Initial commit to release

packages/cli/src/Push.ts

@@ -0,0 +1,86 @@
+// @ts-ignore
+import * as sseChannel from 'sse-channel';
+import * as express from 'express';
+
+import {
+	IPushData,
+	IPushDataType,
+} from '.';
+
+export class Push {
+	private channel: sseChannel;
+	private connections: {
+		[key: string]: express.Response;
+	} = {};
+
+
+	constructor() {
+		this.channel = new sseChannel({
+			cors: {
+				// Allow access also from frontend when developing
+				origins: ['http://localhost:8080'],
+			},
+		});
+
+		this.channel.on('disconnect', (channel: string, res: express.Response) => {
+			if (res.req !== undefined) {
+				delete this.connections[res.req.query.sessionId];
+			}
+		});
+	}
+
+
+	/**
+	 * Adds a new push connection
+	 *
+	 * @param {string} sessionId The id of the session
+	 * @param {express.Request} req The request
+	 * @param {express.Response} res The response
+	 * @memberof Push
+	 */
+	add(sessionId: string, req: express.Request, res: express.Response) {
+		if (this.connections[sessionId] !== undefined) {
+			// Make sure to remove existing connection with the same session
+			// id if one exists already
+			this.connections[sessionId].end();
+			this.channel.removeClient(this.connections[sessionId]);
+		}
+
+		this.connections[sessionId] = res;
+		this.channel.addClient(req, res);
+	}
+
+
+	/**
+	 * Sends data to the client which is connected via a specific session
+	 *
+	 * @param {string} sessionId The session id of client to send data to
+	 * @param {string} type Type of data to send
+	 * @param {*} data
+	 * @memberof Push
+	 */
+	send(sessionId: string, type: IPushDataType, data: any) { // tslint:disable-line:no-any
+		if (this.connections[sessionId] === undefined) {
+			// TODO: Log that properly!
+			console.error(`The session "${sessionId}" is not registred.`);
+			return;
+		}
+
+		const sendData: IPushData = {
+			type,
+			data,
+		};
+
+		this.channel.send(JSON.stringify(sendData));
+	}
+}
+
+let activePushInstance: Push | undefined;
+
+export function getInstance(): Push {
+	if (activePushInstance === undefined) {
+		activePushInstance = new Push();
+	}
+
+	return activePushInstance;
+}