Repository: yt-dlp/yt-dlp
File: yt_dlp/extractor/facebook.py (Python)

Code before:
            check_req = sanitized_Request(self._CHECKPOINT_URL, urlencode_postdata(check_form))
            check_req.add_header('Content-Type', 'application/x-www-form-urlencoded')
            check_response = self._download_webpage(check_req, None,
                                                    note='Confirming login')
            if re.search(r'id="checkpointSubmitButton"', check_response) is not None:
                self.report_warning('Unable to confirm login, you have to login in your browser and authorize the login.')
        except network_exceptions as err:
            self.report_warning('unable to log in: %s' % error_to_compat_str(err))
            return

    def _extract_from_url(self, url, video_id):
        webpage = self._download_webpage(
            url.replace('://m.facebook.com/', '://www.facebook.com/'), video_id)

        def extract_metadata(webpage):
            post_data = [self._parse_json(j, video_id, fatal=False) for j in re.findall(
                r'handleWithCustomApplyEach\(\s*ScheduledApplyEach\s*,\s*(\{.+?\})\s*\);', webpage)]
            post = traverse_obj(post_data, (
                ..., 'require', ..., ..., ..., '__bbox', 'result', 'data'), expected_type=dict) or []
            media = traverse_obj(post, (..., 'attachments', ..., lambda k, v: (
                k == 'media' and str(v['id']) == video_id and v['__typename'] == 'Video')), expected_type=dict)
            title = get_first(media, ('title', 'text'))
            description = get_first(media, ('creation_story', 'comet_sections', 'message', 'story', 'message', 'text'))
            uploader_data = (
                get_first(media, ('owner', {dict}))
                or get_first(post, (..., 'video', lambda k, v: k == 'owner' and v.get('name')), expected_type=dict)
                or get_first(post, ('node', 'actors', ..., {dict}))
                or {})

            page_title = title or self._html_search_regex((
                r'<h2\s+[^>]*class="uiHeaderTitle"[^>]*>(?P<content>[^<]*)</h2>',
                r'(?s)<span class="fbPhotosPhotoCaption".*?id="fbPhotoPageCaption"><span class="hasCaption">(?P<content>.*?)</span>',
                self._meta_regex('og:title'), self._meta_regex('twitter:title'), r'<title>(?P<content>.+?)</title>'
            ), webpage, 'title', default=None, group='content')
            description = description or self._html_search_meta(
                ['description', 'og:description', 'twitter:description'],
                webpage, 'description', default=None)
            uploader = uploader_data.get('name') or (
                clean_html(get_element_by_id('fbPhotoPageAuthorName', webpage))
                or self._search_regex(
                    (r'ownerName\s*:\s*"([^"]+)"', *self._og_regexes('title')), webpage, 'uploader', fatal=False))

            timestamp = int_or_none(self._search_regex(
                r'<abbr[^>]+data-utime=["\'](\d+)', webpage,
                'timestamp', default=None))
            thumbnail = self._html_search_meta(
                ['og:image', 'twitter:image'], webpage, 'thumbnail', default=None)
            # some webpages contain unretrievable thumbnail urls
            # like https://lookaside.fbsbx.com/lookaside/crawler/media/?media_id=10155168902769113&get_thumbnail=1
            # in https://www.facebook.com/yaroslav.korpan/videos/1417995061575415/
            if thumbnail and not re.search(r'\.(?:jpg|png)', thumbnail):

Review comment (suggestion):
Filtering in traversal is non-fatal, `.get` is unnecessary
and since we are already filtering for dict keys/values, `expected_type=dict` is not needed:
```suggestion
                or get_first(post, (..., 'video', lambda k, v: k == 'owner' and v['name']))
```
&nbsp;
but now that I think about it, this could probably be simplified to:
```suggestion
                or get_first(post, (..., 'video', 'owner', {dict}))
```
What do you think? Or are there `owner` objects without a `name` key that we specifically need to avoid?

If the latter suggestion works, it could probably be moved up a line

Code after:
            check_req = sanitized_Request(self._CHECKPOINT_URL, urlencode_postdata(check_form))
            check_req.add_header('Content-Type', 'application/x-www-form-urlencoded')
            check_response = self._download_webpage(check_req, None,
                                                    note='Confirming login')
            if re.search(r'id="checkpointSubmitButton"', check_response) is not None:
                self.report_warning('Unable to confirm login, you have to login in your browser and authorize the login.')
        except network_exceptions as err:
            self.report_warning('unable to log in: %s' % error_to_compat_str(err))
            return

    def _extract_from_url(self, url, video_id):
        webpage = self._download_webpage(
            url.replace('://m.facebook.com/', '://www.facebook.com/'), video_id)

        def extract_metadata(webpage):
            post_data = [self._parse_json(j, video_id, fatal=False) for j in re.findall(
                r'handleWithCustomApplyEach\(\s*ScheduledApplyEach\s*,\s*(\{.+?\})\s*\);', webpage)]
            post = traverse_obj(post_data, (
                ..., 'require', ..., ..., ..., '__bbox', 'result', 'data'), expected_type=dict) or []
            media = traverse_obj(post, (..., 'attachments', ..., lambda k, v: (
                k == 'media' and str(v['id']) == video_id and v['__typename'] == 'Video')), expected_type=dict)
            title = get_first(media, ('title', 'text'))
            description = get_first(media, ('creation_story', 'comet_sections', 'message', 'story', 'message', 'text'))
            uploader_data = (
                get_first(media, ('owner', {dict}))
                or get_first(post, (..., 'video', lambda k, v: k == 'owner' and v['name']))
                or get_first(post, ('node', 'actors', ..., {dict})) or {})

            page_title = title or self._html_search_regex((
                r'<h2\s+[^>]*class="uiHeaderTitle"[^>]*>(?P<content>[^<]*)</h2>',
                r'(?s)<span class="fbPhotosPhotoCaption".*?id="fbPhotoPageCaption"><span class="hasCaption">(?P<content>.*?)</span>',
                self._meta_regex('og:title'), self._meta_regex('twitter:title'), r'<title>(?P<content>.+?)</title>'
            ), webpage, 'title', default=None, group='content')
            description = description or self._html_search_meta(
                ['description', 'og:description', 'twitter:description'],
                webpage, 'description', default=None)
            uploader = uploader_data.get('name') or (
                clean_html(get_element_by_id('fbPhotoPageAuthorName', webpage))
                or self._search_regex(
                    (r'ownerName\s*:\s*"([^"]+)"', *self._og_regexes('title')), webpage, 'uploader', fatal=False))

            timestamp = int_or_none(self._search_regex(
                r'<abbr[^>]+data-utime=["\'](\d+)', webpage,
                'timestamp', default=None))
            thumbnail = self._html_search_meta(
                ['og:image', 'twitter:image'], webpage, 'thumbnail', default=None)
            # some webpages contain unretrievable thumbnail urls
            # like https://lookaside.fbsbx.com/lookaside/crawler/media/?media_id=10155168902769113&get_thumbnail=1
            # in https://www.facebook.com/yaroslav.korpan/videos/1417995061575415/
            if thumbnail and not re.search(r'\.(?:jpg|png)', thumbnail):
                thumbnail = None