Add:Experimental embed metadata in audio files #141

server/managers/AudioMetadataManager.js

@@ -0,0 +1,137 @@
+const Path = require('path')
+const fs = require('fs-extra')
+const workerThreads = require('worker_threads')
+const Logger = require('../Logger')
+const filePerms = require('../utils/filePerms')
+const { secondsToTimestamp } = require('../utils/index')
+const { writeMetadataFile } = require('../utils/ffmpegHelpers')
+
+class AudioMetadataMangaer {
+  constructor(db, emitter, clientEmitter) {
+    this.db = db
+    this.emitter = emitter
+    this.clientEmitter = clientEmitter
+  }
+
+  async updateAudioFileMetadataForItem(user, libraryItem) {
+    var audioFiles = libraryItem.media.audioFiles
+
+    const itemAudioMetadataPayload = {
+      userId: user.id,
+      libraryItemId: libraryItem.id,
+      startedAt: Date.now(),
+      audioFiles: audioFiles.map(af => ({ index: af.index, ino: af.ino, filename: af.metadata.filename }))
+    }
+
+    this.emitter('audio_metadata_started', itemAudioMetadataPayload)
+
+    var downloadsPath = Path.join(global.MetadataPath, 'downloads')
+    var outputDir = Path.join(downloadsPath, libraryItem.id)
+    await fs.ensureDir(outputDir)
+
+    var metadataFilePath = Path.join(outputDir, 'metadata.txt')
+    await writeMetadataFile(libraryItem, metadataFilePath)
+
+    const proms = audioFiles.map(af => {
+      return this.updateAudioFileMetadata(libraryItem.id, af, outputDir, metadataFilePath)
+    })
+
+    const results = await Promise.all(proms)
+
+    Logger.debug(`[AudioMetadataManager] Finished`, results)
+
+    await fs.remove(outputDir)
+
+    const elapsed = Date.now() - itemAudioMetadataPayload.startedAt
+    Logger.debug(`[AudioMetadataManager] Elapsed ${secondsToTimestamp(elapsed)}`)
+    itemAudioMetadataPayload.results = results
+    itemAudioMetadataPayload.elapsed = elapsed
+    itemAudioMetadataPayload.finishedAt = Date.now()
+    this.emitter('audio_metadata_finished', itemAudioMetadataPayload)
+  }
+
+  updateAudioFileMetadata(libraryItemId, audioFile, outputDir, metadataFilePath) {
+    return new Promise((resolve) => {
+      const resultPayload = {
+        libraryItemId,
+        index: audioFile.index,
+        ino: audioFile.ino,
+        filename: audioFile.metadata.filename
+      }
+      this.emitter('audiofile_metadata_started', resultPayload)
+
+      Logger.debug(`[AudioFileMetadataManager] Starting audio file metadata encode for "${audioFile.metadata.filename}"`)
+
+      var outputPath = Path.join(outputDir, audioFile.metadata.filename)
+      var inputPath = audioFile.metadata.path
+      const isM4b = audioFile.metadata.format === 'm4b'
+      const ffmpegInputs = [
+        {
+          input: inputPath,
+          options: isM4b ? ['-f mp4'] : []
+        },
+        {
+          input: metadataFilePath
+        }
+      ]
+
+      /*
+        Mp4 doesnt support writing custom tags by default. Supported tags are itunes tags: https://git.videolan.org/?p=ffmpeg.git;a=blob;f=libavformat/movenc.c;h=b6821d447c92183101086cb67099b2f4804293de;hb=HEAD#l2905
+
+        Workaround -movflags use_metadata_tags found here: https://superuser.com/a/1208277      
+        
+        Ffmpeg premapped id3 tags: https://wiki.multimedia.cx/index.php/FFmpeg_Metadata
+      */
+
+      const ffmpegOptions = ['-c copy', '-map_metadata 1', `-metadata track=${audioFile.index}`, '-write_id3v2 1', '-movflags use_metadata_tags']
+      var workerData = {
+        inputs: ffmpegInputs,
+        options: ffmpegOptions,
+        outputOptions: isM4b ? ['-f mp4'] : [],
+        output: outputPath,
+      }
+      var workerPath = Path.join(global.appRoot, 'server/utils/downloadWorker.js')
+      var worker = new workerThreads.Worker(workerPath, { workerData })
+
+      worker.on('message', async (message) => {
+        if (message != null && typeof message === 'object') {
+          if (message.type === 'RESULT') {
+            Logger.debug(message)
+
+            if (message.success) {
+              Logger.debug(`[AudioFileMetadataManager] Metadata encode SUCCESS for "${audioFile.metadata.filename}"`)
+
+              await filePerms.setDefault(outputPath, true)
+
+              fs.move(outputPath, inputPath, { overwrite: true }).then(() => {
+                Logger.debug(`[AudioFileMetadataManager] Audio file replaced successfully "${inputPath}"`)
+
+                resultPayload.success = true
+                this.emitter('audiofile_metadata_finished', resultPayload)
+                resolve(resultPayload)
+              }).catch((error) => {
+                Logger.error(`[AudioFileMetadataManager] Audio file failed to move "${inputPath}"`, error)
+                resultPayload.success = false
+                this.emitter('audiofile_metadata_finished', resultPayload)
+                resolve(resultPayload)
+              })
+            } else {
+              Logger.debug(`[AudioFileMetadataManager] Metadata encode FAILED for "${audioFile.metadata.filename}"`)
+
+              resultPayload.success = false
+              this.emitter('audiofile_metadata_finished', resultPayload)
+              resolve(resultPayload)
+            }
+          } else if (message.type === 'FFMPEG') {
+            if (Logger[message.level]) {
+              Logger[message.level](message.log)
+            }
+          }
+        } else {
+          Logger.error('Invalid worker message', message)
+        }
+      })
+    })
+  }
+}
+module.exports = AudioMetadataMangaer