aspnetcore/clients/ts/signalr/src/HubConnection.ts

381 lines
14 KiB
TypeScript

// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
import { HandshakeProtocol, HandshakeRequestMessage, HandshakeResponseMessage } from "./HandshakeProtocol";
import { HttpConnection, IHttpConnectionOptions } from "./HttpConnection";
import { IConnection } from "./IConnection";
import { CancelInvocationMessage, CompletionMessage, HubMessage, IHubProtocol, InvocationMessage, MessageType, StreamInvocationMessage, StreamItemMessage } from "./IHubProtocol";
import { ILogger, LogLevel } from "./ILogger";
import { JsonHubProtocol } from "./JsonHubProtocol";
import { NullLogger } from "./Loggers";
import { IStreamResult } from "./Stream";
import { TextMessageFormat } from "./TextMessageFormat";
import { createLogger, Subject } from "./Utils";
export { JsonHubProtocol };
export interface IHubConnectionOptions extends IHttpConnectionOptions {
protocol?: IHubProtocol;
timeoutInMilliseconds?: number;
}
const DEFAULT_TIMEOUT_IN_MS: number = 30 * 1000;
export class HubConnection {
private readonly connection: IConnection;
private readonly logger: ILogger;
private protocol: IHubProtocol;
private handshakeProtocol: HandshakeProtocol;
private callbacks: { [invocationId: string]: (invocationEvent: StreamItemMessage | CompletionMessage, error?: Error) => void };
private methods: { [name: string]: Array<(...args: any[]) => void> };
private id: number;
private closedCallbacks: Array<(error?: Error) => void>;
private timeoutHandle: NodeJS.Timer;
private timeoutInMilliseconds: number;
private receivedHandshakeResponse: boolean;
constructor(url: string, options?: IHubConnectionOptions);
constructor(connection: IConnection, options?: IHubConnectionOptions);
constructor(urlOrConnection: string | IConnection, options: IHubConnectionOptions = {}) {
options = options || {};
this.timeoutInMilliseconds = options.timeoutInMilliseconds || DEFAULT_TIMEOUT_IN_MS;
this.protocol = options.protocol || new JsonHubProtocol();
this.handshakeProtocol = new HandshakeProtocol();
if (typeof urlOrConnection === "string") {
this.connection = new HttpConnection(urlOrConnection, options);
} else {
this.connection = urlOrConnection;
}
this.logger = createLogger(options.logger);
this.connection.onreceive = (data: any) => this.processIncomingData(data);
this.connection.onclose = (error?: Error) => this.connectionClosed(error);
this.callbacks = {};
this.methods = {};
this.closedCallbacks = [];
this.id = 0;
}
public async start(): Promise<void> {
const handshakeRequest: HandshakeRequestMessage = {
protocol: this.protocol.name,
version: this.protocol.version,
};
this.logger.log(LogLevel.Debug, "Starting HubConnection.");
this.receivedHandshakeResponse = false;
await this.connection.start(this.protocol.transferFormat);
this.logger.log(LogLevel.Debug, "Sending handshake request.");
await this.connection.send(this.handshakeProtocol.writeHandshakeRequest(handshakeRequest));
this.logger.log(LogLevel.Information, `Using HubProtocol '${this.protocol.name}'.`);
// defensively cleanup timeout in case we receive a message from the server before we finish start
this.cleanupTimeout();
this.configureTimeout();
}
public stop(): Promise<void> {
this.logger.log(LogLevel.Debug, "Stopping HubConnection.");
this.cleanupTimeout();
return this.connection.stop();
}
public stream<T = any>(methodName: string, ...args: any[]): IStreamResult<T> {
const invocationDescriptor = this.createStreamInvocation(methodName, args);
const subject = new Subject<T>(() => {
const cancelInvocation: CancelInvocationMessage = this.createCancelInvocation(invocationDescriptor.invocationId);
const cancelMessage: any = this.protocol.writeMessage(cancelInvocation);
delete this.callbacks[invocationDescriptor.invocationId];
return this.connection.send(cancelMessage);
});
this.callbacks[invocationDescriptor.invocationId] = (invocationEvent: CompletionMessage | StreamItemMessage, error?: Error) => {
if (error) {
subject.error(error);
return;
}
if (invocationEvent.type === MessageType.Completion) {
if (invocationEvent.error) {
subject.error(new Error(invocationEvent.error));
} else {
subject.complete();
}
} else {
subject.next((invocationEvent.item) as T);
}
};
const message = this.protocol.writeMessage(invocationDescriptor);
this.connection.send(message)
.catch((e) => {
subject.error(e);
delete this.callbacks[invocationDescriptor.invocationId];
});
return subject;
}
public send(methodName: string, ...args: any[]): Promise<void> {
const invocationDescriptor = this.createInvocation(methodName, args, true);
const message = this.protocol.writeMessage(invocationDescriptor);
return this.connection.send(message);
}
public invoke<T = any>(methodName: string, ...args: any[]): Promise<T> {
const invocationDescriptor = this.createInvocation(methodName, args, false);
const p = new Promise<any>((resolve, reject) => {
this.callbacks[invocationDescriptor.invocationId] = (invocationEvent: StreamItemMessage | CompletionMessage, error?: Error) => {
if (error) {
reject(error);
return;
}
if (invocationEvent.type === MessageType.Completion) {
const completionMessage = invocationEvent as CompletionMessage;
if (completionMessage.error) {
reject(new Error(completionMessage.error));
} else {
resolve(completionMessage.result);
}
} else {
reject(new Error(`Unexpected message type: ${invocationEvent.type}`));
}
};
const message = this.protocol.writeMessage(invocationDescriptor);
this.connection.send(message)
.catch((e) => {
reject(e);
delete this.callbacks[invocationDescriptor.invocationId];
});
});
return p;
}
public on(methodName: string, newMethod: (...args: any[]) => void) {
if (!methodName || !newMethod) {
return;
}
methodName = methodName.toLowerCase();
if (!this.methods[methodName]) {
this.methods[methodName] = [];
}
// Preventing adding the same handler multiple times.
if (this.methods[methodName].indexOf(newMethod) !== -1) {
return;
}
this.methods[methodName].push(newMethod);
}
public off(methodName: string, method?: (...args: any[]) => void) {
if (!methodName) {
return;
}
methodName = methodName.toLowerCase();
const handlers = this.methods[methodName];
if (!handlers) {
return;
}
if (method) {
const removeIdx = handlers.indexOf(method);
if (removeIdx !== -1) {
handlers.splice(removeIdx, 1);
if (handlers.length === 0) {
delete this.methods[methodName];
}
}
} else {
delete this.methods[methodName];
}
}
public onclose(callback: (error?: Error) => void) {
if (callback) {
this.closedCallbacks.push(callback);
}
}
private processIncomingData(data: any) {
this.cleanupTimeout();
if (!this.receivedHandshakeResponse) {
data = this.processHandshakeResponse(data);
this.receivedHandshakeResponse = true;
}
// Data may have all been read when processing handshake response
if (data) {
// Parse the messages
const messages = this.protocol.parseMessages(data, this.logger);
for (const message of messages) {
switch (message.type) {
case MessageType.Invocation:
this.invokeClientMethod(message);
break;
case MessageType.StreamItem:
case MessageType.Completion:
const callback = this.callbacks[message.invocationId];
if (callback != null) {
if (message.type === MessageType.Completion) {
delete this.callbacks[message.invocationId];
}
callback(message);
}
break;
case MessageType.Ping:
// Don't care about pings
break;
case MessageType.Close:
this.logger.log(LogLevel.Information, "Close message received from server.");
this.connection.stop(message.error ? new Error("Server returned an error on close: " + message.error) : null);
break;
default:
this.logger.log(LogLevel.Warning, "Invalid message type: " + message.type);
break;
}
}
}
this.configureTimeout();
}
private processHandshakeResponse(data: any): any {
let responseMessage: HandshakeResponseMessage;
let remainingData: any;
try {
[remainingData, responseMessage] = this.handshakeProtocol.parseHandshakeResponse(data);
} catch (e) {
const message = "Error parsing handshake response: " + e;
this.logger.log(LogLevel.Error, message);
const error = new Error(message);
this.connection.stop(error);
throw error;
}
if (responseMessage.error) {
const message = "Server returned handshake error: " + responseMessage.error;
this.logger.log(LogLevel.Error, message);
this.connection.stop(new Error(message));
} else {
this.logger.log(LogLevel.Debug, "Server handshake complete.");
}
return remainingData;
}
private configureTimeout() {
if (!this.connection.features || !this.connection.features.inherentKeepAlive) {
// Set the timeout timer
this.timeoutHandle = setTimeout(() => this.serverTimeout(), this.timeoutInMilliseconds);
}
}
private serverTimeout() {
// The server hasn't talked to us in a while. It doesn't like us anymore ... :(
// Terminate the connection
this.connection.stop(new Error("Server timeout elapsed without receiving a message from the server."));
}
private invokeClientMethod(invocationMessage: InvocationMessage) {
const methods = this.methods[invocationMessage.target.toLowerCase()];
if (methods) {
methods.forEach((m) => m.apply(this, invocationMessage.arguments));
if (invocationMessage.invocationId) {
// This is not supported in v1. So we return an error to avoid blocking the server waiting for the response.
const message = "Server requested a response, which is not supported in this version of the client.";
this.logger.log(LogLevel.Error, message);
this.connection.stop(new Error(message));
}
} else {
this.logger.log(LogLevel.Warning, `No client method with the name '${invocationMessage.target}' found.`);
}
}
private connectionClosed(error?: Error) {
const callbacks = this.callbacks;
this.callbacks = {};
Object.keys(callbacks)
.forEach((key) => {
const callback = callbacks[key];
callback(undefined, error ? error : new Error("Invocation canceled due to connection being closed."));
});
this.cleanupTimeout();
this.closedCallbacks.forEach((c) => c.apply(this, [error]));
}
private cleanupTimeout(): void {
if (this.timeoutHandle) {
clearTimeout(this.timeoutHandle);
}
}
private createInvocation(methodName: string, args: any[], nonblocking: boolean): InvocationMessage {
if (nonblocking) {
return {
arguments: args,
target: methodName,
type: MessageType.Invocation,
};
} else {
const id = this.id;
this.id++;
return {
arguments: args,
invocationId: id.toString(),
target: methodName,
type: MessageType.Invocation,
};
}
}
private createStreamInvocation(methodName: string, args: any[]): StreamInvocationMessage {
const id = this.id;
this.id++;
return {
arguments: args,
invocationId: id.toString(),
target: methodName,
type: MessageType.StreamInvocation,
};
}
private createCancelInvocation(id: string): CancelInvocationMessage {
return {
invocationId: id,
type: MessageType.CancelInvocation,
};
}
}