Queue OCR & ASR work

src/audio.ts

@@ -5,37 +5,59 @@ import {canDiarization} from './asr.ts';
 import {dirname, join} from 'path';
 
 export class Audio {
+	private busy = false;
+	private currentJob: any;
+	private queue: Array<{file: string, model: string, speaker: boolean | 'id', modelDir: string, token: string, resolve: any, reject: any}> = [];
+	private worker: Worker | null = null;
+
 	constructor(private ai: Ai) {}
 
+	private processQueue() {
+		if(this.busy || !this.queue.length) return;
+
+		this.busy = true;
+		const job = this.queue.shift()!;
+		if(!this.worker) {
+			this.worker = new Worker(join(dirname(fileURLToPath(import.meta.url)), 'asr.js'));
+			this.worker.on('message', this.handleMessage.bind(this));
+			this.worker.on('error', this.handleError.bind(this));
+		}
+
+		this.currentJob = job;
+		this.worker.postMessage({file: job.file, model: job.model, speaker: job.speaker, modelDir: job.modelDir, token: job.token});
+	}
+
+	private handleMessage({text, warning, error}: any) {
+		const job = this.currentJob!;
+		this.busy = false;
+		if(error) job.reject(new Error(error));
+		else {
+			if(warning) console.warn(warning);
+			job.resolve(text);
+		}
+		this.processQueue();
+	}
+
+	private handleError(err: Error) {
+		if(this.currentJob) {
+			this.currentJob.reject(err);
+			this.busy = false;
+			this.processQueue();
+		}
+	}
+
 	asr(file: string, options: { model?: string; speaker?: boolean | 'id' } = {}): AbortablePromise<string | null> {
 		const { model = this.ai.options.asr || 'whisper-base', speaker = false } = options;
 		let aborted = false;
 		const abort = () => { aborted = true; };
-
 		let p = new Promise<string | null>((resolve, reject) => {
-			const worker = new Worker(join(dirname(fileURLToPath(import.meta.url)), 'asr.js'));
-			const handleMessage = ({ text, warning, error }: any) => {
-				setTimeout(() => worker.terminate(), 1000);
-				if(aborted) return;
-				if(error) reject(new Error(error));
-				else {
-					if(warning) console.warn(warning);
-					resolve(text);
-				}
-			};
-			const handleError = (err: Error) => {
-				setTimeout(() => worker.terminate(), 1000);
-				if(!aborted) reject(err);
-			};
-			worker.on('message', handleMessage);
-			worker.on('error', handleError);
-			worker.on('exit', (code) => {
-				if(code !== 0 && !aborted) reject(new Error(`Worker exited with code ${code}`));
+			this.queue.push({file, model, speaker, modelDir: <string>this.ai.options.path, token: <string>this.ai.options.hfToken,
+				resolve: (text: string | null) => !aborted && resolve(text),
+				reject: (err: Error) => !aborted && reject(err)
 			});
-			worker.postMessage({file, model, speaker, modelDir: this.ai.options.path, token: this.ai.options.hfToken});
+			this.processQueue();
 		});
 
-		// Name speakers using AI
 		if(options.speaker == 'id') {
 			if(!this.ai.language.defaultModel) throw new Error('Configure an LLM for advanced ASR speaker detection');
 			p = p.then(async transcript => {