import cStringIO as StringIO import os import logging import copy from cryptography.hazmat.backends import default_backend from cryptography.hazmat.primitives import hashes from cryptography.hazmat.primitives import serialization from cryptography.hazmat.primitives.asymmetric import padding from cachetools import lru_cache from itertools import chain from datetime import datetime, timedelta from botocore.signers import CloudFrontSigner from boto.exception import S3ResponseError import boto.s3.connection import boto.s3.multipart import boto.gs.connection import boto.s3.key import boto.gs.key from io import BufferedIOBase from uuid import uuid4 from collections import namedtuple from util.registry import filelike from storage.basestorage import BaseStorageV2 logger = logging.getLogger(__name__) _PartUploadMetadata = namedtuple('_PartUploadMetadata', ['path', 'offset', 'length']) _CHUNKS_KEY = 'chunks' class StreamReadKeyAsFile(BufferedIOBase): def __init__(self, key): self._key = key def read(self, amt=None): if self.closed: return None resp = self._key.read(amt) return resp def readable(self): return True @property def closed(self): return self._key.closed def close(self): self._key.close(fast=True) class _CloudStorage(BaseStorageV2): def __init__(self, context, connection_class, key_class, connect_kwargs, upload_params, storage_path, bucket_name, access_key=None, secret_key=None): super(_CloudStorage, self).__init__() self.minimum_chunk_size = 5 * 1024 * 1024 self.maximum_chunk_size = None self._initialized = False self._bucket_name = bucket_name self._access_key = access_key self._secret_key = secret_key self._root_path = storage_path self._connection_class = connection_class self._key_class = key_class self._upload_params = upload_params self._connect_kwargs = connect_kwargs self._cloud_conn = None self._cloud_bucket = None self._context = context def _initialize_cloud_conn(self): if not self._initialized: self._cloud_conn = self._connection_class(self._access_key, self._secret_key, **self._connect_kwargs) self._cloud_bucket = self._cloud_conn.get_bucket(self._bucket_name, validate=False) self._initialized = True def _debug_key(self, key): """Used for debugging only.""" orig_meth = key.bucket.connection.make_request def new_meth(*args, **kwargs): print '#' * 16 print args print kwargs print '#' * 16 return orig_meth(*args, **kwargs) key.bucket.connection.make_request = new_meth def _init_path(self, path=None): path = os.path.join(self._root_path, path) if path else self._root_path if path and path[0] == '/': return path[1:] return path def get_cloud_conn(self): self._initialize_cloud_conn() return self._cloud_conn def get_cloud_bucket(self): return self._cloud_bucket def get_content(self, path): self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) if not key.exists(): raise IOError('No such key: \'{0}\''.format(path)) return key.get_contents_as_string() def put_content(self, path, content): self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) key.set_contents_from_string(content, **self._upload_params) return path def get_supports_resumable_downloads(self): return True def get_direct_download_url(self, path, request_ip=None, expires_in=60, requires_cors=False, head=False): self._initialize_cloud_conn() path = self._init_path(path) k = self._key_class(self._cloud_bucket, path) if head: return k.generate_url(expires_in, 'HEAD') return k.generate_url(expires_in) def get_direct_upload_url(self, path, mime_type, requires_cors=True): self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) url = key.generate_url(300, 'PUT', headers={'Content-Type': mime_type}, encrypt_key=True) return url def stream_read(self, path): self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) if not key.exists(): raise IOError('No such key: \'{0}\''.format(path)) while True: buf = key.read(self.buffer_size) if not buf: break yield buf def stream_read_file(self, path): self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) if not key.exists(): raise IOError('No such key: \'{0}\''.format(path)) return StreamReadKeyAsFile(key) def __initiate_multipart_upload(self, path, content_type, content_encoding): # Minimum size of upload part size on S3 is 5MB self._initialize_cloud_conn() path = self._init_path(path) metadata = {} if content_type is not None: metadata['Content-Type'] = content_type if content_encoding is not None: metadata['Content-Encoding'] = content_encoding if self._context.metric_queue is not None: self._context.metric_queue.multipart_upload_start.Inc() return self._cloud_bucket.initiate_multipart_upload(path, metadata=metadata, **self._upload_params) def stream_write(self, path, fp, content_type=None, content_encoding=None): """ Writes the data found in the file-like stream tot he given path. Raises an IOError if the write fails. """ _, write_error = self._stream_write_internal(path, fp, content_type, content_encoding) if write_error is not None: logger.error('Error when trying to stream_write path `%s`: %s', path, write_error) raise IOError('Exception when trying to stream_write path') def _stream_write_internal(self, path, fp, content_type=None, content_encoding=None, cancel_on_error=True, size=filelike.READ_UNTIL_END): """ Writes the data found in the file-like stream to the given path, with optional limit on size. Note that this method returns a *tuple* of (bytes_written, write_error) and should *not* raise an exception (such as IOError) if a problem uploading occurred. ALWAYS check the returned tuple on calls to this method. """ write_error = None try: mp = self.__initiate_multipart_upload(path, content_type, content_encoding) except S3ResponseError as e: logger.exception('Exception when initiating multipart upload') return 0, e # We are going to reuse this but be VERY careful to only read the number of bytes written to it buf = StringIO.StringIO() num_part = 1 total_bytes_written = 0 while size == filelike.READ_UNTIL_END or total_bytes_written < size: bytes_to_copy = self.minimum_chunk_size if size != filelike.READ_UNTIL_END: # We never want to ask for more bytes than our caller has indicated to copy bytes_to_copy = min(bytes_to_copy, size - total_bytes_written) buf.seek(0) try: # Stage the bytes into the buffer for use with the multipart upload file API bytes_staged = self.stream_write_to_fp(fp, buf, bytes_to_copy) if bytes_staged == 0: break buf.seek(0) mp.upload_part_from_file(buf, num_part, size=bytes_staged) total_bytes_written += bytes_staged num_part += 1 except (S3ResponseError, IOError) as e: logger.warn('Error when writing to stream in stream_write_internal at path %s: %s', path, e) write_error = e if self._context.metric_queue is not None: self._context.metric_queue.multipart_upload_end.Inc(labelvalues=['failure']) if cancel_on_error: try: mp.cancel_upload() except (S3ResponseError, IOError): logger.exception('Could not cancel upload') return 0, write_error else: break if total_bytes_written > 0: if self._context.metric_queue is not None: self._context.metric_queue.multipart_upload_end.Inc(labelvalues=['success']) self._perform_action_with_retry(mp.complete_upload) return total_bytes_written, write_error def exists(self, path): self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) return key.exists() def remove(self, path): self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) if key.exists(): # It's a file key.delete() return # We assume it's a directory if not path.endswith('/'): path += '/' for key in self._cloud_bucket.list(prefix=path): key.delete() def get_checksum(self, path): self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) k = self._cloud_bucket.lookup(key) if k is None: raise IOError('No such key: \'{0}\''.format(path)) return k.etag[1:-1][:7] def copy_to(self, destination, path): """ Copies the given path from this storage to the destination storage. """ self._initialize_cloud_conn() # First try to copy directly via boto, but only if the storages are the # same type, with the same access information. if (self.__class__ == destination.__class__ and self._access_key and self._secret_key and self._access_key == destination._access_key and self._secret_key == destination._secret_key and self._connect_kwargs == destination._connect_kwargs): # Initialize the cloud connection on the destination as well. destination._initialize_cloud_conn() # Check the buckets for both the source and destination locations. if self._cloud_bucket is None: logger.error('Cloud bucket not found for location %s; Configuration is probably invalid!', self._bucket_name) return if destination._cloud_bucket is None: logger.error('Cloud bucket not found for location %s; Configuration is probably invalid!', destination._bucket_name) return # Perform the copy. logger.debug('Copying file from %s to %s via a direct boto copy', self._cloud_bucket, destination._cloud_bucket) source_path = self._init_path(path) source_key = self._key_class(self._cloud_bucket, source_path) dest_path = destination._init_path(path) source_key.copy(destination._cloud_bucket, dest_path) return # Fallback to a slower, default copy. logger.debug('Copying file from %s to %s via a streamed copy', self._cloud_bucket, destination) with self.stream_read_file(path) as fp: destination.stream_write(path, fp) def _rel_upload_path(self, uuid): return 'uploads/{0}'.format(uuid) def initiate_chunked_upload(self): self._initialize_cloud_conn() random_uuid = str(uuid4()) metadata = { _CHUNKS_KEY: [], } return random_uuid, metadata def stream_upload_chunk(self, uuid, offset, length, in_fp, storage_metadata, content_type=None): self._initialize_cloud_conn() # We are going to upload each chunk to a separate key chunk_path = self._rel_upload_path(str(uuid4())) bytes_written, write_error = self._stream_write_internal(chunk_path, in_fp, cancel_on_error=False, size=length, content_type=content_type) new_metadata = copy.deepcopy(storage_metadata) # We are only going to track keys to which data was confirmed written if bytes_written > 0: new_metadata[_CHUNKS_KEY].append(_PartUploadMetadata(chunk_path, offset, bytes_written)) return bytes_written, new_metadata, write_error def _chunk_generator(self, chunk_list): for chunk in chunk_list: yield filelike.StreamSlice(self.stream_read_file(chunk.path), 0, chunk.length) @staticmethod def _chunk_list_from_metadata(storage_metadata): return [_PartUploadMetadata(*chunk_args) for chunk_args in storage_metadata[_CHUNKS_KEY]] def _client_side_chunk_join(self, final_path, chunk_list): # If there's only one chunk, just "move" (copy and delete) the key and call it a day. if len(chunk_list) == 1: chunk_path = self._init_path(chunk_list[0].path) abs_final_path = self._init_path(final_path) # Let the copy raise an exception if it fails. self._cloud_bucket.copy_key(abs_final_path, self._bucket_name, chunk_path) # Attempt to clean up the old chunk. try: self._cloud_bucket.delete_key(chunk_path) except IOError: # We failed to delete a chunk. This sucks, but we shouldn't fail the push. msg = 'Failed to clean up chunk %s for move of %s' logger.exception(msg, chunk_path, abs_final_path) else: # Concatenate and write all the chunks as one key. concatenated = filelike.FilelikeStreamConcat(self._chunk_generator(chunk_list)) self.stream_write(final_path, concatenated) # Attempt to clean up all the chunks. for chunk in chunk_list: try: self._cloud_bucket.delete_key(self._init_path(chunk.path)) except IOError: # We failed to delete a chunk. This sucks, but we shouldn't fail the push. msg = 'Failed to clean up chunk %s for reupload of %s' logger.exception(msg, chunk.path, final_path) @staticmethod def _perform_action_with_retry(action, *args, **kwargs): # Note: Sometimes Amazon S3 simply raises an internal error when trying to complete a # an action. The recommendation is to simply try calling the action again. for remaining_retries in range(2, -1, -1): try: action(*args, **kwargs) break except S3ResponseError as s3re: if remaining_retries and s3re.status == 200 and s3re.error_code == 'InternalError': # Weird internal error case. Retry. continue # Otherwise, raise it. logger.exception('Exception trying to perform action %s', action) raise s3re @staticmethod def _rechunk(chunk, max_chunk_size): """ Rechunks the chunk list to meet maximum chunk size restrictions for the storage engine. """ if max_chunk_size is None or chunk.length <= max_chunk_size: yield chunk else: newchunk_length = chunk.length / 2 first_subchunk = _PartUploadMetadata(chunk.path, chunk.offset, newchunk_length) second_subchunk = _PartUploadMetadata(chunk.path, chunk.offset + newchunk_length, chunk.length - newchunk_length) for subchunk in chain(_CloudStorage._rechunk(first_subchunk, max_chunk_size), _CloudStorage._rechunk(second_subchunk, max_chunk_size)): yield subchunk def complete_chunked_upload(self, uuid, final_path, storage_metadata, force_client_side=False): self._initialize_cloud_conn() chunk_list = self._chunk_list_from_metadata(storage_metadata) # Here is where things get interesting: we are going to try to assemble this server side # In order to be a candidate all parts (after offsets have been computed) must be at least 5MB server_side_assembly = False if not force_client_side: server_side_assembly = True for chunk_offset, chunk in enumerate(chunk_list): # If the chunk is both too small, and not the last chunk, we rule out server side assembly if chunk.length < self.minimum_chunk_size and (chunk_offset + 1) < len(chunk_list): server_side_assembly = False break if server_side_assembly: logger.debug('Performing server side assembly of multi-part upload for: %s', final_path) try: # Awesome, we can do this completely server side, now we have to start a new multipart # upload and use copy_part_from_key to set all of the chunks. mpu = self.__initiate_multipart_upload(final_path, content_type=None, content_encoding=None) updated_chunks = chain.from_iterable([_CloudStorage._rechunk(c, self.maximum_chunk_size) for c in chunk_list]) for index, chunk in enumerate(updated_chunks): abs_chunk_path = self._init_path(chunk.path) self._perform_action_with_retry(mpu.copy_part_from_key, self.get_cloud_bucket().name, abs_chunk_path, index + 1, start=chunk.offset, end=chunk.length + chunk.offset - 1) self._perform_action_with_retry(mpu.complete_upload) except IOError as ioe: # Something bad happened, log it and then give up msg = 'Exception when attempting server-side assembly for: %s' logger.exception(msg, final_path) mpu.cancel_upload() raise ioe else: # We are going to turn all of the server side objects into a single file-like stream, and # pass that to stream_write to chunk and upload the final object. self._client_side_chunk_join(final_path, chunk_list) def cancel_chunked_upload(self, uuid, storage_metadata): self._initialize_cloud_conn() # We have to go through and delete all of the uploaded chunks for chunk in self._chunk_list_from_metadata(storage_metadata): self.remove(chunk.path) class S3Storage(_CloudStorage): def __init__(self, context, storage_path, s3_bucket, s3_access_key=None, s3_secret_key=None, host=None, port=None): upload_params = { 'encrypt_key': True, } connect_kwargs = {} if host: if host.startswith('http:') or host.startswith('https:'): raise ValueError('host name must not start with http:// or https://') connect_kwargs['host'] = host if port: connect_kwargs['port'] = int(port) super(S3Storage, self).__init__(context, boto.s3.connection.S3Connection, boto.s3.key.Key, connect_kwargs, upload_params, storage_path, s3_bucket, access_key=s3_access_key or None, secret_key=s3_secret_key or None) self.maximum_chunk_size = 5 * 1024 * 1024 * 1024 # 5GB. def setup(self): self.get_cloud_bucket().set_cors_xml(""" * GET 3000 Authorization * PUT 3000 Content-Type x-amz-acl origin """) class GoogleCloudStorage(_CloudStorage): def __init__(self, context, storage_path, access_key, secret_key, bucket_name): upload_params = {} connect_kwargs = {} super(GoogleCloudStorage, self).__init__(context, boto.gs.connection.GSConnection, boto.gs.key.Key, connect_kwargs, upload_params, storage_path, bucket_name, access_key, secret_key) def setup(self): self.get_cloud_bucket().set_cors_xml(""" * GET PUT Content-Type 3000 """) def _stream_write_internal(self, path, fp, content_type=None, content_encoding=None, cancel_on_error=True, size=filelike.READ_UNTIL_END): """ Writes the data found in the file-like stream to the given path, with optional limit on size. Note that this method returns a *tuple* of (bytes_written, write_error) and should *not* raise an exception (such as IOError) if a problem uploading occurred. ALWAYS check the returned tuple on calls to this method. """ # Minimum size of upload part size on S3 is 5MB self._initialize_cloud_conn() path = self._init_path(path) key = self._key_class(self._cloud_bucket, path) if content_type is not None: key.set_metadata('Content-Type', content_type) if content_encoding is not None: key.set_metadata('Content-Encoding', content_encoding) if size != filelike.READ_UNTIL_END: fp = filelike.StreamSlice(fp, 0, size) # TODO figure out how to handle cancel_on_error=False try: key.set_contents_from_stream(fp) except IOError as ex: return 0, ex return key.size, None def complete_chunked_upload(self, uuid, final_path, storage_metadata): self._initialize_cloud_conn() # Boto does not support GCS's multipart upload API because it differs from S3, so # we are forced to join it all locally and then reupload. # See https://github.com/boto/boto/issues/3355 chunk_list = self._chunk_list_from_metadata(storage_metadata) self._client_side_chunk_join(final_path, chunk_list) class RadosGWStorage(_CloudStorage): def __init__(self, context, hostname, is_secure, storage_path, access_key, secret_key, bucket_name, port=None): upload_params = {} connect_kwargs = { 'host': hostname, 'is_secure': is_secure, 'calling_format': boto.s3.connection.OrdinaryCallingFormat(), } if port: connect_kwargs['port'] = int(port) super(RadosGWStorage, self).__init__(context, boto.s3.connection.S3Connection, boto.s3.key.Key, connect_kwargs, upload_params, storage_path, bucket_name, access_key, secret_key) # TODO remove when radosgw supports cors: http://tracker.ceph.com/issues/8718#change-38624 def get_direct_download_url(self, path, request_ip=None, expires_in=60, requires_cors=False, head=False): if requires_cors: return None return super(RadosGWStorage, self).get_direct_download_url(path, request_ip, expires_in, requires_cors, head) # TODO remove when radosgw supports cors: http://tracker.ceph.com/issues/8718#change-38624 def get_direct_upload_url(self, path, mime_type, requires_cors=True): if requires_cors: return None return super(RadosGWStorage, self).get_direct_upload_url(path, mime_type, requires_cors) def complete_chunked_upload(self, uuid, final_path, storage_metadata): self._initialize_cloud_conn() # RadosGW does not support multipart copying from keys, so we are forced to join # it all locally and then reupload. # See https://github.com/ceph/ceph/pull/5139 chunk_list = self._chunk_list_from_metadata(storage_metadata) self._client_side_chunk_join(final_path, chunk_list) class CloudFrontedS3Storage(S3Storage): """ An S3Storage engine that redirects to CloudFront for all requests outside of AWS. """ def __init__(self, context, cloudfront_distribution_domain, cloudfront_key_id, cloudfront_privatekey_filename, storage_path, s3_bucket, *args, **kwargs): super(CloudFrontedS3Storage, self).__init__(context, storage_path, s3_bucket, *args, **kwargs) self.cloudfront_distribution_domain = cloudfront_distribution_domain self.cloudfront_key_id = cloudfront_key_id self.cloudfront_privatekey = self._load_private_key(cloudfront_privatekey_filename) def get_direct_download_url(self, path, request_ip=None, expires_in=60, requires_cors=False, head=False): # If CloudFront could not be loaded, fall back to normal S3. if self.cloudfront_privatekey is None: return super(CloudFrontedS3Storage, self).get_direct_download_url(path, request_ip, expires_in, requires_cors, head) resolved_ip_info = None logger.debug('Got direct download request for path "%s" with IP "%s"', path, request_ip) if request_ip is not None: # Lookup the IP address in our resolution table and determine whether it is under AWS. # If it is, then return an S3 signed URL, since we are in-network. resolved_ip_info = self._context.ip_resolver.resolve_ip(request_ip) logger.debug('Resolved IP information for IP %s: %s', request_ip, resolved_ip_info) if resolved_ip_info and resolved_ip_info.provider == 'aws': return super(CloudFrontedS3Storage, self).get_direct_download_url(path, request_ip, expires_in, requires_cors, head) url = 'https://%s/%s' % (self.cloudfront_distribution_domain, path) expire_date = datetime.now() + timedelta(seconds=expires_in) signer = self._get_cloudfront_signer() signed_url = signer.generate_presigned_url(url, date_less_than=expire_date) logger.debug('Returning CloudFront URL for path "%s" with IP "%s": %s', path, resolved_ip_info, signed_url) return signed_url @lru_cache(maxsize=1) def _get_cloudfront_signer(self): return CloudFrontSigner(self.cloudfront_key_id, self._get_rsa_signer()) @lru_cache(maxsize=1) def _get_rsa_signer(self): private_key = self.cloudfront_privatekey def handler(message): signer = private_key.signer(padding.PKCS1v15(), hashes.SHA1()) signer.update(message) return signer.finalize() return handler @lru_cache(maxsize=1) def _load_private_key(self, cloudfront_privatekey_filename): """ Returns the private key, loaded from the config provider, used to sign direct download URLs to CloudFront. """ if self._context.config_provider is None: return None with self._context.config_provider.get_volume_file(cloudfront_privatekey_filename) as key_file: return serialization.load_pem_private_key( key_file.read(), password=None, backend=default_backend() )