public static void Main(string[] args) { // get the subscription handler ready (tracks websocket clients and their subscriptions) _subscriptionHandler = new SubscriptionHandler(); // get the dataHandler ready (handles incoming blocks and transactions, compares to client subscriptions using the subscription handler) _dataHandler = new DataHandler(_subscriptionHandler); // start with a ZMQ connection for blocks var blockConsumer = new BlockConsumer(_dataHandler.HandleBlock); var zmqBlockClient = new ZMQClient(Config.GetConfigString("ZMQBlockHostname"), Config.GetConfigInt("ZMQBlockPort"), "rawblock", (frameHeader, data, frameCounter) => blockConsumer.EnqueueTask(data, frameCounter)); // start a ZMQ subscription for transactions var transactionConsumer = new TransactionConsumer(_dataHandler.HandleTransaction); var zmqTxClient = new ZMQClient(Config.GetConfigString("ZMQTxHostname"), Config.GetConfigInt("ZMQTxPort"), "rawtx", (frameHeader, data, frameCounter) => transactionConsumer.EnqueueTask(data, frameCounter)); // initialize websocket server // TODO: we need an x509 certificate including key to use secure (wss) - add to application config options _server = new WebsocketServer(IPAddress.Parse(Config.GetConfigString("WebsocketBindIP")), Config.GetConfigInt("WebsocketBindPort"), false, false) // restart websocket listener automatically { RestartAfterListenError = true }; // start the websocket server, and add callbacks to track active sockets _server.Start(socket => { socket.OnOpen = () => { // track the connection _subscriptionHandler.AddSocket(socket); }; socket.OnClose = () => { // stop tracking this connection _subscriptionHandler.RemoveSocket(socket); }; socket.OnMessage = message => { // process incoming message MessageHandler.HandleMessage(socket, message, _subscriptionHandler); }; socket.OnError = exception => { // TODO: handle websocket exceptions }; }); }
/// <summary> /// Handles json messages: /// {"op": "block"} /// {"op": "transaction"} /// {"op": "address", "address": "[CASH_ADDRESS]"} /// {"op": "opreturn", "prefix": "[PREFIX(HEX)]"} /// {"op": "rm_block"} /// {"op": "rm_transaction"} /// {"op": "rm_address", "address": "[CASH_ADDRESS]"} /// {"op": "rm_opreturn", "prefix": "[PREFIX(HEX)]"} /// - Validates json /// - Validates parameters /// - Sends response (error or ok) /// - Adds valid subscriptions to subscription handler /// </summary> /// <param name="socket"></param> /// <param name="message"></param> /// <param name="subscriptionHandler"></param> public static void HandleMessage(IWebsocketConnection socket, string message, SubscriptionHandler subscriptionHandler) { message = message.Trim(); // check if the message is valid json if ((!message.StartsWith("{") || !message.EndsWith("}")) && (!message.StartsWith("[") || !message.EndsWith("]"))) { return; } JToken jToken; try { jToken = JToken.Parse(message); } catch (JsonReaderException jex) { socket.Send("{ \"op\": \"error\", \"error\": \"Unable to parse JSON request. " + JsonConvert.ToString(jex.Message) + "\" }"); return; } catch (Exception ex) { socket.Send("{ \"op\": \"error\", \"error\": \"Exception while parsing JSON request. " + JsonConvert.ToString(ex.Message) + "\" }"); return; } if (jToken.Type != JTokenType.Object) { socket.Send("{ \"op\": \"error\", \"error\": \"Error while parsing JSON request. Expected Object, but encountered " + jToken.Type + "\" }"); return; } var jObject = jToken.ToObject <JObject>(); if (!jObject.ContainsKey("op") || jObject["op"].Type != JTokenType.String) { socket.Send("{ \"op\": \"error\", \"error\": \"Error while parsing JSON request. Expected 'op' parameter as string.\" }"); return; } // block subscriptions if (jObject["op"].ToString().Equals("block", StringComparison.CurrentCultureIgnoreCase)) { subscriptionHandler.AddSubscription(socket, new BlockSubscription()); socket.Send("{ \"op\": \"block\", \"result\": \"ok\" }"); } // block un-subscribe else if (jObject["op"].ToString().Equals("rm_block", StringComparison.CurrentCultureIgnoreCase)) { socket.Send(subscriptionHandler.RemoveSubscription(socket, new BlockSubscription()) ? "{ \"op\": \"rm_block\", \"result\": \"ok\" }" : "{ \"op\": \"rm_block\", \"result\": \"failed\" }"); } // transaction subscriptions else if (jObject["op"].ToString().Equals("transaction", StringComparison.CurrentCultureIgnoreCase)) { subscriptionHandler.AddSubscription(socket, new TransactionSubscription()); socket.Send("{ \"op\": \"transaction\", \"result\": \"ok\" }"); } // transaction un-subscribe else if (jObject["op"].ToString().Equals("rm_transaction", StringComparison.CurrentCultureIgnoreCase)) { socket.Send(subscriptionHandler.RemoveSubscription(socket, new TransactionSubscription()) ? "{ \"op\": \"rm_transaction\", \"result\": \"ok\" }" : "{ \"op\": \"rm_transaction\", \"result\": \"failed\" }"); } // address subscriptions else if (jObject["op"].ToString().Equals("address", StringComparison.CurrentCultureIgnoreCase) || jObject["op"].ToString().Equals("rm_address", StringComparison.CurrentCultureIgnoreCase)) { if (!jObject.ContainsKey("address") || jObject["address"].Type != JTokenType.String) { socket.Send("{ \"op\": \"error\", \"error\": \"Error while parsing JSON request. Expected 'address' parameter as string.\" }"); return; } // attempt to decode cash address try { var decoded = CashAddress.DecodeCashAddress(jObject["address"].ToString()); if (jObject["op"].ToString().Equals("address", StringComparison.CurrentCultureIgnoreCase)) { subscriptionHandler.AddSubscription(socket, new AddressSubscription(decoded)); socket.Send("{ \"op\": \"address\", \"result\": \"ok\" }"); } else if (jObject["op"].ToString().Equals("rm_address", StringComparison.CurrentCultureIgnoreCase)) { socket.Send(!subscriptionHandler.RemoveSubscription(socket, new AddressSubscription(decoded)) ? "{ \"op\": \"rm_address\", \"result\": \"failed\" }" : "{ \"op\": \"rm_address\", \"result\": \"ok\" }"); } } catch (CashAddress.CashAddressException e) { socket.Send("{ \"op\": \"error\", \"error\": \"" + JsonConvert.ToString(e.Message) + " ... " + JsonConvert.ToString(e.InnerException.Message) + "\" }"); } } // op return subscriptions else if (jObject["op"].ToString().Equals("opreturn", StringComparison.CurrentCultureIgnoreCase) || jObject["op"].ToString().Equals("rm_opreturn", StringComparison.CurrentCultureIgnoreCase)) { if (!jObject.ContainsKey("prefix") || jObject["prefix"].Type != JTokenType.String) { socket.Send("{ \"op\": \"error\", \"error\": \"Error while parsing JSON request. Expected 'prefix' parameter as string.\" }"); return; } if (!IsValidHexString(jObject["prefix"].ToString())) { socket.Send("{ \"op\": \"error\", \"error\": \"Error while parsing JSON request. Expected 'prefix' parameter to be valid hex.\" }"); return; } if (jObject["prefix"].ToString().Length > 32) { socket.Send("{ \"op\": \"error\", \"error\": \"Error while parsing JSON request. Expected 'prefix' parameter to be less than 32 hex characters long.\" }"); return; } var prefix = ByteHexConverter.StringToByteArray(jObject["prefix"].ToString()); if (jObject["op"].ToString().Equals("opreturn", StringComparison.CurrentCultureIgnoreCase)) { subscriptionHandler.AddSubscription(socket, new OpReturnSubscription(prefix)); socket.Send("{ \"op\": \"opreturn\", \"result\": \"ok\" }"); } else if (subscriptionHandler.RemoveSubscription(socket, new OpReturnSubscription(prefix))) { socket.Send(!subscriptionHandler.RemoveSubscription(socket, new OpReturnSubscription(prefix)) ? "{ \"op\": \"rm_opreturn\", \"result\": \"failed\" }" : "{ \"op\": \"rm_opreturn\", \"result\": \"ok\" }"); } } else { // unrecognized op command socket.Send("{ \"op\": \"error\", \"error\": \"Error while parsing JSON request. Expected valid 'op' parameter.\" }"); } }
/// <summary> /// Constructor /// </summary> /// <param name="subscriptionHandler">initialized subscription handler</param> public DataHandler(SubscriptionHandler subscriptionHandler) { _subscriptionHandler = subscriptionHandler; }