Get Nostr Events from a Relay

GetNostrEvents.dart

import 'dart:io';
import 'dart:convert';

String serverUrl     = 'wss://nostr-pub.wellorder.net';
var    userPublickey = "3235036bd0957dfb27ccda02d452d7c763be40c91a1ac082ba6983b25238388c";
var    userSubReq    = '["REQ","latest",{ "authors": ["$userPublickey"], "limit": 5  } ]';

class EventData {
  String id;
  String pubkey;
  String content;
  EventData(this.id, this.pubkey, this.content);
  factory EventData.fromJson(dynamic json) {
    return EventData(json['id'] as String, json['pubkey'] as String, json['content'] as String);
  }

  @override
  String toString() {
    return 'id     : $id\nAuthor : $pubkey\nMessage: $content\n';
  }
}

class Event {
  String event;
  String id;
  EventData eventData;
  Event(this.event, this.id, this.eventData);
  factory Event.fromJson(dynamic json) {
    if( json.length < 3) {
      String e = "";
      if(json.length > 1) e = json[0];
      else e = "";
      return Event(e,"",EventData("empty","",""));
    }
    else
      return Event(json[0] as String, json[1] as String,  EventData.fromJson(json[2]) );
  }

  @override 
  String toString() {
    return '$eventData';
  }
}

void main()  {
  Future<WebSocket> fws = WebSocket.connect(serverUrl);
  List<String> events = [];
  fws.then((WebSocket ws) {
    ws.listen(
        (d) { events.add( d); },
        onError: (e) { print("error"); print(e);  },
        onDone:  () { print('in onDone'); ws.close() ; exit(0);}
    );
    ws.add(userSubReq);
  });

  Future.delayed(const Duration(milliseconds: 2000), () {
    for( int i = 0; i < events.length; i++) {
      //print('Event number $i: ${events[i]}');
      Event e = Event.fromJson(jsonDecode(events[i]));
      print('-------+\n$e');
    }

    exit(0);
  });
}

This works:

import 'dart:io';

String socketServerUrl = 'wss://ws.postman-echo.com/raw';
//String socketServerUrl = 'ws://echo.FAILS.org/';

void main() {

  Future<WebSocket> futureWebSocket = WebSocket.connect(socketServerUrl);
  futureWebSocket.then((WebSocket ws) {
   
    WebSocket  webSocket = ws;
    print(webSocket.readyState);

    webSocket.listen(
        (d) { print('received: $d'); },
        onError: (e) { print("error"); print(e); }, 
        onDone: () => print("done")
    );

    // send message
    print('sent hello world');
    webSocket.add('hello world');

    Future.delayed(const Duration(milliseconds: 5000), () {
      print('Closing connection after 5 second future delay.');
      ws.close();
    });
  
    
  });