how do you set variables which were parsed by youtube-dl to external ones belonging to a process started by a script?

[Albretch]

It seems my question would be more of a RFE, but, most probably other youtube-dl users have those kinds of needs as well.

youtube-dl internally parses a number of variables defined in the output template:

https://github.com/rg3/youtube-dl/blob/master/README.md#output-template

which can be used within the same Python process, but how do you set variables in the running process? I fancy something like:

--set-xparams={$PL:%(playlist)s, $SZ:%(filesize)s}

PL=""
SZ=""

time(python youtube-dl --simulate --verbose --no-progress --user-agent "${_UA}"
--output "${ODIR}/%(uploader)s/%(title)s""%(id)s.%(ext)s" " -- " "PL27BCE863B6A864E3"
--set-xparams={$PL:%(playlist)s, $SZ:%(totalplsize)s}
) >> "$PL.log" 2>&1

echo " $PL: |$PL|, $SZ: |$SZ|"

where "totalplsize" would be the size of all files belonging to a playlist (if unkown -1 shold be the value)

or, which kinds of tricks do people use to use youtube-dl parsed data in external processes?

$ youtube-dl --version
2017.10.15.1

$ youtube-dl --help | grep "set|get|extern|pars|param"
--xattr-set-filesize Set file xattribute ytdl.filesize with expected file size (experimental)
--external-downloader COMMAND Use the specified external downloader. Currently supports aria2c,avconv,axel,curl,ffmpeg,httpie,wget
--external-downloader-args ARGS Give these arguments to the external downloader
--no-mtime Do not use the Last-modified header to set the file modification time
-g, --get-url Simulate, quiet but print URL
-e, --get-title Simulate, quiet but print title
--get-id Simulate, quiet but print id
--get-thumbnail Simulate, quiet but print thumbnail URL
--get-description Simulate, quiet but print video description
--get-duration Simulate, quiet but print video length
--get-filename Simulate, quiet but print output filename
--get-format Simulate, quiet but print output format
expression with named capture groups may also be used. The parsed parameters replace existing values. Example: --metadata-from-
~
lbrtchx

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Add the -v flag to your command line you run youtube-dl with (youtube-dl -v <your command line>), copy the whole output and insert it here. It should look similar to one below (replace it with your log inserted between triple ```):

[debug] System config: []
[debug] User config: []
[debug] Command-line args: [u'-v', u'http://www.youtube.com/watch?v=BaW_jenozKcj']
[debug] Encodings: locale cp1251, fs mbcs, out cp866, pref cp1251
[debug] youtube-dl version 2017.10.15.1
[debug] Python version 2.7.11 - Windows-2003Server-5.2.3790-SP2
[debug] exe versions: ffmpeg N-75573-g1d0487f, ffprobe N-75573-g1d0487f, rtmpdump 2.4
[debug] Proxy map: {}
...
<end of log>

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If the purpose of this issue is a site support request please provide all kinds of example URLs support for which should be included (replace following example URLs by yours):

• Single video: https://www.youtube.com/watch?v=BaW_jenozKc
• Single video: https://youtu.be/BaW_jenozKc
• Playlist: https://www.youtube.com/playlist?list=PL4lCao7KL_QFVb7Iudeipvc2BCavECqzc

Note that youtube-dl does not support sites dedicated to copyright infringement. In order for site support request to be accepted all provided example URLs should not violate any copyrights.

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[dstftw]

Output template exists for completely different purpose. If you want to extract data from youtube-dl parse JSON output obtained with --dump-json.