Changeset View
Changeset View
Standalone View
Standalone View
swh/objstorage/cloud/objstorage_cloud.py
| Show All 9 Lines | |||||
| from swh.core import hashutil | from swh.core import hashutil | ||||
| from libcloud.storage import providers | from libcloud.storage import providers | ||||
| from libcloud.storage.types import Provider, ObjectDoesNotExistError | from libcloud.storage.types import Provider, ObjectDoesNotExistError | ||||
| class CloudObjStorage(ObjStorage, metaclass=abc.ABCMeta): | class CloudObjStorage(ObjStorage, metaclass=abc.ABCMeta): | ||||
| """ Abstract ObjStorage that allows connection to a cloud using Libcloud | """Abstract ObjStorage that connect to a cloud using Libcloud | ||||
| Implementations of this class must redefine the _get_provider method to | Implementations of this class must redefine the _get_provider | ||||
| make it return a driver provider (i.e. object that supports `get_driver` | method to make it return a driver provider (i.e. object that | ||||
| method) which return a LibCloud driver | supports `get_driver` method) which return a LibCloud driver (see | ||||
| (see https://libcloud.readthedocs.io/en/latest/storage/api.html). | https://libcloud.readthedocs.io/en/latest/storage/api.html). | ||||
| """ | |||||
| """ | |||||
| def __init__(self, api_key, api_secret_key, container_name): | def __init__(self, api_key, api_secret_key, container_name): | ||||
| self.driver = self._get_driver(api_key, api_secret_key) | self.driver = self._get_driver(api_key, api_secret_key) | ||||
| self.container_name = container_name | self.container_name = container_name | ||||
| self.container = self.driver.get_container( | self.container = self.driver.get_container( | ||||
| container_name=container_name) | container_name=container_name) | ||||
| def _get_driver(self, api_key, api_secret_key): | def _get_driver(self, api_key, api_secret_key): | ||||
| """ Initialize a driver to communicate with the cloud | """Initialize a driver to communicate with the cloud | ||||
| Args: | Args: | ||||
| api_key: key to connect to the API. | api_key: key to connect to the API. | ||||
| api_secret_key: secret key for authentification. | api_secret_key: secret key for authentification. | ||||
| Returns: | Returns: | ||||
| a Libcloud driver to a cloud storage. | a Libcloud driver to a cloud storage. | ||||
| """ | """ | ||||
| # Get the driver class from its description. | # Get the driver class from its description. | ||||
| cls = providers.get_driver(self._get_provider()) | cls = providers.get_driver(self._get_provider()) | ||||
| # Initialize the driver. | # Initialize the driver. | ||||
| return cls(api_key, api_secret_key) | return cls(api_key, api_secret_key) | ||||
| @abc.abstractmethod | @abc.abstractmethod | ||||
| def _get_provider(self): | def _get_provider(self): | ||||
| """ Get a libcloud driver provider | """Get a libcloud driver provider | ||||
| This method must be overriden by subclasses to specify which of the | This method must be overriden by subclasses to specify which | ||||
| native libcloud driver the current storage should connect to. | of the native libcloud driver the current storage should | ||||
| Alternatively, provider for a custom driver may be returned, in which | connect to. Alternatively, provider for a custom driver may | ||||
| case the provider will have tu support `get_driver` method. | be returned, in which case the provider will have tu support | ||||
| `get_driver` method. | |||||
ardumont: have t`o` support | |||||
| """ | """ | ||||
| raise NotImplementedError('%s must implement `get_provider` method' | raise NotImplementedError('%s must implement `get_provider` method' | ||||
| % type(self)) | % type(self)) | ||||
| def __contains__(self, obj_id): | def __contains__(self, obj_id): | ||||
| try: | try: | ||||
| self._get_object(obj_id) | self._get_object(obj_id) | ||||
| except ObjectDoesNotExistError: | except ObjNotFoundError: | ||||
| return False | return False | ||||
| else: | else: | ||||
| return True | return True | ||||
| def __iter__(self): | def __iter__(self): | ||||
| """ Iterate over the objects present in the storage | """ Iterate over the objects present in the storage | ||||
| Warning: Iteration over the contents of a cloud-based object storage | Warning: Iteration over the contents of a cloud-based object storage | ||||
| may have bad efficiency: due to the very high amount of objects in it | may have bad efficiency: due to the very high amount of objects in it | ||||
| and the fact that it is remote, get all the contents of the current | and the fact that it is remote, get all the contents of the current | ||||
| object storage may result in a lot of network requests. | object storage may result in a lot of network requests. | ||||
| You almost certainly don't want to use this method in production. | You almost certainly don't want to use this method in production. | ||||
| """ | """ | ||||
| yield from map(lambda obj: obj.name, | yield from map(lambda obj: obj.name, | ||||
| self.driver.iterate_container_objects(self.container)) | self.driver.iterate_container_objects(self.container)) | ||||
| def __len__(self): | def __len__(self): | ||||
| """ Compute the number of objects in the current object storage. | """Compute the number of objects in the current object storage. | ||||
| Warning: this currently uses `__iter__`, its warning about bad | Warning: this currently uses `__iter__`, its warning about bad | ||||
| performance applies. | performance applies. | ||||
| Returns: | Returns: | ||||
| number of objects contained in the storage. | number of objects contained in the storage. | ||||
| """ | """ | ||||
| return sum(1 for i in self) | return sum(1 for i in self) | ||||
| def add(self, content, obj_id=None, check_presence=True): | def add(self, content, obj_id=None, check_presence=True): | ||||
| if obj_id is None: | if obj_id is None: | ||||
| # Checksum is missing, compute it on the fly. | # Checksum is missing, compute it on the fly. | ||||
| obj_id = compute_hash(content) | obj_id = compute_hash(content) | ||||
| if check_presence and obj_id in self: | if check_presence and obj_id in self: | ||||
| return obj_id | return obj_id | ||||
| self._put_object(content, obj_id) | self._put_object(content, obj_id) | ||||
| return obj_id | return obj_id | ||||
| def restore(self, content, obj_id=None): | def restore(self, content, obj_id=None): | ||||
| return self.add(content, obj_id, chech_presence=False) | return self.add(content, obj_id, check_presence=False) | ||||
| def get(self, obj_id): | def get(self, obj_id): | ||||
| return bytes(self._get_object(obj_id).as_stream()) | return bytes(self._get_object(obj_id).as_stream()) | ||||
| def check(self, obj_id): | def check(self, obj_id): | ||||
| # Check that the file exists, as _get_object raises ObjNotFoundError | # Check that the file exists, as _get_object raises ObjNotFoundError | ||||
| self._get_object(obj_id) | self._get_object(obj_id) | ||||
| # Check the content integrity | # Check the content integrity | ||||
| obj_content = self.get(obj_id) | obj_content = self.get(obj_id) | ||||
| content_obj_id = compute_hash(obj_content) | content_obj_id = compute_hash(obj_content) | ||||
| if content_obj_id != obj_id: | if content_obj_id != obj_id: | ||||
| raise Error(obj_id) | raise Error(obj_id) | ||||
| def _get_object(self, obj_id): | def _get_object(self, obj_id): | ||||
| """ Get a Libcloud wrapper for an object pointer. | """Get a Libcloud wrapper for an object pointer. | ||||
| This wrapper does not retrieve the content of the object direclty. | This wrapper does not retrieve the content of the object | ||||
| direclty. | |||||
| """ | """ | ||||
| hex_obj_id = hashutil.hash_to_hex(obj_id) | hex_obj_id = hashutil.hash_to_hex(obj_id) | ||||
| try: | try: | ||||
| return self.driver.get_object(self.container_name, hex_obj_id) | return self.driver.get_object(self.container_name, hex_obj_id) | ||||
| except ObjectDoesNotExistError as e: | except ObjectDoesNotExistError as e: | ||||
| raise ObjNotFoundError(e.object_name) | raise ObjNotFoundError(e.object_name) | ||||
| def _put_object(self, content, obj_id): | def _put_object(self, content, obj_id): | ||||
| """ Create an object in the cloud storage. | """Create an object in the cloud storage. | ||||
| Created object will contains the content and be referenced by the | Created object will contains the content and be referenced by | ||||
ardumontUnsubmitted Not Done Inline Actionswill contain ardumont: `will contain` | |||||
| given id. | the given id. | ||||
| """ | """ | ||||
| hex_obj_id = hashutil.hash_to_hex(obj_id) | hex_obj_id = hashutil.hash_to_hex(obj_id) | ||||
| self.driver.upload_object_via_stream(iter(content), self.container, | self.driver.upload_object_via_stream(iter(content), self.container, | ||||
| hex_obj_id) | hex_obj_id) | ||||
| def AwsCloudObjStorage(CloudObjStorage): | def AwsCloudObjStorage(CloudObjStorage): | ||||
| """ Cloud-based object storage that works with Amazon's S3 | """Cloud-based object storage that works with Amazon's S3 | ||||
| """ | """ | ||||
| def _get_provider(self): | def _get_provider(self): | ||||
| return Provider.S3 | return Provider.S3 | ||||
| def OpenStackCloudObjStorage(CloudObjStorage): | def OpenStackCloudObjStorage(CloudObjStorage): | ||||
| """ Cloud-based object storage based on OpenStack Swift | """Cloud-based object storage based on OpenStack Swift | ||||
| """ | """ | ||||
| def _get_provider(self): | def _get_provider(self): | ||||
| return Provider.OPENSTACK_SWIFT | return Provider.OPENSTACK_SWIFT | ||||
have t`o` support