class gzip_open_func(object):
"""gzip open func
modes:
(r) read using gzip.GzipFile
(w) write using system gzip
(P) PIPE from `gzip -d` for
"""
def __init__(self, filename, mode='r', path_to_gzip='gzip'):
self._filename = filename
self._mode = mode
self._path_to_gzip = path_to_gzip
self._pickle_safe_init()
def _pickle_safe_init(self):
filename = self._filename
if self._mode[0] == 'w':
args = [self._path_to_gzip, '-f', '-c', '-']
stdout = open(filename, 'wb')
self._stdout = stdout
self.proc = Popen(args, stdin=PIPE, bufsize=0,
stderr=stderr,
stdout=stdout)
self.write = self.proc.stdin.write
self.close = self._close_w
self.filename = filename
elif self._mode[0] == 'r':
self._file = GzipFile(filename, 'rb')
self.read = self._file.read
self.readline = self._file.readline
self.close = self._file.close
else:
raise NotImplementedError
def __getnewargs__(self):
return (self._mode, self._filename)
def __getstate__(self):
result = {}
result['_mode'] = self._mode
result['_filename'] = self._filename
result['_path_to_gzip'] = self._path_to_gzip
return result
def __iter__(self):
if not self._mode == 'r':
raise IOError('cannot iterate over file in write mode')
return self._file.__iter__()
def _close_w(self):
"""returns returncode
"""
self.proc.stdin.flush()
self._stdout.flush()
# self.proc.stdout.flush()
self._stdout.close()
# self.proc.communicate('\x1a')
return
