WASM raises `UnimplementedError`

[Ali-Toosi]

Hello team,

Thanks for fixing #145 so quickly. I can confirm the project builds now, but it still doesn't run in WebAssembly (raises UnimplementedError right at the subscription point).

I've had a look around, and I think there are a couple of places that are using the deprecated dart:html: one and two

I believe this is why WASM raises the error (or at least one reason). It would be great if they could be replaced with package:web. More information here and here.

Here's a minimal Flutter app that reproduces the issue (make sure to run with WASM: flutter run -d chrome --wasm):

import 'package:flutter/material.dart';
import 'package:pubnub/pubnub.dart';

void main() {
  runApp(const MainApp());
}

class MainApp extends StatefulWidget {
  const MainApp({super.key});

  @override
  State<MainApp> createState() => _MainAppState();
}

class _MainAppState extends State<MainApp> {
  late final PubNub pubnub;
  late final Subscription subscription;
  String latestMessage = 'No Message Yet';

  @override
  void initState() {
    super.initState();
    pubnub = PubNub(
      defaultKeyset: Keyset(subscribeKey: 'sub-c-XXXXXXXX', userId: UserId('demo')),
    );
    subscription = pubnub.subscribe(channels: {'channel-test'});
    subscription.messages.listen(
      (e) {
        // Handle incoming messages
        print("MESSAGE RECEIVED: ${e.payload}");
        setState(() {
          latestMessage = e.payload.toString();
        });
      },
      onError: (e) async {
        print("ERROR: $e");
        setState(() {
          latestMessage = "ERROR: $e";
        });
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(body: Center(child: Text(latestMessage))),
    );
  }
}

This migration guide might help: https://dart.dev/interop/js-interop/package-web

I appreciate your help in refactoring the deprecated code, and your work overall in maintaining Pubnub : )
Switching to WASM is showing significant performance gains.

Thank you.

[mohitpubnub]

Thanks for pointing out the exact details.

Yes, It looks like we need to do couple of changes in order to make package compatible to WASM.

We will work upon it and test the compatibility

[Ali-Toosi]

Hello, was just wondering if there is anything I can help with to move this one forward. Unless there are other changes needed in addition to the migration from html to web, I can open a PR for that if it helps.

[stephenlb]

Hi @Ali-Toosi thank you for keeping this thread active

[mohitpubnub]

@Ali-Toosi can you give it a try with v7.1.0
This should fix the issue you have faced.

[Ali-Toosi]

Hey @mohitpubnub it looks like it's working! Thank you very much : )