import fetch from "node-fetch"; import WebSocket from "ws"; import * as logger from "./logger.js"; import { setTimeout } from "timers/promises"; /* Rerror 0x01 Tqueue 0x02 Rqueue 0x03 Tcancel 0x04 Rcancel 0x05 Twait 0x06 Rwait 0x07 Rinit 0x08 */ const Rerror = 0x01; const Tqueue = 0x02; const Rqueue = 0x03; const Tcancel = 0x04; const Rcancel = 0x05; const Twait = 0x06; const Rwait = 0x07; const Rinit = 0x08; class ImageConnection { constructor(host, auth, tls = false) { this.requests = new Map(); this.host = host; this.port = 3762; this.auth = auth; this.tag = null; this.disconnected = false; this.njobs = 0; this.max = 0; this.formats = {}; this.wsproto = null; if (tls) { this.wsproto = "wss"; } else { this.wsproto = "ws"; } this.sockurl = `${this.wsproto}://${host}:${this.port}/sock`; this.conn = new WebSocket(this.sockurl, { headers: { "Authentication": auth && auth !== "" ? auth : undefined } }); let httpproto; if (tls) { httpproto = "https"; } else { httpproto = "http"; } this.httpurl = `${httpproto}://${host}:${this.port}/image`; this.conn.on("message", (msg) => this.onMessage(msg)); this.conn.once("error", (err) => this.onError(err)); this.conn.once("close", () => this.onClose()); } onMessage(msg) { const op = msg.readUint8(0); if (op === Rinit) { this.max = msg.readUint16LE(3); this.formats = JSON.parse(msg.toString("utf8", 5)); return; } const tag = msg.readUint16LE(1); const promise = this.requests.get(tag); this.requests.delete(tag); if (op === Rqueue) this.njobs++; if (op === Rcancel || op === Rwait) this.njobs--; if (op === Rerror) { this.njobs--; promise.reject(new Error(msg.slice(3, msg.length).toString())); return; } promise.resolve(); } onError(e) { logger.error(e.toString()); } async onClose() { for (const promise of this.requests.values()) { promise.reject(new Error("Request ended prematurely due to a closed connection")); } this.requests.clear(); if (!this.disconnected) { logger.warn(`Lost connection to ${this.host}:${this.port}, attempting to reconnect in 5 seconds...`); await setTimeout(5000); this.conn = new WebSocket(this.sockurl, { headers: { "Authentication": this.auth } }); this.conn.on("message", (msg) => this.onMessage(msg)); this.conn.once("error", (err) => this.onError(err)); this.conn.once("close", () => this.onClose()); } this.disconnected = false; } close() { this.disconnected = true; this.conn.close(); } queue(jobid, jobobj) { const str = JSON.stringify(jobobj); const buf = Buffer.alloc(4); buf.writeUint32LE(jobid); return this.do(Tqueue, Buffer.concat([buf, Buffer.from(str)])); } wait(jobid) { const buf = Buffer.alloc(4); buf.writeUint32LE(jobid); return this.do(Twait, buf); } cancel(jobid) { const buf = Buffer.alloc(4); buf.writeUint32LE(jobid); return this.do(Tcancel, buf); } async getOutput(jobid) { const req = await fetch(`${this.httpurl}?id=${jobid}`, { headers: { "Authentication": this.auth && this.auth !== "" ? this.auth : undefined } }); const contentType = req.headers.get("Content-Type"); let type; switch (contentType) { case "image/gif": type = "gif"; break; case "image/png": type = "png"; break; case "image/jpeg": type = "jpg"; break; case "image/webp": type = "webp"; break; } return { buffer: Buffer.from(await req.arrayBuffer()), type }; } async do(op, data) { const buf = Buffer.alloc(1 + 2); const tag = this.tag++; buf.writeUint8(op); buf.writeUint16LE(tag, 1); this.conn.send(Buffer.concat([buf, data])); const promise = new Promise((resolve, reject) => { this.requests.set(tag, { resolve, reject }); }); return promise; } } export default ImageConnection;