Add `--print playlist:` to print fields per playlist

README.md

@@ -662,10 +662,12 @@ You can also fork the project on github and run your fork's [build workflow](.gi
                                      formats are found (default)
     --skip-download                  Do not download the video but write all
                                      related files (Alias: --no-download)
-    -O, --print TEMPLATE             Quiet, but print the given fields for each
-                                     video. Simulate unless --no-simulate is
-                                     used. Either a field name or same syntax as
-                                     the output template can be used
+    -O, --print [WHEN:]TEMPLATE      Field name or output template to print to
+                                     screen per video. Prefix the template with
+                                     "playlist:" to print it once per playlist
+                                     instead. Implies --quiet and --simulate
+                                     (unless --no-simulate is used). This option
+                                     can be used multiple times
     -j, --dump-json                  Quiet, but print JSON information for each
                                      video. Simulate unless --no-simulate is
                                      used. See "OUTPUT TEMPLATE" for a

yt_dlp/YoutubeDL.py

@@ -199,7 +199,9 @@ class YoutubeDL(object):
     verbose:           Print additional info to stdout.
     quiet:             Do not print messages to stdout.
     no_warnings:       Do not print out anything for warnings.
-    forceprint:        A list of templates to force print
+    forceprint:        A dict with keys video/playlist mapped to
+                       a list of templates to force print to stdout
+                       For compatibility, a single list is also accepted
     forceurl:          Force printing final URL. (Deprecated)
     forcetitle:        Force printing title. (Deprecated)
     forceid:           Force printing ID. (Deprecated)
@@ -585,6 +587,11 @@ class YoutubeDL(object):
         else:
             self.params['nooverwrites'] = not self.params['overwrites']
 
+        # Compatibility with older syntax
+        params.setdefault('forceprint', {})
+        if not isinstance(params['forceprint'], dict):
+            params['forceprint'] = {'video': params['forceprint']}
+
         if params.get('bidi_workaround', False):
             try:
                 import pty
@@ -1755,6 +1762,9 @@ class YoutubeDL(object):
                 'updated playlist', ie_result,
                 self.prepare_filename(ie_copy, 'pl_infojson'), overwrite=True) is None:
             return
+
+        for tmpl in self.params['forceprint'].get('playlist', []):
+            self._forceprint(tmpl, ie_result)
         self.to_screen('[download] Finished downloading playlist: %s' % playlist)
         return ie_result
 
@@ -2626,6 +2636,14 @@ class YoutubeDL(object):
             subs[lang] = f
         return subs
 
+    def _forceprint(self, tmpl, info_dict):
+        mobj = re.match(r'\w+(=?)$', tmpl)
+        if mobj and mobj.group(1):
+            tmpl = f'{tmpl[:-1]} = %({tmpl[:-1]})s'
+        elif mobj:
+            tmpl = '%({})s'.format(tmpl)
+        self.to_stdout(self.evaluate_outtmpl(tmpl, info_dict))
+
     def __forced_printings(self, info_dict, filename, incomplete):
         def print_mandatory(field, actual_field=None):
             if actual_field is None:
@@ -2648,15 +2666,10 @@ class YoutubeDL(object):
         elif 'url' in info_dict:
             info_dict['urls'] = info_dict['url'] + info_dict.get('play_path', '')
 
-        if self.params.get('forceprint') or self.params.get('forcejson'):
+        if self.params['forceprint'].get('video') or self.params.get('forcejson'):
             self.post_extract(info_dict)
-        for tmpl in self.params.get('forceprint', []):
-            mobj = re.match(r'\w+(=?)$', tmpl)
-            if mobj and mobj.group(1):
-                tmpl = f'{tmpl[:-1]} = %({tmpl[:-1]})s'
-            elif mobj:
-                tmpl = '%({})s'.format(tmpl)
-            self.to_stdout(self.evaluate_outtmpl(tmpl, info_dict))
+        for tmpl in self.params['forceprint'].get('video', []):
+            self._forceprint(tmpl, info_dict)
 
         print_mandatory('title')
         print_mandatory('id')

yt_dlp/__init__.py

@@ -351,9 +351,9 @@ def _real_main(argv=None):
 
     for k, tmpl in opts.outtmpl.items():
         validate_outtmpl(tmpl, f'{k} output template')
-    opts.forceprint = opts.forceprint or []
-    for tmpl in opts.forceprint or []:
-        validate_outtmpl(tmpl, 'print template')
+    for type_, tmpl_list in opts.forceprint.items():
+        for tmpl in tmpl_list:
+            validate_outtmpl(tmpl, f'{type_} print template')
     validate_outtmpl(opts.sponsorblock_chapter_title, 'SponsorBlock chapter title')
     for k, tmpl in opts.progress_template.items():
         k = f'{k[:-6]} console title' if '-title' in k else f'{k} progress'
@@ -395,7 +395,10 @@ def _real_main(argv=None):
         opts.parse_metadata.append('title:%s' % opts.metafromtitle)
     opts.parse_metadata = list(itertools.chain(*map(metadataparser_actions, opts.parse_metadata)))
 
-    any_getting = opts.forceprint or opts.geturl or opts.gettitle or opts.getid or opts.getthumbnail or opts.getdescription or opts.getfilename or opts.getformat or opts.getduration or opts.dumpjson or opts.dump_single_json
+    any_getting = (any(opts.forceprint.values()) or opts.dumpjson or opts.dump_single_json
+                   or opts.geturl or opts.gettitle or opts.getid or opts.getthumbnail
+                   or opts.getdescription or opts.getfilename or opts.getformat or opts.getduration)
+
     any_printing = opts.print_json
     download_archive_fn = expand_path(opts.download_archive) if opts.download_archive is not None else opts.download_archive
 

yt_dlp/options.py

@@ -152,9 +152,9 @@ def parseOpts(overrideArguments=None):
     def _dict_from_options_callback(
             option, opt_str, value, parser,
             allowed_keys=r'[\w-]+', delimiter=':', default_key=None, process=None, multiple_keys=True,
-            process_key=str.lower):
+            process_key=str.lower, append=False):
 
-        out_dict = getattr(parser.values, option.dest)
+        out_dict = dict(getattr(parser.values, option.dest))
         if multiple_keys:
             allowed_keys = r'(%s)(,(%s))*' % (allowed_keys, allowed_keys)
         mobj = re.match(r'(?i)(?P<keys>%s)%s(?P<val>.*)$' % (allowed_keys, delimiter), value)
@@ -171,7 +171,8 @@ def parseOpts(overrideArguments=None):
         except Exception as err:
             raise optparse.OptionValueError(f'wrong {opt_str} formatting; {err}')
         for key in keys:
-            out_dict[key] = val
+            out_dict[key] = out_dict.get(key, []) + [val] if append else val
+        setattr(parser.values, option.dest, out_dict)
 
     # No need to wrap help messages if we're on a wide console
     columns = compat_get_terminal_size().columns
@@ -882,10 +883,17 @@ def parseOpts(overrideArguments=None):
         help='Do not download the video but write all related files (Alias: --no-download)')
     verbosity.add_option(
         '-O', '--print',
-        metavar='TEMPLATE', action='append', dest='forceprint',
-        help=(
-            'Quiet, but print the given fields for each video. Simulate unless --no-simulate is used. '
-            'Either a field name or same syntax as the output template can be used'))
+        metavar='[WHEN:]TEMPLATE', dest='forceprint', default={}, type='str',
+        action='callback', callback=_dict_from_options_callback,
+        callback_kwargs={
+            'allowed_keys': 'video|playlist',
+            'default_key': 'video',
+            'multiple_keys': False,
+            'append': True,
+        }, help=(
+            'Field name or output template to print to screen per video. '
+            'Prefix the template with "playlist:" to print it once per playlist instead. '
+            'Implies --quiet and --simulate (unless --no-simulate is used). This option can be used multiple times'))
     verbosity.add_option(
         '-g', '--get-url',
         action='store_true', dest='geturl', default=False,