def delete_tag(filename):
with fileutil.opened(filename, "rb+") as file:
try:
(cls, offset, length) = detect_tag(file)
fileutil.replace_chunk(file, offset, length, bytes())
except NoTagError:
pass
def read(cls, filename, offset=None, encoding="iso-8859-1"):
"""Read an ID3v1 tag from a file."""
with fileutil.opened(filename, "rb") as file:
if offset is None:
file.seek(-128, 2)
else:
file.seek(offset)
data = file.read(128)
return cls.decode(data, encoding=encoding)
def write(self, filename, encoding="iso-8859-1", errors="strict"):
with fileutil.opened(filename, "rb+") as file:
file.seek(-128, 2)
data = file.read(128)
if data[:3] == b"TAG":
file.seek(-128, 2)
else:
file.seek(0, 2)
file.write(self.encode(encoding, errors))
def write(self, filename, encoding="iso-8859-1", errors="strict"):
with fileutil.opened(filename, "rb+") as file:
file.seek(-128, 2)
data = file.read(128)
if data[:3] == b"TAG":
file.seek(-128, 2)
else:
file.seek(0, 2)
file.write(self.encode(encoding, errors))
def read(cls, filename, offset=None, encoding="iso-8859-1"):
"""Read an ID3v1 tag from a file."""
with fileutil.opened(filename, "rb") as file:
if offset is None:
file.seek(-128, 2)
else:
file.seek(offset)
data = file.read(128)
return cls.decode(data, encoding=encoding)
def delete(cls, filename, offset=None):
"""Delete ID3v1 tag from a file (if present)."""
with fileutil.opened(filename, "rb+") as file:
if offset is None:
file.seek(-128, 2)
else:
file.seek(offset)
offset = file.tell()
data = file.read(128)
if data[:3] == b"TAG":
fileutil.replace_chunk(file, offset, 128, b"", in_place=True)
def delete(cls, filename, offset=None):
"""Delete ID3v1 tag from a file (if present)."""
with fileutil.opened(filename, "rb+") as file:
if offset is None:
file.seek(-128, 2)
else:
file.seek(offset)
offset = file.tell()
data = file.read(128)
if data[:3] == b"TAG":
fileutil.replace_chunk(file, offset, 128, b"", in_place=True)
def write(self, filename=None):
if not filename:
filename = self._filename
if not filename:
raise TypeError("invalid file: {0}".format(filename))
with fileutil.opened(filename, "rb+") as file:
try:
(offset, length) = detect_tag(file)[1:3]
except NoTagError:
(offset, length) = (0, 0)
if offset > 0:
delete_tag(file)
(offset, length) = (0, 0)
tag_data = self.encode(size_hint=length)
fileutil.replace_chunk(file, offset, length, tag_data)
def detect_tag(filename):
"""Return type and position of ID3v2 tag in filename.
Returns (tag_class, offset, length), where tag_class
is either Tag22, Tag23, or Tag24, and (offset, length)
is the position of the tag in the file.
"""
with fileutil.opened(filename, "rb") as file:
file.seek(0)
header = file.read(10)
file.seek(0)
if len(header) < 10:
raise NoTagError("File too short")
if header[0:3] != b"ID3":
raise NoTagError("ID3v2 tag not found")
if header[3] not in _tag_versions or header[4] != 0:
raise TagError("Unknown ID3 version: 2.{0}.{1}"
.format(*header[3:5]))
cls = _tag_versions[header[3]]
offset = 0
length = Syncsafe.decode(header[6:10]) + 10
if header[3] == 4 and header[5] & _TAG24_FOOTER:
length += 10
return (cls, offset, length)
def read(cls, filename, offset=0):
"""Read an ID3v2 tag from a file."""
i = 0
with fileutil.opened(filename, "rb") as file:
file.seek(offset)
tag = cls()
tag._read_header(file)
frames = tag._read_frames(file)
for (frameid, bflags, data) in frames:
if len(data) == 0:
warn("{0}: Ignoring empty frame".format(frameid),
EmptyFrameWarning)
else:
frame = tag._decode_frame(frameid, bflags, data, i)
if frame is not None:
l = tag._frames.setdefault(frame.frameid, [])
l.append(frame)
i += 1
try:
tag._filename = file.name
except AttributeError:
pass
return tag
def read_tag(filename):
with fileutil.opened(filename, "rb") as file:
(cls, offset, length) = detect_tag(file)
return cls.read(file, offset)
