Upload processed audio tracks to S3

server/utils/audio-files.ts

@@ -1,47 +1,57 @@
-import { unlink } from "node:fs/promises"
+import { mkdtemp, readFile, rm, writeFile } from "node:fs/promises"
+import os from "node:os"
 import path from "node:path"
 import Ffmpeg from "fluent-ffmpeg"
-import type { H3Event } from "h3"
-import { resolveUploadFile } from "./upload-files"
 
-export async function getAudioDuration(event: H3Event, relativePath: string): Promise<number> {
-	if (!relativePath) throw new Error("filePath is undefined")
-	const { path: sourcePath } = await resolveUploadFile(event, relativePath)
+const jobs: Array<[string, string, string, string, string]> = [
+	["128k", "mp3", "libmp3lame", "low.mp3", "audio/mpeg"],
+	["256k", "mp3", "libmp3lame", "mid.mp3", "audio/mpeg"],
+	["96k", "mp4", "aac", "low.m4a", "audio/mp4"],
+	["192k", "mp4", "aac", "mid.m4a", "audio/mp4"],
+	["320k", "mp4", "aac", "high.m4a", "audio/mp4"],
+]
+
+function getDuration(sourcePath: string): Promise<number> {
 	return new Promise((resolve, reject) => {
 		Ffmpeg.ffprobe(sourcePath, (error, metadata) => {
-			if (error) return reject(0)
+			if (error) return reject(error)
 			if (metadata.format.duration) return resolve(metadata.format.duration)
-			reject(0)
+			reject(new Error("Unable to read audio duration"))
 		})
 	})
 }
 
-export async function processAudioFile(event: H3Event, relativePath: string) {
-	if (!relativePath) throw new Error("filePath is undefined")
-	const { path: sourcePath } = await resolveUploadFile(event, relativePath)
-	const directory = path.dirname(sourcePath)
-	const jobs: Array<[string, string, string]> = [
-		["128k", "mp3", "libmp3lame"],
-		["256k", "mp3", "libmp3lame"],
-		["96k", "mp4", "aac"],
-		["192k", "mp4", "aac"],
-		["320k", "mp4", "aac"],
-	]
-	const names = ["low.mp3", "mid.mp3", "low.m4a", "mid.m4a", "high.m4a"]
+function transcode(sourcePath: string, outputPath: string, bitrate: string, format: string, codec: string) {
+	return new Promise<void>((resolve, reject) => {
+		Ffmpeg(sourcePath)
+			.noVideo()
+			.audioBitrate(bitrate)
+			.toFormat(format)
+			.audioCodec(codec)
+			.on("end", () => resolve())
+			.on("error", reject)
+			.save(outputPath)
+	})
+}
 
-	await Promise.all(
-		jobs.map(([bitrate, format, codec], index) =>
-			new Promise<void>((resolve, reject) => {
-				Ffmpeg(sourcePath)
-					.noVideo()
-					.audioBitrate(bitrate)
-					.toFormat(format)
-					.audioCodec(codec)
-					.on("end", () => resolve())
-					.on("error", reject)
-					.save(path.join(directory, names[index]!))
-			}),
-		),
-	)
-	await unlink(sourcePath)
+export async function prepareAudioUpload(data: Buffer, extension: string) {
+	const directory = await mkdtemp(path.join(os.tmpdir(), "music-v2-audio-"))
+	const sourcePath = path.join(directory, `original${extension ? `.${extension}` : ""}`)
+	try {
+		await writeFile(sourcePath, data)
+		const duration = await getDuration(sourcePath)
+		const completed = await Promise.allSettled(jobs.map(([bitrate, format, codec, name]) =>
+			transcode(sourcePath, path.join(directory, name), bitrate, format, codec),
+		))
+		const failedJob = completed.find((result) => result.status === "rejected")
+		if (failedJob?.status === "rejected") throw failedJob.reason
+		const renditions = await Promise.all(jobs.map(async ([, , , name, contentType]) => ({
+			name,
+			contentType,
+			body: await readFile(path.join(directory, name)),
+		})))
+		return { duration, original: data, renditions }
+	} finally {
+		await rm(directory, { recursive: true, force: true })
+	}
 }