[generic] Add support for BOMs (Fixes #4753)

This commit is contained in:
Philipp Hagemeister 2015-01-23 01:21:30 +01:00
parent 317239b097
commit 61ca9a80b3
3 changed files with 39 additions and 1 deletions

View File

@ -28,6 +28,7 @@
fix_xml_ampersands,
InAdvancePagedList,
intlist_to_bytes,
is_html,
js_to_json,
limit_length,
OnDemandPagedList,
@ -417,5 +418,21 @@ def test_age_restricted(self):
self.assertTrue(age_restricted(18, 14))
self.assertFalse(age_restricted(18, 18))
def test_is_html(self):
self.assertFalse(is_html(b'\x49\x44\x43<html'))
self.assertTrue(is_html(b'<!DOCTYPE foo>\xaaa'))
self.assertTrue(is_html( # UTF-8 with BOM
b'\xef\xbb\xbf<!DOCTYPE foo>\xaaa'))
self.assertTrue(is_html( # UTF-16-LE
b'\xff\xfe<\x00h\x00t\x00m\x00l\x00>\x00\xe4\x00'
))
self.assertTrue(is_html( # UTF-16-BE
b'\xfe\xff\x00<\x00h\x00t\x00m\x00l\x00>\x00\xe4'
))
self.assertTrue(is_html( # UTF-32-BE
b'\x00\x00\xFE\xFF\x00\x00\x00<\x00\x00\x00h\x00\x00\x00t\x00\x00\x00m\x00\x00\x00l\x00\x00\x00>\x00\x00\x00\xe4'))
self.assertTrue(is_html( # UTF-32-LE
b'\xFF\xFE\x00\x00<\x00\x00\x00h\x00\x00\x00t\x00\x00\x00m\x00\x00\x00l\x00\x00\x00>\x00\x00\x00\xe4\x00\x00\x00'))
if __name__ == '__main__':
unittest.main()

View File

@ -17,6 +17,7 @@
ExtractorError,
float_or_none,
HEADRequest,
is_html,
orderedSet,
parse_xml,
smuggle_url,
@ -647,7 +648,7 @@ def _real_extract(self, url):
# Maybe it's a direct link to a video?
# Be careful not to download the whole thing!
first_bytes = full_response.read(512)
if not re.match(r'^\s*<', first_bytes.decode('utf-8', 'replace')):
if not is_html(first_bytes):
self._downloader.report_warning(
'URL could be a direct video link, returning it as such.')
upload_date = unified_strdate(

View File

@ -1631,3 +1631,23 @@ def age_restricted(content_limit, age_limit):
if content_limit is None:
return False # Content available for everyone
return age_limit < content_limit
def is_html(first_bytes):
""" Detect whether a file contains HTML by examining its first bytes. """
BOMS = [
(b'\xef\xbb\xbf', 'utf-8'),
(b'\x00\x00\xfe\xff', 'utf-32-be'),
(b'\xff\xfe\x00\x00', 'utf-32-le'),
(b'\xff\xfe', 'utf-16-le'),
(b'\xfe\xff', 'utf-16-be'),
]
for bom, enc in BOMS:
if first_bytes.startswith(bom):
s = first_bytes[len(bom):].decode(enc, 'replace')
break
else:
s = first_bytes.decode('utf-8', 'replace')
return re.match(r'^\s*<', s)