Fix transcoding errors in readonly docker containers

[gramakri]

ffmpeg seems to create some temporary files in the cwd. When PeerTube
is run in a read-only docker container, this causes all transcoding
to fail. As a workaround, we set the cwd to the configured tmp dir.

[gramakri]

The exact error is in the forum post here - https://forum.cloudron.io/topic/3414/transcode-after-import-fails (EROFS)

error[15-10-2020 09:32:42] Error in transcoding job.

{
  "stdout": "",
  "stderr": "ffmpeg version 3.4.8-0ubuntu0.2 Copyright (c) 2000-2020 the FFmpeg developers\n  built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)\n  configuration: --prefix=/usr --extra-version=0ubuntu0.2 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared\n  libavutil      55. 78.100 / 55. 78.100\n  libavcodec     57.107.100 / 57.107.100\n  libavformat    57. 83.100 / 57. 83.100\n  libavdevice    57. 10.100 / 57. 10.100\n  libavfilter     6.107.100 /  6.107.100\n  libavresample   3.  7.  0 /  3.  7.  0\n  libswscale      4.  8.100 /  4.  8.100\n  libswresample   2.  9.100 /  2.  9.100\n  libpostproc    54.  7.100 / 54.  7.100\nInput #0, mov,mp4,m4a,3gp,3g2,mj2, from '/app/data/storage/videos/881f46cb-4afb-4977-9fe2-7fe580d20fc0-480.mp4':\n  Metadata:\n    major_brand     : isom\n    minor_version   : 512\n    compatible_brands: isomiso2avc1mp41\n    encoder         : Lavf57.83.100\n  Duration: 00:00:27.05, start: 0.000000, bitrate: 799 kb/s\n    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 854x480 [SAR 1:1 DAR 427:240], 669 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc (default)\n    Metadata:\n      handler_name    : VideoHandler\n    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 125 kb/s (default)\n    Metadata:\n      handler_name    : SoundHandler\n[hls @ 0x55601c225e40] Opening 'init.mp4' for writing\n[hls @ 0x55601c225e40] Failed to open segment '/app/data/storage/streaming-playlists/hls/881f46cb-4afb-4977-9fe2-7fe580d20fc0/881f46cb-4afb-4977-9fe2-7fe580d20fc0-480-fragmented.mp4'\nCould not write header for output file #0 (incorrect codec parameters ?): Read-only file system\nStream mapping:\n  Stream #0:0 -> #0:0 (copy)\n  Stream #0:1 -> #0:1 (copy)\n    Last message repeated 1 times\n"
}

error[15-10-2020 09:32:42] Cannot execute job 7 in queue video-transcoding.

{
  "payload": {
    "type": "hls",
    "videoUUID": "881f46cb-4afb-4977-9fe2-7fe580d20fc0",
    "resolution": 480,
    "copyCodecs": true
  },
  "err": {
    "stack": "Error: ffmpeg exited with code 1: \n    at ChildProcess.<anonymous> (/app/code/server/node_modules/fluent-ffmpeg/lib/processor.js:182:22)\n    at ChildProcess.emit (events.js:310:20)\n    at Process.ChildProcess._handle.onexit (internal/child_process.js:275:12)",
    "message": "ffmpeg exited with code 1: "
  }
}

error[15-10-2020 09:32:43] Error in transcoding job.

{
  "stdout": "",
  "stderr": "ffmpeg version 3.4.8-0ubuntu0.2 Copyright (c) 2000-2020 the FFmpeg developers\n  built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)\n  configuration: --prefix=/usr --extra-version=0ubuntu0.2 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared\n  libavutil      55. 78.100 / 55. 78.100\n  libavcodec     57.107.100 / 57.107.100\n  libavformat    57. 83.100 / 57. 83.100\n  libavdevice    57. 10.100 / 57. 10.100\n  libavfilter     6.107.100 /  6.107.100\n  libavresample   3.  7.  0 /  3.  7.  0\n  libswscale      4.  8.100 /  4.  8.100\n  libswresample   2.  9.100 /  2.  9.100\n  libpostproc    54.  7.100 / 54.  7.100\nInput #0, mov,mp4,m4a,3gp,3g2,mj2, from '/app/data/storage/videos/881f46cb-4afb-4977-9fe2-7fe580d20fc0-480.mp4':\n  Metadata:\n    major_brand     : isom\n    minor_version   : 512\n    compatible_brands: isomiso2avc1mp41\n    encoder         : Lavf57.83.100\n  Duration: 00:00:27.05, start: 0.000000, bitrate: 799 kb/s\n    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 854x480 [SAR 1:1 DAR 427:240], 669 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc (default)\n    Metadata:\n      handler_name    : VideoHandler\n    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 125 kb/s (default)\n    Metadata:\n      handler_name    : SoundHandler\nStream mapping:\n  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))\n  Stream #0:1 -> #0:1 (aac (native) -> aac (native))\nPress [q] to stop, [?] for help\n[libx264 @ 0x560188acf240] using SAR=1281/1280\n[libx264 @ 0x560188acf240] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2\n[libx264 @ 0x560188acf240] profile High, level 3.1\n[libx264 @ 0x560188acf240] 264 - core 152 r2854 e9a5903 - H.264/MPEG-4 AVC codec - Copyleft 2003-2017 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=4 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=16 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=50 keyint_min=5 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=728 vbv_bufsize=1456 crf_max=0.0 nal_hrd=none filler=0 ip_ratio=1.40 aq=1:1.00\n[hls @ 0x560188aca9a0] Opening 'init.mp4' for writing\n[hls @ 0x560188aca9a0] Failed to open segment '/app/data/storage/streaming-playlists/hls/881f46cb-4afb-4977-9fe2-7fe580d20fc0/881f46cb-4afb-4977-9fe2-7fe580d20fc0-360-fragmented.mp4'\nCould not write header for output file #0 (incorrect codec parameters ?): Read-only file system\nError initializing output stream 0:0 -- \n[aac @ 0x560188af2620] Qavg: 13786.650\n[aac @ 0x560188af2620] 2 frames left in the queue on closing\nConversion failed!\n"
}

error[15-10-2020 09:32:43] Cannot execute job 8 in queue video-transcoding.

{
  "payload": {
    "type": "hls",
    "videoUUID": "881f46cb-4afb-4977-9fe2-7fe580d20fc0",
    "resolution": 360,
    "isPortraitMode": false,
    "copyCodecs": false
  },
  "err": {
    "stack": "Error: ffmpeg exited with code 1: Conversion failed!\n\n    at ChildProcess.<anonymous> (/app/code/server/node_modules/fluent-ffmpeg/lib/processor.js:182:22)\n    at ChildProcess.emit (events.js:310:20)\n    at Process.ChildProcess._handle.onexit (internal/child_process.js:275:12)",
    "message": "ffmpeg exited with code 1: Conversion failed!\n"
  }
}

[gramakri]

I think this fails because we have to update the @types/fluent-ffmpeg to 2.1.14 (DefinitelyTyped/DefinitelyTyped#48421)

[Chocobozzz]

Thanks @gramakri