[cleanup] Refactor some code

[yt-dlp.git] / yt_dlp / downloader / dash.py

diff --git a/yt_dlp/downloader/dash.py b/yt_dlp/downloader/dash.py
index 6eae5bf0ae38ea90f56b8dd28565960961666f0c..ccc41e1588c4edc5c180424a6d37be74289a88cc 100644 (file)
--- a/yt_dlp/downloader/dash.py
+++ b/yt_dlp/downloader/dash.py
@@ -1,29 +1,28 @@
 from __future__ import unicode_literals
 
-from ..downloader import _get_real_downloader
+from ..downloader import get_suitable_downloader
 from .fragment import FragmentFD
 
-from ..compat import compat_urllib_error
-from ..utils import (
-    DownloadError,
-    urljoin,
-)
+from ..utils import urljoin
 
 
 class DashSegmentsFD(FragmentFD):
     """
     Download segments in a DASH manifest. External downloaders can take over
-    the fragment downloads by supporting the 'frag_urls' protocol
+    the fragment downloads by supporting the 'dash_frag_urls' protocol
     """
 
     FD_NAME = 'dashsegments'
 
     def real_download(self, filename, info_dict):
+        if info_dict.get('is_live'):
+            self.report_error('Live DASH videos are not supported')
+
         fragment_base_url = info_dict.get('fragment_base_url')
         fragments = info_dict['fragments'][:1] if self.params.get(
             'test', False) else info_dict['fragments']
 
-        real_downloader = _get_real_downloader(info_dict, 'frag_urls', self.params, None)
+        real_downloader = get_suitable_downloader(info_dict, self.params, None, protocol='dash_frag_urls')
 
         ctx = {
             'filename': filename,
@@ -33,10 +32,7 @@ def real_download(self, filename, info_dict):
         if real_downloader:
             self._prepare_external_frag_download(ctx)
         else:
-            self._prepare_and_start_frag_download(ctx)
-
-        fragment_retries = self.params.get('fragment_retries', 0)
-        skip_unavailable_fragments = self.params.get('skip_unavailable_fragments', True)
+            self._prepare_and_start_frag_download(ctx, info_dict)
 
         fragments_to_download = []
         frag_index = 0
@@ -49,58 +45,18 @@ def real_download(self, filename, info_dict):
                 assert fragment_base_url
                 fragment_url = urljoin(fragment_base_url, fragment['path'])
 
-            if real_downloader:
-                fragments_to_download.append({
-                    'url': fragment_url,
-                })
-                continue
-
-            # In DASH, the first segment contains necessary headers to
-            # generate a valid MP4 file, so always abort for the first segment
-            fatal = i == 0 or not skip_unavailable_fragments
-            count = 0
-            while count <= fragment_retries:
-                try:
-                    success, frag_content = self._download_fragment(ctx, fragment_url, info_dict)
-                    if not success:
-                        return False
-                    self._append_fragment(ctx, frag_content)
-                    break
-                except compat_urllib_error.HTTPError as err:
-                    # YouTube may often return 404 HTTP error for a fragment causing the
-                    # whole download to fail. However if the same fragment is immediately
-                    # retried with the same request data this usually succeeds (1-2 attempts
-                    # is usually enough) thus allowing to download the whole file successfully.
-                    # To be future-proof we will retry all fragments that fail with any
-                    # HTTP error.
-                    count += 1
-                    if count <= fragment_retries:
-                        self.report_retry_fragment(err, frag_index, count, fragment_retries)
-                except DownloadError:
-                    # Don't retry fragment if error occurred during HTTP downloading
-                    # itself since it has own retry settings
-                    if not fatal:
-                        self.report_skip_fragment(frag_index)
-                        break
-                    raise
-
-            if count > fragment_retries:
-                if not fatal:
-                    self.report_skip_fragment(frag_index)
-                    continue
-                self.report_error('giving up after %s fragment retries' % fragment_retries)
-                return False
+            fragments_to_download.append({
+                'frag_index': frag_index,
+                'index': i,
+                'url': fragment_url,
+            })
 
         if real_downloader:
+            self.to_screen(
+                '[%s] Fragment downloads will be delegated to %s' % (self.FD_NAME, real_downloader.get_basename()))
             info_copy = info_dict.copy()
             info_copy['fragments'] = fragments_to_download
             fd = real_downloader(self.ydl, self.params)
-            # TODO: Make progress updates work without hooking twice
-            # for ph in self._progress_hooks:
-            #     fd.add_progress_hook(ph)
-            success = fd.real_download(filename, info_copy)
-            if not success:
-                return False
-        else:
-            self._finish_frag_download(ctx)
-        return True
+            return fd.real_download(filename, info_copy)
+
+        return self.download_and_append_fragments(ctx, fragments_to_download, info_dict)