This dependency supposedly supports web, but the implementation to listen for the callback and retrieve the token is missing. After digging around for the last three days, a few people suggested that it would work using the dart:html library, with onMessage, and postMessage functions.
Here's my setup:
import 'dart:html' as html;
import 'package:http/http.dart' as http;
import 'package:flutter/material.dart';
import 'package:oauth2/oauth2.dart' as oauth2;
import 'package:url_launcher/url_launcher.dart';
class AuthYoutube {
var httpClient = http.Client();
Future<oauth2.Client> getClient() async {
var grant = new oauth2.AuthorizationCodeGrant(
CLIENT_ID, AUTH_DOMAIN, AUTH_TOKEN,
secret: secret);
var authorizationUrl =
grant.getAuthorizationUrl(REDIRECT_URI, scopes: scopes);
html.window.open(authorizationUrl.toString(), "open");
Completer<LinkedHashMap<dynamic, dynamic>> completer = Completer();
html.window.onMessage.listen((event) async {
completer.complete(event.data as LinkedHashMap<dynamic, dynamic>);
});
Uri responseUri;
completer.future.then((value) {
responseUri = Uri.parse(value.toString());
return grant.handleAuthorizationResponse(responseUri.queryParameters);
});
}
} And the separate route set as the callback URL:
class Special extends StatelessWidget {
static String route = "/special";
@override
Widget build(BuildContext context) {
final loc = Uri.parse(html.window.location.href);
final code = loc.queryParameters["code"];
print("code $code");
html.window.postMessage(code, html.window.location.origin);
return Text("All done");
}
}
What ends up happening is the auth token shows up in the address bar at the last step. I can see it in there after ?code=, but it doesn't get printed out. The listen method gets triggered 5-6 times throughout the entire flow (while clicking on "allow" in the other window). In the console, I only get this one error:
Uncaught (in promise) Error: Bad state: Future already completed
at Object.throw_ [as throw] (errors.dart:212)
at _AsyncCompleter.new.complete (future_impl.dart:43)
at authYT.dart:41
at Generator.next (<anonymous>)
at runBody (async_patch.dart:84)
at Object._async [as async] (async_patch.dart:123)
at authYT.dart:40
at Object._checkAndCall (operations.dart:324)
at Object.dcall (operations.dart:329)
at html_dart2js.dart:37246
