idillon | dfb9f1f | 2023-01-23 10:32:51 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2022 Savoir-faire Linux Inc. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU Affero General Public License as |
| 6 | * published by the Free Software Foundation; either version 3 of the |
| 7 | * License, or (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU Affero General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Affero General Public |
| 15 | * License along with this program. If not, see |
| 16 | * <https://www.gnu.org/licenses/>. |
| 17 | */ |
| 18 | |
| 19 | import { WebSocketMessage, WebSocketMessageTable, WebSocketMessageType } from 'jami-web-common'; |
| 20 | |
| 21 | type WebSocketCallback<T extends WebSocketMessageType> = (data: WebSocketMessageTable[T]) => void; |
| 22 | |
| 23 | type WebSocketCallbacks = { |
| 24 | [key in WebSocketMessageType]: Set<WebSocketCallback<key>>; |
| 25 | }; |
| 26 | |
| 27 | const buildWebSocketCallbacks = (): WebSocketCallbacks => { |
| 28 | const webSocketCallback = {} as WebSocketCallbacks; |
| 29 | for (const messageType of Object.values(WebSocketMessageType)) { |
| 30 | // TODO: type this properly to prevent mistakes |
| 31 | // The end result of the function is still typed properly |
| 32 | webSocketCallback[messageType] = new Set() as any; |
| 33 | } |
| 34 | return webSocketCallback; |
| 35 | }; |
| 36 | |
| 37 | export class WebSocketClient { |
| 38 | private webSocket: WebSocket | null = null; |
| 39 | private accessToken: string | null = null; |
| 40 | private callbacks: WebSocketCallbacks = buildWebSocketCallbacks(); |
| 41 | private reconnectionTimeout: ReturnType<typeof setTimeout> | null = null; |
| 42 | |
| 43 | // Queue of messages waiting for connection |
| 44 | // TODO: Add timeout (or something else) for messages that should be discarded when it takes too long |
| 45 | private sendQueue: Parameters<WebSocketClient['send']>[] = []; |
| 46 | |
| 47 | connect(apiUrl: string, accessToken: string) { |
| 48 | if (this.accessToken === accessToken) { |
| 49 | if (this.webSocket?.readyState === WebSocket.OPEN || this.webSocket?.readyState === WebSocket.CONNECTING) { |
| 50 | return; // Connection is already OK |
| 51 | } |
| 52 | } else { |
| 53 | // Clean up to make sure messages for previous token won't be sent or received accidentaly |
| 54 | this.disconnect(); |
| 55 | } |
| 56 | |
| 57 | this.accessToken = accessToken; |
| 58 | const url = new URL(apiUrl); |
| 59 | url.protocol = 'ws:'; |
| 60 | url.searchParams.set('accessToken', accessToken); |
| 61 | |
| 62 | this.webSocket = new WebSocket(url); |
| 63 | const webSocket = this.webSocket; |
| 64 | |
| 65 | webSocket.onopen = () => { |
| 66 | console.debug('WebSocket connected'); |
| 67 | |
| 68 | // Send queued messages |
| 69 | const oldSendQueue = this.sendQueue; |
| 70 | this.sendQueue = []; |
| 71 | oldSendQueue.forEach(([type, data]) => this.send(type, data)); |
| 72 | }; |
| 73 | |
| 74 | webSocket.onclose = (event) => { |
| 75 | // Involuntary disconnection. See 'disconnect' method to disconnect voluntarily. |
| 76 | console.debug(`WebSocket has been involuntarily disconnected (code: ${event.code}). Reconnecting...`); |
| 77 | this.reconnectionTimeout = setTimeout(() => this.connect(apiUrl, accessToken), 2000); |
| 78 | }; |
| 79 | |
| 80 | webSocket.onmessage = <T extends WebSocketMessageType>(event: MessageEvent<string>) => { |
| 81 | const messageString = event.data; |
| 82 | console.debug('WebSocket received message', messageString); |
| 83 | |
| 84 | const message: WebSocketMessage<T> = JSON.parse(messageString); |
| 85 | if (!message.type || !message.data) { |
| 86 | console.warn('WebSocket message is not a valid WebSocketMessage (missing type or data fields)'); |
| 87 | return; |
| 88 | } |
| 89 | |
| 90 | if (!Object.values(WebSocketMessageType).includes(message.type)) { |
| 91 | console.warn(`Invalid WebSocket message type: ${message.type}`); |
| 92 | return; |
| 93 | } |
| 94 | |
| 95 | const callbacksForType = this.callbacks[message.type]; |
| 96 | for (const callback of callbacksForType) { |
| 97 | callback(message.data); |
| 98 | } |
| 99 | }; |
| 100 | |
| 101 | webSocket.onerror = (event: Event) => { |
| 102 | console.error('WebSocket errored', event); |
| 103 | }; |
| 104 | } |
| 105 | |
| 106 | disconnect() { |
| 107 | // Cancel any previous reconnection attempt |
| 108 | if (this.reconnectionTimeout) { |
| 109 | clearTimeout(this.reconnectionTimeout); |
| 110 | this.reconnectionTimeout = null; |
| 111 | } |
| 112 | |
| 113 | this.sendQueue = []; |
| 114 | this.accessToken = null; |
| 115 | |
| 116 | if (this.webSocket) { |
| 117 | this.webSocket.onclose = (event) => |
| 118 | console.debug(`WebSocket has been voluntarily disconnected (code: ${event.code})`); |
| 119 | this.webSocket.close(); |
| 120 | this.webSocket = null; |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | bind<T extends WebSocketMessageType>(type: T, callback: (data: WebSocketMessageTable[T]) => void) { |
| 125 | const callbacksForType = this.callbacks[type]; |
| 126 | callbacksForType.add(callback); |
| 127 | } |
| 128 | |
| 129 | unbind<T extends WebSocketMessageType>(type: T, callback: (data: WebSocketMessageTable[T]) => void) { |
| 130 | const callbacksForType = this.callbacks[type]; |
| 131 | callbacksForType.delete(callback); |
| 132 | } |
| 133 | |
| 134 | send<T extends WebSocketMessageType>(type: T, data: WebSocketMessageTable[T]) { |
| 135 | if (!this.webSocket || this.webSocket.readyState !== WebSocket.OPEN) { |
| 136 | this.sendQueue.push([type, data]); |
| 137 | return; |
| 138 | } |
| 139 | this.webSocket.send(JSON.stringify({ type, data })); |
| 140 | } |
| 141 | } |