Add video file metadata to download modal, via ffprobe (#2411)

* Add video file metadata via ffprobe

* Federate video file metadata

* Add tests for file metadata generation

* Complete tests for videoFile metadata federation

* Lint migration and video-file for metadata

* Objectify metadata from getter in ffmpeg-utils

* Add metadataUrl to all videoFiles

* Simplify metadata API middleware

* Load playlist in videoFile when requesting metadata

1 files changed, 13 insertions, 20 deletions

diff --git a/server/helpers/ffmpeg-utils.ts b/server/helpers/ffmpeg-utils.ts
index 084516e55..5ee295635 100644
--- a/server/helpers/ffmpeg-utils.ts
+++ b/server/helpers/ffmpeg-utils.ts
@@ -7,6 +7,7 @@ import { logger } from './logger'
 import { checkFFmpegEncoders } from '../initializers/checker-before-init'
 import { readFile, remove, writeFile } from 'fs-extra'
 import { CONFIG } from '../initializers/config'
+import { VideoFileMetadata } from '@shared/models/videos/video-file-metadata'
 
 /**
  * A toolbox to play with audio
@@ -169,24 +170,26 @@ async function getVideoFileFPS (path: string) {
   return 0
 }
 
-async function getVideoFileBitrate (path: string) {
-  return new Promise<number>((res, rej) => {
+async function getMetadataFromFile<T> (path: string, cb = metadata => metadata) {
+  return new Promise<T>((res, rej) => {
     ffmpeg.ffprobe(path, (err, metadata) => {
       if (err) return rej(err)
 
-      return res(metadata.format.bit_rate)
+      return res(cb(new VideoFileMetadata(metadata)))
     })
   })
 }
 
+async function getVideoFileBitrate (path: string) {
+  return getMetadataFromFile<number>(path, metadata => metadata.format.bit_rate)
+}
+
 function getDurationFromVideoFile (path: string) {
-  return new Promise<number>((res, rej) => {
-    ffmpeg.ffprobe(path, (err, metadata) => {
-      if (err) return rej(err)
+  return getMetadataFromFile<number>(path, metadata => Math.floor(metadata.format.duration))
+}
 
-      return res(Math.floor(metadata.format.duration))
-    })
-  })
+function getVideoStreamFromFile (path: string) {
+  return getMetadataFromFile<any>(path, metadata => metadata.streams.find(s => s.codec_type === 'video') || null)
 }
 
 async function generateImageFromVideoFile (fromPath: string, folder: string, imageName: string, size: { width: number, height: number }) {
@@ -341,6 +344,7 @@ export {
   getAudioStreamCodec,
   getVideoStreamSize,
   getVideoFileResolution,
+  getMetadataFromFile,
   getDurationFromVideoFile,
   generateImageFromVideoFile,
   TranscodeOptions,
@@ -450,17 +454,6 @@ async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
   await writeFile(options.outputPath, newContent)
 }
 
-function getVideoStreamFromFile (path: string) {
-  return new Promise<any>((res, rej) => {
-    ffmpeg.ffprobe(path, (err, metadata) => {
-      if (err) return rej(err)
-
-      const videoStream = metadata.streams.find(s => s.codec_type === 'video')
-      return res(videoStream || null)
-    })
-  })
-}
-
 /**
  * A slightly customised version of the 'veryfast' x264 preset
  *