[extractor/common] Extend _extract_akamai_formats to also extract subtitle tracks

yt_dlp/extractor/common.py

@@ -3023,7 +3023,16 @@ class InfoExtractor(object):
                 entries.append(media_info)
         return entries
 
-    def _extract_akamai_formats(self, manifest_url, video_id, hosts={}):
+    def _extract_akamai_formats(self, *args, **kwargs):
+        fmts, subs = self._extract_akamai_formats_and_subtitles(*args, **kwargs)
+        if subs:
+            self.report_warning(bug_reports_message(
+                "Ignoring subtitle tracks found in the manifests; "
+                "if any subtitle tracks are missing,"
+            ))
+        return fmts
+
+    def _extract_akamai_formats_and_subtitles(self, manifest_url, video_id, hosts={}):
         signed = 'hdnea=' in manifest_url
         if not signed:
             # https://learn.akamai.com/en-us/webhelp/media-services-on-demand/stream-packaging-user-guide/GUID-BE6C0F73-1E06-483B-B0EA-57984B91B7F9.html
@@ -3032,6 +3041,7 @@ class InfoExtractor(object):
                 '', manifest_url).strip('?')
 
         formats = []
+        subtitles = {}
 
         hdcore_sign = 'hdcore=3.7.0'
         f4m_url = re.sub(r'(https?://[^/]+)/i/', r'\1/z/', manifest_url).replace('/master.m3u8', '/manifest.f4m')
@@ -3050,10 +3060,11 @@ class InfoExtractor(object):
         hls_host = hosts.get('hls')
         if hls_host:
             m3u8_url = re.sub(r'(https?://)[^/]+', r'\1' + hls_host, m3u8_url)
-        m3u8_formats = self._extract_m3u8_formats(
+        m3u8_formats, m3u8_subtitles = self._extract_m3u8_formats_and_subtitles(
             m3u8_url, video_id, 'mp4', 'm3u8_native',
             m3u8_id='hls', fatal=False)
         formats.extend(m3u8_formats)
+        subtitles = self._merge_subtitles(subtitles, m3u8_subtitles)
 
         http_host = hosts.get('http')
         if http_host and m3u8_formats and not signed:
@@ -3077,7 +3088,7 @@ class InfoExtractor(object):
                             formats.append(http_f)
                         i += 1
 
-        return formats
+        return formats, subtitles
 
     def _extract_wowza_formats(self, url, video_id, m3u8_entry_protocol='m3u8_native', skip_protocols=[]):
         query = compat_urlparse.urlparse(url).query