+# Cumulus: Efficient Filesystem Backup to the Cloud
+# Copyright (C) 2008-2010 The Cumulus Developers
+# See the AUTHORS file for a list of contributors.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""Amazon S3 storage backend. Uses a URL of the form s3://BUCKET/PATH/."""
+
import os, sys, tempfile
import boto
+from boto.exception import S3ResponseError
from boto.s3.bucket import Bucket
from boto.s3.key import Key
import cumulus.store
+def throw_notfound(method):
+ """Decorator to convert a 404 error into a cumulus.store.NoutFoundError."""
+ def f(*args, **kwargs):
+ try:
+ return method(*args, **kwargs)
+ except S3ResponseError as e:
+ if e.status == 404:
+ print "Got a 404:", e
+ raise cumulus.store.NotFoundError(e)
+ else:
+ raise
+ return f
+
class S3Store(cumulus.store.Store):
- def __init__(self, bucket, prefix):
+ def __init__(self, url, **kw):
+ # Old versions of the Python urlparse library will take a URL like
+ # s3://bucket/path/ and include the bucket with the path, while new
+ # versions (2.6 and later) treat it as the netloc (which seems more
+ # correct).
+ #
+ # But, so that we can work with either behavior, for now just combine
+ # the netloc and path together before we do any further processing
+ # (which will then split the combined path apart into a bucket and path
+ # again). If we didn't want to support Python 2.5, this would be
+ # easier as we could just use the netloc as the bucket directly.
+ path = self.netloc + '/' + self.path
+ (bucket, prefix) = path.lstrip("/").split("/", 1)
self.conn = boto.connect_s3(is_secure=False)
self.bucket = self.conn.create_bucket(bucket)
- while prefix.endswith("/"): prefix = prefix[:-1]
- self.prefix = prefix
+ self.prefix = prefix.strip("/")
+ self.scan_cache = {}
- def _get_key(self, type, name):
+ def _get_key(self, path):
k = Key(self.bucket)
- k.key = "%s/%s/%s" % (self.prefix, type, name)
+ k.key = "%s/%s" % (self.prefix, path)
return k
- def list(self, type):
- prefix = "%s/%s/" % (self.prefix, type)
+ @throw_notfound
+ def scan(self, path):
+ prefix = "%s/%s/" % (self.prefix, path)
+ for i in self.bucket.list(prefix):
+ assert i.key.startswith(prefix)
+ self.scan_cache[i.key] = i
+
+ @throw_notfound
+ def list(self, path):
+ prefix = "%s/%s/" % (self.prefix, path)
for i in self.bucket.list(prefix):
assert i.key.startswith(prefix)
yield i.key[len(prefix):]
- def get(self, type, name):
+ @throw_notfound
+ def get(self, path):
fp = tempfile.TemporaryFile()
- k = self._get_key(type, name)
+ k = self._get_key(path)
k.get_file(fp)
fp.seek(0)
return fp
- def put(self, type, name, fp):
- k = self._get_key(type, name)
- k.send_file(fp)
+ @throw_notfound
+ def put(self, path, fp):
+ k = self._get_key(path)
+ k.set_contents_from_file(fp)
- def delete(self, type, name):
- self.bucket.delete_key("%s/%s/%s" % (self.prefix, type, name))
+ @throw_notfound
+ def delete(self, path):
+ self.bucket.delete_key("%s/%s" % (self.prefix, path))
+
+ def stat(self, path):
+ path = "%s/%s" % (self.prefix, path)
+ if path in self.scan_cache:
+ k = self.scan_cache[path]
+ else:
+ k = self.bucket.get_key(path)
+ if k is None:
+ raise cumulus.store.NotFoundError
- def stat(self, type, name):
- k = self.bucket.get_key("%s/%s/%s" % (self.prefix, type, name))
return {'size': int(k.size)}
+
+Store = S3Store
projects / cumulus.git / blobdiff