EXT-X-GAP support

README.rst

@@ -64,6 +64,7 @@ Supported tags
 * #EXT-X-SKIP
 * `#EXT-X-SESSION-DATA`_
 * `#EXT-X-DATERANGE`_
+* `#EXT-X-GAP`_
 
 Encryption keys
 ---------------
@@ -254,6 +255,7 @@ the same thing.
 .. _#EXT-X-INDEPENDENT-SEGMENTS: https://tools.ietf.org/html/rfc8216#section-4.3.5.1
 .. _#EXT-X-START: https://tools.ietf.org/html/rfc8216#section-4.3.5.2
 .. _#EXT-X-DATERANGE: https://tools.ietf.org/html/rfc8216#section-4.3.2.7
+.. _#EXT-X-GAP: https://tools.ietf.org/html/draft-pantos-hls-rfc8216bis-05#section-4.4.2.7
 .. _issue 1: https://github.com/globocom/m3u8/issues/1
 .. _variant streams: https://tools.ietf.org/html/rfc8216#section-6.2.4
 .. _example here: http://tools.ietf.org/html/draft-pantos-http-live-streaming-08#section-8.5

m3u8/model.py

@@ -419,12 +419,15 @@ class Segment(BasePathMixin):
 
     `dateranges`
       any dateranges that should  preceed the segment
+
+    `gap_tag`
+      GAP tag indicates that a Media Segment is missing
     '''
 
     def __init__(self, uri=None, base_uri=None, program_date_time=None, current_program_date_time=None,
                  duration=None, title=None, byterange=None, cue_out=False, cue_out_start=False,
                  cue_in=False, discontinuity=False, key=None, scte35=None, scte35_duration=None,
-                 keyobject=None, parts=None, init_section=None, dateranges=None):
+                 keyobject=None, parts=None, init_section=None, dateranges=None, gap_tag=None):
         self.uri = uri
         self.duration = duration
         self.title = title
@@ -445,6 +448,7 @@ def __init__(self, uri=None, base_uri=None, program_date_time=None, current_prog
         else:
             self.init_section = None
         self.dateranges = DateRangeList( [ DateRange(**daterange) for daterange in dateranges ] if dateranges else [] )
+        self.gap_tag = gap_tag
 
         # Key(base_uri=base_uri, **key) if key else None
 
@@ -507,6 +511,9 @@ def dumps(self, last_segment):
             if self.byterange:
                 output.append('#EXT-X-BYTERANGE:%s\n' % self.byterange)
 
+            if self.gap_tag:
+                output.append('#EXT-X-GAP\n')
+
             output.append(self.uri)
 
         return ''.join(output)
@@ -583,15 +590,21 @@ class PartialSegment(BasePathMixin):
       the Partial Segment contains an independent frame
 
     `gap`
-      the Partial Segment is not available
+      GAP attribute indicates the Partial Segment is not available
 
     `dateranges`
       any dateranges that should preceed the partial segment
+
+    `gap_tag`
+      GAP tag indicates one or more of the parent Media Segment's Partial
+      Segments have a GAP=YES attribute. This tag should appear immediately
+      after the first EXT-X-PART tag in the Parent Segment with a GAP=YES
+      attribute.
     '''
 
     def __init__(self, base_uri, uri, duration, program_date_time=None,
                  current_program_date_time=None, byterange=None,
-                 independent=None, gap=None, dateranges=None):
+                 independent=None, gap=None, dateranges=None, gap_tag=None):
         self.base_uri = base_uri
         self.uri = uri
         self.duration = duration
@@ -601,6 +614,7 @@ def __init__(self, base_uri, uri, duration, program_date_time=None,
         self.independent = independent
         self.gap = gap
         self.dateranges = DateRangeList( [ DateRange(**daterange) for daterange in dateranges ] if dateranges else [] )
+        self.gap_tag = gap_tag
 
     def dumps(self, last_segment):
         output = []
@@ -609,6 +623,9 @@ def dumps(self, last_segment):
             output.append(str(self.dateranges))
             output.append('\n')
 
+        if self.gap_tag:
+            output.append('#EXT-X-GAP\n')
+
         output.append('#EXT-X-PART:DURATION=%s,URI="%s"' % (
             int_or_float_to_string(self.duration), self.uri
         ))

m3u8/parser.py

@@ -187,6 +187,9 @@ def parse(content, strict=False, custom_tags_parser=None):
         elif line.startswith(protocol.ext_x_daterange):
             _parse_daterange(line, data, state)
 
+        elif line.startswith(protocol.ext_x_gap):
+            state['gap'] = True
+
         # Comments and whitespace
         elif line.startswith('#'):
             if callable(custom_tags_parser):
@@ -264,6 +267,7 @@ def _parse_ts_chunk(line, data, state):
     if state.get('current_segment_map'):
         segment['init_section'] = state['current_segment_map']
     segment['dateranges'] = state.pop('dateranges', None)
+    segment['gap_tag'] = state.pop('gap', None)
     data['segments'].append(segment)
 
 
@@ -434,6 +438,7 @@ def _parse_part(line, data, state):
         state['current_program_date_time'] += datetime.timedelta(seconds=part['duration'])
 
     part['dateranges'] = state.pop('dateranges', None)
+    part['gap_tag'] = state.pop('gap', None)
 
     if 'segment' not in state:
         state['segment'] = {}

m3u8/protocol.py

@@ -36,3 +36,4 @@
 ext_x_session_key = '#EXT-X-SESSION-KEY'
 ext_x_preload_hint = '#EXT-X-PRELOAD-HINT'
 ext_x_daterange = "#EXT-X-DATERANGE"
+ext_x_gap = "#EXT-X-GAP"

tests/playlists.py

@@ -988,4 +988,29 @@
 #EXT-X-PART:DURATION=1,URI="filePart271.c.ts"
 '''
 
+GAP_PLAYLIST = '''
+#EXTM3U
+#EXT-X-MEDIA-SEQUENCE:14
+#EXT-X-VERSION:7
+#EXT-X-TARGETDURATION:10
+#EXTINF:9.84317,
+fileSequence14.ts
+#EXTINF:8.75875,
+#EXT-X-GAP
+missing-Sequence15.ts
+#EXTINF:9.88487,
+#EXT-X-GAP
+missing-Sequence16.ts
+#EXTINF:9.09242,
+fileSequence17.ts
+'''
+
+GAP_IN_PARTS_PLAYLIST = '''
+#EXTM3U
+#EXT-X-PART:DURATION=1,URI="filePart271.a.ts"
+#EXT-X-PART:DURATION=1,URI="filePart271.b.ts",GAP=YES
+#EXT-X-GAP
+#EXT-X-PART:DURATION=1,URI="filePart271.c.ts"
+'''
+
 del abspath, dirname, join

tests/test_model.py

@@ -1287,6 +1287,34 @@ def test_daterange_in_parts():
 
     assert expected in result
 
+def test_add_gap():
+    obj = m3u8.Segment(
+        uri='fileSequence271.ts',
+        duration=4,
+        gap_tag=True
+    )
+
+    result = str(obj)
+    expected = '#EXTINF:4,\n#EXT-X-GAP\nfileSequence271.ts'
+
+    assert result == expected
+
+def test_gap():
+    obj = m3u8.M3U8(playlists.GAP_PLAYLIST)
+
+    result = obj.dumps().strip()
+    expected = playlists.GAP_PLAYLIST.strip()
+
+    assert result == expected
+
+def test_gap_in_parts():
+    obj = m3u8.M3U8(playlists.GAP_IN_PARTS_PLAYLIST)
+
+    result = obj.dumps().strip()
+    expected = playlists.GAP_IN_PARTS_PLAYLIST.strip()
+
+    assert result == expected
+
 # custom asserts
 
 

tests/test_parser.py

@@ -454,3 +454,23 @@ def test_date_range_in_parts():
     assert data['segments'][0]['parts'][2]['dateranges'][0]['start_date'] == '2020-03-10T07:48:02Z'
     assert data['segments'][0]['parts'][2]['dateranges'][0]['class'] == 'test_class'
     assert data['segments'][0]['parts'][2]['dateranges'][0]['end_on_next'] == 'YES'
+
+def test_gap():
+    data = m3u8.parse(playlists.GAP_PLAYLIST)
+
+    assert data['segments'][0]['gap_tag'] is None
+    assert data['segments'][1]['gap_tag'] == True
+    assert data['segments'][2]['gap_tag'] == True
+    assert data['segments'][3]['gap_tag'] is None
+
+def test_gap_in_parts():
+    data = m3u8.parse(playlists.GAP_IN_PARTS_PLAYLIST)
+
+    print(data['segments'][0]['parts'])
+
+    assert data['segments'][0]['parts'][0]['gap_tag'] is None
+    assert data['segments'][0]['parts'][0].get('gap', None) is None
+    assert data['segments'][0]['parts'][1]['gap_tag'] is None
+    assert data['segments'][0]['parts'][1]['gap'] == 'YES'
+    assert data['segments'][0]['parts'][2]['gap_tag'] == True
+    assert data['segments'][0]['parts'][2].get('gap', None) is None