IOWebSocketChannel Flutter & GraphQL Apollo - flutter

Question

I'm having an issue connecting to a GraphQL endpoint using Web-sockets.
The issues are noted in the comments. I cannot get this working. It works on the browser (separate test application) so the server is fine.
IOWebSocketChannel? _channel;
StreamSubscription? _getSubscription;
connectToWebsocket(BuildContext context) {
// Nothing to listen to. Auth users only.
final auth = authProviderRead(context);
if (auth.modelUser == null) {
return;
}
_channel?.sink.close();
_getSubscription?.cancel();
final headers = {
"Authorization": auth.jwt ?? "",
"Content-Type": "application/json",
};
_channel = IOWebSocketChannel.connect(
Uri.parse(getWebStockUrl()),
headers: headers,
protocols: ["graphql-ws"],
);
// Fails: Just fires "onDone"
// _channel?.sink.add(jsonEncode({"data": subscriptionQuery}));
// Fails with {"type":"connection_error","payload":{"message":"Cannot read properties of undefined (reading 'Authorization')"}}
// _channel?.sink.add(json.encode({"type": "connection_init"}));
// Fails with {"type":"error","payload":{"message":"Invalid message type!"}}
// _channel?.sink.add(jsonEncode(
// {
// "type": "data",
// "query": subscriptionQuery,
// },
// ));
_getSubscription = _channel!.stream.listen((message) {
// Is never fired?
if (kDebugMode) {
print("Got live message");
print(message);
}
// channel!.sink.add('received!');
// channel!.sink.close();
})
..onData((data) {
if (kDebugMode) {
print("onData - WebSocket");
print(data);
}
})
..onDone(() {
if (kDebugMode) {
print("onDone - WebSocket");
}
})
..onError((e) {
if (kDebugMode) {
print("onError - WebSocket");
print(e);
}
});
}
const subscriptionQuery = r'''
subscription Subscription {
gotChatMessage {
messageResults {
message {
markdown
}
}
}
}
''';

Answer 1

I figure it out, there are some additional things that it requires.
From https://github.com/apollographql/subscriptions-transport-ws/blob/master/src/message-types.ts
_channel?.sink.add(jsonEncode({
"type": "connection_init",
"payload": {"Authorization": auth.jwt}
}));
_channel?.sink.add(jsonEncode({
"type": "start",
"payload": {"query": subscriptionQuery}
}));