def read(self, size=-1):
"""Read at most `size` bytes from the file (less if there
isn't enough data).
The bytes are returned as an instance of :class:`str`. If
`size` is negative or omitted all data is read.
:Parameters:
- `size` (optional): the number of bytes to read
"""
if size:
remainder = int(self.length) - self.__position
if size < 0 or size > remainder:
size = remainder
data = self.__buffer
chunk_number = (len(data) + self.__position) / self.chunk_size
while len(data) < size:
chunk = yield self.__chunks.find_one({"files_id": self._id,
"n": chunk_number})
if not chunk:
raise CorruptGridFile("no chunk #%d" % chunk_number)
if not data:
data += chunk["data"][self.__position % self.chunk_size:]
else:
data += chunk["data"]
chunk_number += 1
self.__position += size
to_return = data[:size]
self.__buffer = data[size:]
defer.returnValue(to_return)
def next(self):
if self.__current_chunk >= self.__max_chunk:
raise StopIteration
chunk = yield self.__chunks.find_one({"files_id": self.__id,
"n": self.__current_chunk})
if not chunk:
raise CorruptGridFile("no chunk #%d" % self.__current_chunk)
self.__current_chunk += 1
defer.returnValue(str(chunk["data"]))
def __next__(self):
if self.__current_chunk >= self.__max_chunk:
raise StopIteration
chunk = yield self.__chunks.find_one({"files_id": self.__id,
"n": self.__current_chunk})
if not chunk:
raise CorruptGridFile("TxMongo: no chunk #{0}".format(self.__current_chunk))
self.__current_chunk += 1
defer.returnValue(bytes(chunk["data"]))
def process(chunk):
if not chunk:
raise CorruptGridFile("TxMongo: no chunk #{0}".format(state.chunk_number))
if not state.data:
state.data += chunk["data"][self.__position % self.chunk_size:]
else:
state.data += chunk["data"]
state.chunk_number += 1
def ok(chunk):
if not chunk:
raise CorruptGridFile("TxMongo: no chunk #{0}".format(self.__current_chunk))
self.__current_chunk += 1
return bytes(chunk["data"])