Differential D95 Diff 315 swh/objstorage/multiplexer/multiplexer_objstorage.py

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swh/objstorage/multiplexer/multiplexer_objstorage.py

Show First 20 Lines • Show All 47 Lines • ▼ Show 20 Lines	Example 2:
If a content starting with 0, 1 or 2 is present in the storage_v1, it		If a content starting with 0, 1 or 2 is present in the storage_v1, it
would be ignored anyway.		would be ignored anyway.
"""		"""

def __init__(self, storages):		def __init__(self, storages):
self.storages = storages		self.storages = storages

def __contains__(self, obj_id):		def __contains__(self, obj_id):
		""" Indicates if the given object is present in the storage

		See base class [ObjStorage].
		"""
for storage in self.storages:		for storage in self.storages:
if obj_id in storage:		if obj_id in storage:
return True		return True
return False		return False

def __iter__(self):		def __iter__(self):
		""" Iterates over the content of each storages

		Due to the demultiplexer nature, same content can be in multiple
		storages and may be yielded multiple times.

		Warning: The `__iter__` methods frequently have bad performance. You
		almost certainly don't want to use this method in production.
		"""
for storage in self.storages:		for storage in self.storages:
yield from storage		yield from storage

def __len__(self):		def __len__(self):
""" Returns the number of files in the storage.		""" Compute the number of objects in the current object storage.

		Identical objects present in multiple storages will be counted as
		multiple objects.
		Warning: this currently uses `__iter__`, its warning about bad
		performance applies.

Warning: Multiple files may represent the same content, so this method		Returns:
does not indicate how many different contents are in the storage.		number of objects contained in the storage.
"""		"""
return sum(map(len, self.storages))		return sum(map(len, self.storages))

def add(self, content, obj_id=None, check_presence=True):		def add(self, content, obj_id=None, check_presence=True):
""" Add a new object to the object storage.		""" Add a new object to the object storage.

If the adding step works in all the storages that accept this content,		If the adding step works in all the storages that accept this content,
this is a success. Otherwise, the full adding step is an error even if		this is a success. Otherwise, the full adding step is an error even if
Show All 13 Lines	def add(self, content, obj_id=None, check_presence=True):
content.		content.
"""		"""
return [storage.add(content, obj_id, check_presence)		return [storage.add(content, obj_id, check_presence)
for storage in self.storages].pop()		for storage in self.storages].pop()

def restore(self, content, obj_id=None):		def restore(self, content, obj_id=None):
""" Restore a content that have been corrupted.		""" Restore a content that have been corrupted.

This function is identical to add_bytes but does not check if		See base class [ObjStorage] & self.add() method.
the object id is already in the file system.

(see "add" method)

Args:
content: content of the object to be added to the storage
obj_id: checksums of `bytes` as computed by ID_HASH_ALGO. When
given, obj_id will be trusted to match bytes. If missing,
obj_id will be computed on the fly.

Returns:
an id of the object into the storage. As the write-storages are
always readable as well, any id will be valid to retrieve a
content.
"""		"""
return [storage.restore(content, obj_id)		return [storage.restore(content, obj_id)
for storage in self.storages].pop()		for storage in self.storages].pop()

def get(self, obj_id):		def get(self, obj_id):
""" Retrieve the content of a given object.		""" Retrieve the content of a given object.

Args:		See base class [ObjStorage].
obj_id: object id.

Returns:
the content of the requested object as bytes.

Raises:
ObjNotFoundError: if the requested object is missing.
"""		"""
for storage in self.storages:		for storage in self.storages:
try:		try:
return storage.get(obj_id)		return storage.get(obj_id)
except ObjNotFoundError:		except ObjNotFoundError:
continue		continue
# If no storage contains this content, raise the error		# If no storage contains this content, raise the error
raise ObjNotFoundError(obj_id)		raise ObjNotFoundError(obj_id)

def check(self, obj_id):		def check(self, obj_id):
""" Perform an integrity check for a given object.		""" Perform an integrity check for a given object.

Verify that the file object is in place and that the gziped content		See base class [ObjStorage].
matches the object id.

Args:
obj_id: object id.

Raises:
ObjNotFoundError: if the requested object is missing.
Error: if the request object is corrupted.
"""		"""
nb_present = 0		nb_present = 0
for storage in self.storages:		for storage in self.storages:
try:		try:
storage.check(obj_id)		storage.check(obj_id)
except ObjNotFoundError:		except ObjNotFoundError:
continue		continue
else:		else:
nb_present += 1		nb_present += 1
# If there is an Error because of a corrupted file, then let it pass.		# If there is an Error because of a corrupted file, then let it pass.

# Raise the ObjNotFoundError only if the content coulnd't be found in		# Raise the ObjNotFoundError only if the content coulnd't be found in
# all the storages.		# all the storages.
if nb_present == 0:		if nb_present == 0:
raise ObjNotFoundError(obj_id)		raise ObjNotFoundError(obj_id)

def get_random(self, batch_size):		def get_random(self, batch_size):
""" Get random ids of existing contents		""" Get random ids of existing contents

This method is used in order to get random ids to perform		See base class [ObjStorage].
content integrity verifications on random contents.

Attributes:
batch_size (int): Number of ids that will be given

Yields:
An iterable of ids of contents that are in the current object
storage.
"""		"""
storages_set = [storage for storage in self.storages		storages_set = [storage for storage in self.storages
if len(storage) > 0]		if len(storage) > 0]
if len(storages_set) <= 0:		if len(storages_set) <= 0:
return []		return []

while storages_set:		while storages_set:
storage = random.choice(storages_set)		storage = random.choice(storages_set)
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