import os import posixpath import mimetypes from gzip import GzipFile import datetime from tempfile import SpooledTemporaryFile try: from cStringIO import StringIO except ImportError: from StringIO import StringIO # noqa from django.core.files.base import File from django.core.files.storage import Storage from django.core.exceptions import ImproperlyConfigured, SuspiciousOperation from django.utils.encoding import force_unicode, smart_str, filepath_to_uri try: from boto import __version__ as boto_version from boto.s3.connection import S3Connection, SubdomainCallingFormat from boto.exception import S3ResponseError from boto.s3.key import Key as S3Key from boto.utils import parse_ts except ImportError: raise ImproperlyConfigured("Could not load Boto's S3 bindings.\n" "See https://github.com/boto/boto") from storages.utils import setting boto_version_info = tuple([int(i) for i in boto_version.split('-')[0].split('.')]) if boto_version_info[:2] < (2, 4): raise ImproperlyConfigured("The installed Boto library must be 2.4 or " "higher.\nSee https://github.com/boto/boto") def parse_ts_extended(ts): RFC1123 = '%a, %d %b %Y %H:%M:%S %Z' rv = None try: rv = parse_ts(ts) except ValueError: rv = datetime.datetime.strptime(ts, RFC1123) return rv def safe_join(base, *paths): """ A version of django.utils._os.safe_join for S3 paths. Joins one or more path components to the base path component intelligently. Returns a normalized version of the final path. The final path must be located inside of the base path component (otherwise a ValueError is raised). Paths outside the base path indicate a possible security sensitive operation. """ from urlparse import urljoin base_path = force_unicode(base) base_path = base_path.rstrip('/') paths = [force_unicode(p) for p in paths] final_path = base_path for path in paths: final_path = urljoin(final_path.rstrip('/') + "/", path) # Ensure final_path starts with base_path and that the next character after # the final path is '/' (or nothing, in which case final_path must be # equal to base_path). base_path_len = len(base_path) if (not final_path.startswith(base_path) or final_path[base_path_len:base_path_len + 1] not in ('', '/')): raise ValueError('the joined path is located outside of the base path' ' component') return final_path.lstrip('/') class S3BotoStorageFile(File): """ The default file object used by the S3BotoStorage backend. This file implements file streaming using boto's multipart uploading functionality. The file can be opened in read or write mode. This class extends Django's File class. However, the contained data is only the data contained in the current buffer. So you should not access the contained file object directly. You should access the data via this class. Warning: This file *must* be closed using the close() method in order to properly write the file to S3. Be sure to close the file in your application. """ # TODO: Read/Write (rw) mode may be a bit undefined at the moment. Needs testing. # TODO: When Django drops support for Python 2.5, rewrite to use the # BufferedIO streams in the Python 2.6 io module. buffer_size = setting('AWS_S3_FILE_BUFFER_SIZE', 5242880) def __init__(self, name, mode, storage, buffer_size=None): self._storage = storage self.name = name[len(self._storage.location):].lstrip('/') self._mode = mode self.key = storage.bucket.get_key(self._storage._encode_name(name)) if not self.key and 'w' in mode: self.key = storage.bucket.new_key(storage._encode_name(name)) self._is_dirty = False self._file = None self._multipart = None # 5 MB is the minimum part size (if there is more than one part). # Amazon allows up to 10,000 parts. The default supports uploads # up to roughly 50 GB. Increase the part size to accommodate # for files larger than this. if buffer_size is not None: self.buffer_size = buffer_size self._write_counter = 0 @property def size(self): return self.key.size def _get_file(self): if self._file is None: self._file = SpooledTemporaryFile( max_size=self._storage.max_memory_size, suffix=".S3BotoStorageFile", dir=setting("FILE_UPLOAD_TEMP_DIR", None) ) if 'r' in self._mode: self._is_dirty = False self.key.get_contents_to_file(self._file) self._file.seek(0) if self._storage.gzip and self.key.content_encoding == 'gzip': self._file = GzipFile(mode=self._mode, fileobj=self._file) return self._file def _set_file(self, value): self._file = value file = property(_get_file, _set_file) def read(self, *args, **kwargs): if 'r' not in self._mode: raise AttributeError("File was not opened in read mode.") return super(S3BotoStorageFile, self).read(*args, **kwargs) def write(self, *args, **kwargs): if 'w' not in self._mode: raise AttributeError("File was not opened in write mode.") self._is_dirty = True if self._multipart is None: provider = self.key.bucket.connection.provider upload_headers = { provider.acl_header: self._storage.default_acl } upload_headers.update({'Content-Type': mimetypes.guess_type(self.key.name)[0] or self._storage.key_class.DefaultContentType}) upload_headers.update(self._storage.headers) self._multipart = self._storage.bucket.initiate_multipart_upload( self.key.name, headers=upload_headers, reduced_redundancy=self._storage.reduced_redundancy ) if self.buffer_size <= self._buffer_file_size: self._flush_write_buffer() return super(S3BotoStorageFile, self).write(*args, **kwargs) @property def _buffer_file_size(self): pos = self.file.tell() self.file.seek(0, os.SEEK_END) length = self.file.tell() self.file.seek(pos) return length def _flush_write_buffer(self): """ Flushes the write buffer. """ if self._buffer_file_size: self._write_counter += 1 self.file.seek(0) headers = self._storage.headers.copy() self._multipart.upload_part_from_file( self.file, self._write_counter, headers=headers) self.file.close() self._file = None def close(self): if self._is_dirty: self._flush_write_buffer() self._multipart.complete_upload() else: if not self._multipart is None: self._multipart.cancel_upload() self.key.close() class S3BotoStorage(Storage): """ Amazon Simple Storage Service using Boto This storage backend supports opening files in read or write mode and supports streaming(buffering) data in chunks to S3 when writing. """ connection_class = S3Connection connection_response_error = S3ResponseError file_class = S3BotoStorageFile key_class = S3Key # used for looking up the access and secret key from env vars access_key_names = ['AWS_S3_ACCESS_KEY_ID', 'AWS_ACCESS_KEY_ID'] secret_key_names = ['AWS_S3_SECRET_ACCESS_KEY', 'AWS_SECRET_ACCESS_KEY'] access_key = setting('AWS_S3_ACCESS_KEY_ID', setting('AWS_ACCESS_KEY_ID')) secret_key = setting('AWS_S3_SECRET_ACCESS_KEY', setting('AWS_SECRET_ACCESS_KEY')) file_overwrite = setting('AWS_S3_FILE_OVERWRITE', True) headers = setting('AWS_HEADERS', {}) bucket_name = setting('AWS_STORAGE_BUCKET_NAME') auto_create_bucket = setting('AWS_AUTO_CREATE_BUCKET', False) default_acl = setting('AWS_DEFAULT_ACL', 'public-read') bucket_acl = setting('AWS_BUCKET_ACL', default_acl) querystring_auth = setting('AWS_QUERYSTRING_AUTH', True) querystring_expire = setting('AWS_QUERYSTRING_EXPIRE', 3600) reduced_redundancy = setting('AWS_REDUCED_REDUNDANCY', False) location = setting('AWS_LOCATION', '') encryption = setting('AWS_S3_ENCRYPTION', False) custom_domain = setting('AWS_S3_CUSTOM_DOMAIN') calling_format = setting('AWS_S3_CALLING_FORMAT', SubdomainCallingFormat()) secure_urls = setting('AWS_S3_SECURE_URLS', True) file_name_charset = setting('AWS_S3_FILE_NAME_CHARSET', 'utf-8') gzip = setting('AWS_IS_GZIPPED', False) preload_metadata = setting('AWS_PRELOAD_METADATA', False) gzip_content_types = setting('GZIP_CONTENT_TYPES', ( 'text/css', 'application/javascript', 'application/x-javascript', )) url_protocol = setting('AWS_S3_URL_PROTOCOL', 'http:') host = setting('AWS_S3_HOST', S3Connection.DefaultHost) use_ssl = setting('AWS_S3_USE_SSL', True) port = setting('AWS_S3_PORT', None) # The max amount of memory a returned file can take up before being # rolled over into a temporary file on disk. Default is 0: Do not roll over. max_memory_size = setting('AWS_S3_MAX_MEMORY_SIZE', 0) def __init__(self, acl=None, bucket=None, **settings): # check if some of the settings we've provided as class attributes # need to be overwritten with values passed in here for name, value in settings.items(): if hasattr(self, name): setattr(self, name, value) # For backward-compatibility of old differing parameter names if acl is not None: self.default_acl = acl if bucket is not None: self.bucket_name = bucket self.location = (self.location or '').lstrip('/') # Backward-compatibility: given the anteriority of the SECURE_URL setting # we fall back to https if specified in order to avoid the construction # of unsecure urls. if self.secure_urls: self.url_protocol = 'https:' self._entries = {} self._bucket = None self._connection = None if not self.access_key and not self.secret_key: self.access_key, self.secret_key = self._get_access_keys() @property def connection(self): if self._connection is None: self._connection = self.connection_class( self.access_key, self.secret_key, is_secure=self.use_ssl, calling_format=self.calling_format, host=self.host, port=self.port, ) return self._connection @property def bucket(self): """ Get the current bucket. If there is no current bucket object create it. """ if self._bucket is None: self._bucket = self._get_or_create_bucket(self.bucket_name) return self._bucket @property def entries(self): """ Get the locally cached files for the bucket. """ if self.preload_metadata and not self._entries: self._entries = dict((self._decode_name(entry.key), entry) for entry in self.bucket.list(prefix=self.location)) return self._entries def _get_access_keys(self): """ Gets the access keys to use when accessing S3. If none are provided to the class in the constructor or in the settings then get them from the environment variables. """ def lookup_env(names): for name in names: value = os.environ.get(name) if value: return value access_key = self.access_key or lookup_env(self.access_key_names) secret_key = self.secret_key or lookup_env(self.secret_key_names) return access_key, secret_key def _get_or_create_bucket(self, name): """ Retrieves a bucket if it exists, otherwise creates it. """ try: return self.connection.get_bucket(name, validate=self.auto_create_bucket) except self.connection_response_error: if self.auto_create_bucket: bucket = self.connection.create_bucket(name) bucket.set_acl(self.bucket_acl) return bucket raise ImproperlyConfigured("Bucket %s does not exist. Buckets " "can be automatically created by " "setting AWS_AUTO_CREATE_BUCKET to " "``True``." % name) def _clean_name(self, name): """ Cleans the name so that Windows style paths work """ # Normalize Windows style paths clean_name = posixpath.normpath(name).replace('\\', '/') # os.path.normpath() can strip trailing slashes so we implement # a workaround here. if name.endswith('/') and not clean_name.endswith('/'): # Add a trailing slash as it was stripped. return clean_name + '/' else: return clean_name def _normalize_name(self, name): """ Normalizes the name so that paths like /path/to/ignored/../something.txt work. We check to make sure that the path pointed to is not outside the directory specified by the LOCATION setting. """ try: return safe_join(self.location, name) except ValueError: raise SuspiciousOperation("Attempted access to '%s' denied." % name) def _encode_name(self, name): return smart_str(name, encoding=self.file_name_charset) def _decode_name(self, name): return force_unicode(name, encoding=self.file_name_charset) def _compress_content(self, content): """Gzip a given string content.""" zbuf = StringIO() zfile = GzipFile(mode='wb', compresslevel=6, fileobj=zbuf) try: zfile.write(content.read()) finally: zfile.close() zbuf.seek(0) content.file = zbuf content.seek(0) return content def _open(self, name, mode='rb'): name = self._normalize_name(self._clean_name(name)) f = self.file_class(name, mode, self) if not f.key: raise IOError('File does not exist: %s' % name) return f def _save(self, name, content): cleaned_name = self._clean_name(name) name = self._normalize_name(cleaned_name) headers = self.headers.copy() content_type = getattr(content, 'content_type', mimetypes.guess_type(name)[0] or self.key_class.DefaultContentType) # setting the content_type in the key object is not enough. headers.update({'Content-Type': content_type}) if self.gzip and content_type in self.gzip_content_types: content = self._compress_content(content) headers.update({'Content-Encoding': 'gzip'}) content.name = cleaned_name encoded_name = self._encode_name(name) key = self.bucket.get_key(encoded_name) if not key: key = self.bucket.new_key(encoded_name) if self.preload_metadata: self._entries[encoded_name] = key key.set_metadata('Content-Type', content_type) self._save_content(key, content, headers=headers) return cleaned_name def _save_content(self, key, content, headers): # only pass backwards incompatible arguments if they vary from the default kwargs = {} if self.encryption: kwargs['encrypt_key'] = self.encryption key.set_contents_from_file(content, headers=headers, policy=self.default_acl, reduced_redundancy=self.reduced_redundancy, rewind=True, **kwargs) def delete(self, name): name = self._normalize_name(self._clean_name(name)) self.bucket.delete_key(self._encode_name(name)) def exists(self, name): name = self._normalize_name(self._clean_name(name)) if self.entries: return name in self.entries k = self.bucket.new_key(self._encode_name(name)) return k.exists() def listdir(self, name): name = self._normalize_name(self._clean_name(name)) # for the bucket.list and logic below name needs to end in / # But for the root path "" we leave it as an empty string if name and not name.endswith('/'): name += '/' dirlist = self.bucket.list(self._encode_name(name)) files = [] dirs = set() base_parts = name.split("/")[:-1] for item in dirlist: parts = item.name.split("/") parts = parts[len(base_parts):] if len(parts) == 1: # File files.append(parts[0]) elif len(parts) > 1: # Directory dirs.add(parts[0]) return list(dirs), files def size(self, name): name = self._normalize_name(self._clean_name(name)) if self.entries: entry = self.entries.get(name) if entry: return entry.size return 0 return self.bucket.get_key(self._encode_name(name)).size def modified_time(self, name): name = self._normalize_name(self._clean_name(name)) entry = self.entries.get(name) # only call self.bucket.get_key() if the key is not found # in the preloaded metadata. if entry is None: entry = self.bucket.get_key(self._encode_name(name)) # Parse the last_modified string to a local datetime object. return parse_ts_extended(entry.last_modified) def url(self, name, headers=None, response_headers=None): # Preserve the trailing slash after normalizing the path. name = self._normalize_name(self._clean_name(name)) if self.custom_domain: return "%s//%s/%s" % (self.url_protocol, self.custom_domain, filepath_to_uri(name)) return self.connection.generate_url(self.querystring_expire, method='GET', bucket=self.bucket.name, key=self._encode_name(name), headers=headers, query_auth=self.querystring_auth, force_http=not self.secure_urls, response_headers=response_headers) def get_available_name(self, name): """ Overwrite existing file with the same name. """ if self.file_overwrite: name = self._clean_name(name) return name return super(S3BotoStorage, self).get_available_name(name)