Sharkey/src/streaming.ts
2021-06-27 21:17:38 +09:00

344 lines
8.3 KiB
TypeScript
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

import autobind from 'autobind-decorator';
import { EventEmitter } from 'eventemitter3';
import ReconnectingWebsocket from 'reconnecting-websocket';
import { stringify } from 'querystring';
import { markRaw } from '@vue/reactivity';
import { BroadcasrEvents, Channels } from './streaming.types';
function urlQuery(obj: {}): string {
return stringify(Object.entries(obj)
.filter(([, v]) => Array.isArray(v) ? v.length : v !== undefined)
.reduce((a, [k, v]) => (a[k] = v, a), {} as Record<string, any>));
}
type StreamEvents = {
_connected_: void;
_disconnected_: void;
} & BroadcasrEvents;
/**
* Misskey stream connection
*/
export default class Stream extends EventEmitter<StreamEvents> {
private stream: ReconnectingWebsocket;
public state: 'initializing' | 'reconnecting' | 'connected' = 'initializing';
private sharedConnectionPools: Pool[] = [];
private sharedConnections: SharedConnection[] = [];
private nonSharedConnections: NonSharedConnection[] = [];
constructor(origin: string, user: { token: string; } | null, options?: {
WebSocket?: any;
}) {
super();
options = options || { };
const query = urlQuery({
i: user?.token,
// To prevent cache of an HTML such as error screen
_t: Date.now(),
});
this.stream = new ReconnectingWebsocket(`${origin.replace('http://', 'ws://').replace('https://', 'wss://')}/streaming?${query}`, '', {
minReconnectionDelay: 1, // https://github.com/pladaria/reconnecting-websocket/issues/91
WebSocket: options.WebSocket
});
this.stream.addEventListener('open', this.onOpen);
this.stream.addEventListener('close', this.onClose);
this.stream.addEventListener('message', this.onMessage);
}
@autobind
public useChannel<C extends keyof Channels>(channel: C, params?: Channels[C]['params'], name?: string): Connection<Channels[C]> {
if (params) {
return this.connectToChannel(channel, params);
} else {
return this.useSharedConnection(channel, name);
}
}
@autobind
private useSharedConnection<C extends keyof Channels>(channel: C, name?: string): SharedConnection<Channels[C]> {
let pool = this.sharedConnectionPools.find(p => p.channel === channel);
if (pool == null) {
pool = new Pool(this, channel);
this.sharedConnectionPools.push(pool);
}
const connection = markRaw(new SharedConnection(this, channel, pool, name));
this.sharedConnections.push(connection);
return connection;
}
@autobind
public removeSharedConnection(connection: SharedConnection) {
this.sharedConnections = this.sharedConnections.filter(c => c !== connection);
}
@autobind
public removeSharedConnectionPool(pool: Pool) {
this.sharedConnectionPools = this.sharedConnectionPools.filter(p => p !== pool);
}
@autobind
private connectToChannel<C extends keyof Channels>(channel: C, params: Channels[C]['params']): NonSharedConnection<Channels[C]> {
const connection = markRaw(new NonSharedConnection(this, channel, params));
this.nonSharedConnections.push(connection);
return connection;
}
@autobind
public disconnectToChannel(connection: NonSharedConnection) {
this.nonSharedConnections = this.nonSharedConnections.filter(c => c !== connection);
}
/**
* Callback of when open connection
*/
@autobind
private onOpen() {
const isReconnect = this.state === 'reconnecting';
this.state = 'connected';
this.emit('_connected_');
// チャンネル再接続
if (isReconnect) {
for (const p of this.sharedConnectionPools)
p.connect();
for (const c of this.nonSharedConnections)
c.connect();
}
}
/**
* Callback of when close connection
*/
@autobind
private onClose() {
if (this.state === 'connected') {
this.state = 'reconnecting';
this.emit('_disconnected_');
}
}
/**
* Callback of when received a message from connection
*/
@autobind
private onMessage(message: { data: string; }) {
const { type, body } = JSON.parse(message.data);
if (type === 'channel') {
const id = body.id;
let connections: Connection[];
connections = this.sharedConnections.filter(c => c.id === id);
if (connections.length === 0) {
const found = this.nonSharedConnections.find(c => c.id === id);
if (found) {
connections = [found];
}
}
for (const c of connections.filter(c => c != null)) {
c.emit(body.type, Object.freeze(body.body));
c.inCount++;
}
} else {
this.emit(type, Object.freeze(body));
}
}
/**
* Send a message to connection
*/
@autobind
public send(typeOrPayload: any, payload?: any) {
const data = payload === undefined ? typeOrPayload : {
type: typeOrPayload,
body: payload
};
this.stream.send(JSON.stringify(data));
}
/**
* Close this connection
*/
@autobind
public close() {
this.stream.close();
}
}
let idCounter = 0;
// TODO: これらのクラスを Stream クラスの内部クラスにすれば余計なメンバをpublicにしないで済むかも
class Pool {
public channel: string;
public id: string;
protected stream: Stream;
public users = 0;
private disposeTimerId: any;
private isConnected = false;
constructor(stream: Stream, channel: string) {
this.channel = channel;
this.stream = stream;
this.id = (++idCounter).toString();
this.stream.on('_disconnected_', this.onStreamDisconnected);
}
@autobind
private onStreamDisconnected() {
this.isConnected = false;
}
@autobind
public inc() {
if (this.users === 0 && !this.isConnected) {
this.connect();
}
this.users++;
// タイマー解除
if (this.disposeTimerId) {
clearTimeout(this.disposeTimerId);
this.disposeTimerId = null;
}
}
@autobind
public dec() {
this.users--;
// そのコネクションの利用者が誰もいなくなったら
if (this.users === 0) {
// また直ぐに再利用される可能性があるので、一定時間待ち、
// 新たな利用者が現れなければコネクションを切断する
this.disposeTimerId = setTimeout(() => {
this.disconnect();
}, 3000);
}
}
@autobind
public connect() {
if (this.isConnected) return;
this.isConnected = true;
this.stream.send('connect', {
channel: this.channel,
id: this.id
});
}
@autobind
private disconnect() {
this.stream.off('_disconnected_', this.onStreamDisconnected);
this.stream.send('disconnect', { id: this.id });
this.stream.removeSharedConnectionPool(this);
}
}
abstract class Connection<Channel extends Channels[keyof Channels] = any> extends EventEmitter<Channel['events']> {
public channel: string;
protected stream: Stream;
public abstract id: string;
public name?: string; // for debug
public inCount: number = 0; // for debug
public outCount: number = 0; // for debug
constructor(stream: Stream, channel: string, name?: string) {
super();
this.stream = stream;
this.channel = channel;
this.name = name;
}
@autobind
public send(id: string, typeOrPayload: any, payload?: any) {
const type = payload === undefined ? typeOrPayload.type : typeOrPayload;
const body = payload === undefined ? typeOrPayload.body : payload;
this.stream.send('ch', {
id: id,
type: type,
body: body
});
this.outCount++;
}
public abstract dispose(): void;
}
class SharedConnection<Channel extends Channels[keyof Channels] = any> extends Connection<Channel> {
private pool: Pool;
public get id(): string {
return this.pool.id;
}
constructor(stream: Stream, channel: string, pool: Pool, name?: string) {
super(stream, channel, name);
this.pool = pool;
this.pool.inc();
}
@autobind
public send(typeOrPayload: any, payload?: any) {
super.send(this.pool.id, typeOrPayload, payload);
}
@autobind
public dispose() {
this.pool.dec();
this.removeAllListeners();
this.stream.removeSharedConnection(this);
}
}
class NonSharedConnection<Channel extends Channels[keyof Channels] = any> extends Connection<Channel> {
public id: string;
protected params: Channel['params'];
constructor(stream: Stream, channel: string, params: Channel['params']) {
super(stream, channel);
this.params = params;
this.id = (++idCounter).toString();
this.connect();
}
@autobind
public connect() {
this.stream.send('connect', {
channel: this.channel,
id: this.id,
params: this.params
});
}
@autobind
public send(typeOrPayload: any, payload?: any) {
super.send(this.id, typeOrPayload, payload);
}
@autobind
public dispose() {
this.removeAllListeners();
this.stream.send('disconnect', { id: this.id });
this.stream.disconnectToChannel(this);
}
}