youtube: -j --flat-playlist with channel different in CLI than return from API call

[patrickscottbest]

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[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: ['--flat-playlist', '-j', '-v', 'https://www.youtube.com/channel/UC6RNSPFcqY4BblL2Jg9SUtw']
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2018.11.07
[debug] Python version 3.6.5 (CPython) - Linux-3.10.0-862.14.4.el7.x86_64-x86_64-with-centos-7.5.1804-Core
[debug] exe versions: ffmpeg 2.8.15, ffprobe 2.8.15
[debug] Proxy map: {}
{"_type": "url", "url": "IaNEfhPmhPM", "ie_key": "Youtube", "id": "IaNEfhPmhPM", "title": "Rona in Aurora - the death of a big box"}
{"_type": "url", "url": "JN-2vTf8-WM", "ie_key": "Youtube", "id": "JN-2vTf8-WM", "title": "RealWorldNumbers - How to Test a Raspberry Pi Powered by Alkaline AA Batteries - After Poweroff"}
{"_type": "url", "url": "NmQmM36ja3o", "ie_key": "Youtube", "id": "NmQmM36ja3o", "title": "RealWorldNumbers - How to Test a Raspberry Pi Powered by Alkaline AA Batteries - During the Test"}
{"_type": "url", "url": "MsrgW1Rdlso", "ie_key": "Youtube", "id": "MsrgW1Rdlso", "title": "Raspberry Pi powered by AA batteries direct"}
(bestpa) [bestpa@oraclevm vidbackup]$ 
---


Playlist: https://www.youtube.com/channel/UC6RNSPFcqY4BblL2Jg9SUtw


---

### Description of your *issue*, suggested solution and other information

I've got a problem whereby when I call  youtube-dl  from the CLI with "-j --flat-playlist" I get a list of videos, but when i make the same call using  the same arguments from an imported instance of the python library, it only presents a single object (instead of iterating through the list of videos).

I've opened up a discussion on stackoverflow, but no real explanation for the behaviour.
https://stackoverflow.com/questions/53288922/youtube-dl-dump-json-returning-different-extractor-output-for-playlist-when-ca

Here's the python code: 

    import youtube_dl
    ydl_opts = {
        'extract_flat': True, ## --flat-playlist according to options.py
         'dumpjson': True, ## lower -j
         #'dump_single_json': True, ## UPPER -J
    }
    with youtube_dl.YoutubeDL(ydl_opts) as ydl:
        object = ydl.extract_info(providedURL, download=False)
        print (object)
        print len(object)
  print (youtube_dl.version.unicode_literals)

Her'es the output

[youtube:channel] UC6RNSPFcqY4BblL2Jg9SUtw: Downloading channel page
{'_type': 'url', 'url': 'https://www.youtube.com/playlist?list=UU6RNSPFcqY4BblL2Jg9SUtw', 'ie_key': 'YoutubePlaylist', 'extractor': 'youtube:channel', 'webpage_url': 'https://www.youtube.com/channel/UC6RNSPFcqY4BblL2Jg9SUtw', 'webpage_url_basename': 'UC6RNSPFcqY4BblL2Jg9SUtw', 'extractor_key': 'YoutubeChannel'}

7

Long shot, but wonder if this could be resurgence or related to a closed issue from 2015.  https://github.com/rg3/youtube-dl/issues/4971

I'd like to know more about the procedural different between the cli and using the python .extract_info method.  Is this because of the nature of the interactive shell when using the CLI method?

sorry my markup is terrible on this report.  I hope that you guys can read past it.  Late. Tired. Thanks.

[dstftw]

1. Have you actually read the doc? You're getting exactly what requested.

    extract_flat:      Do not resolve URLs, return the immediate result.
                       Pass in 'in_playlist' to only show this behavior for
                       playlist items.

Pass in 'in_playlist' to only show this behavior for playlist items.

Passing True will forbid any recursive resolving including playlists (will forbid resolving channel to playlist url delegate transition in your case). in_playlist will forbid resolving but only at playlist level (allowing aforementioned transition), that produces info dict with the same list of videos under entries.
2. --dump-* options don't return anything, they are verbose options for printing to stdout. dump* API options have no effect on extract_info.