom: 17.0.1 => 17.0.1 react-native: 0.64.3 => 0.64.3 react-native-web: 0.17.1 => 0.17.1 npmGlobalPackages: eas-cli: 0.48.2 expo-cli: 5.3.0 Expo Workflow: managed

Note that I’m running in WSL2

Reproducible demo

Don’t know if the above should suffice, if not, let me know

[mzanini]

I have the exact same issue trying to make Google auth with Google.useAuthRequest with Expo Go in iOS simulator. Providing additional options to useAuthRequest does not change anything because in the expo go simulator environment they are not taken into account. Digging into the code, this is what I have found:

1. useProxy is always true at this line when in ExpoGo
2. since useProxy is true, when using promptAsync, the request uses the redirectUri created here
3. in getDefaultReturnUrl here, the urlPath argument is null and path is set to SESSION_PATH which is expo-auth-session (without any slashes).
4. As mentioned in the related issue, Linking.createUrl now receives a path argument that does not have a slash and creates the invalid return url that you (and I) have seen.

One way to “resolve” this is to pass to Linking.createUrl the option isTripleSlashed: true. Unfortunately that option is not passed down from Google.useAuthRequest so specifying isTripleSlashed there is not going to change anything.

For now I just changed the code in node_modules/expo-auth-session to set isTripleSlashed: true here and Google authentication works correctly.

Hope this gets fixed soon!

[pamojadev]

i’m using AuthSession.makeRedirectURI({useProxy : false, isTripleSlashed : true}) which allows the isTripleSlashed option but the url returned is not triple slashed