-#\r
-# Copyright (c) 2011 Greek Research and Technology Network\r
-#\r
-\r
-from functools import wraps\r
-\r
-from time import time\r
-from wsgiref.handlers import format_date_time\r
-\r
-from django.conf import settings\r
-from django.http import HttpResponse\r
-\r
-from pithos.api.faults import Fault, BadRequest, ServiceUnavailable\r
-\r
-import datetime\r
-import logging\r
-\r
-def format_meta_key(k):\r
- """\r
- Convert underscores to dashes and capitalize intra-dash strings.\r
- """\r
- return '-'.join([x.capitalize() for x in k.replace('_', '-').split('-')])\r
-\r
-def get_meta(request, prefix):\r
- """\r
- Get all prefix-* request headers in a dict. Reformat keys with format_meta_key().\r
- """\r
- prefix = 'HTTP_' + prefix.upper().replace('-', '_')\r
- return dict([(format_meta_key(k[5:]), v) for k, v in request.META.iteritems() if k.startswith(prefix)])\r
-\r
-def get_range(request):\r
- """\r
- Parse a Range header from the request.\r
- Either returns None, or an (offset, length) tuple.\r
- If no offset is defined offset equals 0.\r
- If no length is defined length is None.\r
- """\r
- \r
- range = request.GET.get('range')\r
- if not range:\r
- return None\r
- \r
- range = range.replace(' ', '')\r
- if not range.startswith('bytes='):\r
- return None\r
- \r
- parts = range.split('-')\r
- if len(parts) != 2:\r
- return None\r
- \r
- offset, length = parts\r
- if offset == '' and length == '':\r
- return None\r
- \r
- if offset != '':\r
- try:\r
- offset = int(offset)\r
- except ValueError:\r
- return None\r
- else:\r
- offset = 0\r
- \r
- if length != '':\r
- try:\r
- length = int(length)\r
- except ValueError:\r
- return None\r
- else:\r
- length = None\r
- \r
- return (offset, length)\r
-\r
-def update_response_headers(request, response):\r
- if request.serialization == 'xml':\r
- response['Content-Type'] = 'application/xml; charset=UTF-8'\r
- elif request.serialization == 'json':\r
- response['Content-Type'] = 'application/json; charset=UTF-8'\r
- else:\r
- response['Content-Type'] = 'text/plain; charset=UTF-8'\r
-\r
- if settings.TEST:\r
- response['Date'] = format_date_time(time())\r
-\r
-def render_fault(request, fault):\r
- response = HttpResponse(status = fault.code)\r
- update_response_headers(request, response)\r
- return response\r
-\r
-def request_serialization(request, format_allowed=False):\r
- """\r
- Return the serialization format requested.\r
- \r
- Valid formats are 'text' and 'json', 'xml' if `format_allowed` is True.\r
- """\r
- \r
- if not format_allowed:\r
- return 'text'\r
- \r
- format = request.GET.get('format')\r
- if format == 'json':\r
- return 'json'\r
- elif format == 'xml':\r
- return 'xml'\r
- \r
- for item in request.META.get('HTTP_ACCEPT', '').split(','):\r
- accept, sep, rest = item.strip().partition(';')\r
- if accept == 'text/plain':\r
- return 'text'\r
- elif accept == 'application/json':\r
- return 'json'\r
- elif accept == 'application/xml' or accept == 'text/xml':\r
- return 'xml'\r
- \r
- return 'text'\r
-\r
-def api_method(http_method = None, format_allowed = False):\r
- """\r
- Decorator function for views that implement an API method.\r
- """\r
- \r
- def decorator(func):\r
- @wraps(func)\r
- def wrapper(request, *args, **kwargs):\r
- try:\r
- if http_method and request.method != http_method:\r
- raise BadRequest('Method not allowed.')\r
-\r
- # The args variable may contain up to (account, container, object).\r
- if len(args) > 1 and len(args[1]) > 256:\r
- raise BadRequest('Container name too large.')\r
- if len(args) > 2 and len(args[2]) > 1024:\r
- raise BadRequest('Object name too large.')\r
- \r
- # Fill in custom request variables.\r
- request.serialization = request_serialization(request, format_allowed)\r
- # TODO: Authenticate.\r
- request.user = "test"\r
- \r
- response = func(request, *args, **kwargs)\r
- update_response_headers(request, response)\r
- return response\r
- except Fault, fault:\r
- return render_fault(request, fault)\r
- except BaseException, e:\r
- logging.exception('Unexpected error: %s' % e)\r
- fault = ServiceUnavailable('Unexpected error')\r
- return render_fault(request, fault)\r
- return wrapper\r
- return decorator\r
+# Copyright 2011 GRNET S.A. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or
+# without modification, are permitted provided that the following
+# conditions are met:
+#
+# 1. Redistributions of source code must retain the above
+# copyright notice, this list of conditions and the following
+# disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following
+# disclaimer in the documentation and/or other materials
+# provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
+# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+# The views and conclusions contained in the software and
+# documentation are those of the authors and should not be
+# interpreted as representing official policies, either expressed
+# or implied, of GRNET S.A.
+
+from functools import wraps
+from time import time
+from traceback import format_exc
+from wsgiref.handlers import format_date_time
+from binascii import hexlify, unhexlify
+
+from django.conf import settings
+from django.http import HttpResponse
+from django.utils import simplejson as json
+from django.utils.http import http_date, parse_etags
+from django.utils.encoding import smart_str
+
+from pithos.api.compat import parse_http_date_safe, parse_http_date
+from pithos.api.faults import (Fault, NotModified, BadRequest, Unauthorized, ItemNotFound,
+ Conflict, LengthRequired, PreconditionFailed, RangeNotSatisfiable,
+ ServiceUnavailable)
+from pithos.backends import backend
+from pithos.backends.base import NotAllowedError
+
+import datetime
+import logging
+import re
+import hashlib
+import uuid
+
+
+logger = logging.getLogger(__name__)
+
+
+def rename_meta_key(d, old, new):
+ if old not in d:
+ return
+ d[new] = d[old]
+ del(d[old])
+
+def printable_header_dict(d):
+ """Format a meta dictionary for printing out json/xml.
+
+ Convert all keys to lower case and replace dashes with underscores.
+ Format 'last_modified' timestamp.
+ """
+
+ d['last_modified'] = datetime.datetime.fromtimestamp(int(d['last_modified'])).isoformat()
+ return dict([(k.lower().replace('-', '_'), v) for k, v in d.iteritems()])
+
+def format_header_key(k):
+ """Convert underscores to dashes and capitalize intra-dash strings."""
+ return '-'.join([x.capitalize() for x in k.replace('_', '-').split('-')])
+
+def get_header_prefix(request, prefix):
+ """Get all prefix-* request headers in a dict. Reformat keys with format_header_key()."""
+
+ prefix = 'HTTP_' + prefix.upper().replace('-', '_')
+ # TODO: Document or remove '~' replacing.
+ return dict([(format_header_key(k[5:]), v.replace('~', '')) for k, v in request.META.iteritems() if k.startswith(prefix) and len(k) > len(prefix)])
+
+def get_account_headers(request):
+ meta = get_header_prefix(request, 'X-Account-Meta-')
+ groups = {}
+ for k, v in get_header_prefix(request, 'X-Account-Group-').iteritems():
+ n = k[16:].lower()
+ if '-' in n or '_' in n:
+ raise BadRequest('Bad characters in group name')
+ groups[n] = v.replace(' ', '').split(',')
+ if '' in groups[n]:
+ groups[n].remove('')
+ return meta, groups
+
+def put_account_headers(response, meta, groups):
+ if 'count' in meta:
+ response['X-Account-Container-Count'] = meta['count']
+ if 'bytes' in meta:
+ response['X-Account-Bytes-Used'] = meta['bytes']
+ response['Last-Modified'] = http_date(int(meta['modified']))
+ for k in [x for x in meta.keys() if x.startswith('X-Account-Meta-')]:
+ response[smart_str(k, strings_only=True)] = smart_str(meta[k], strings_only=True)
+ if 'until_timestamp' in meta:
+ response['X-Account-Until-Timestamp'] = http_date(int(meta['until_timestamp']))
+ for k, v in groups.iteritems():
+ k = smart_str(k, strings_only=True)
+ k = format_header_key('X-Account-Group-' + k)
+ v = smart_str(','.join(v), strings_only=True)
+ response[k] = v
+
+def get_container_headers(request):
+ meta = get_header_prefix(request, 'X-Container-Meta-')
+ policy = dict([(k[19:].lower(), v.replace(' ', '')) for k, v in get_header_prefix(request, 'X-Container-Policy-').iteritems()])
+ return meta, policy
+
+def put_container_headers(response, meta, policy):
+ if 'count' in meta:
+ response['X-Container-Object-Count'] = meta['count']
+ if 'bytes' in meta:
+ response['X-Container-Bytes-Used'] = meta['bytes']
+ response['Last-Modified'] = http_date(int(meta['modified']))
+ for k in [x for x in meta.keys() if x.startswith('X-Container-Meta-')]:
+ response[smart_str(k, strings_only=True)] = smart_str(meta[k], strings_only=True)
+ l = [smart_str(x, strings_only=True) for x in meta['object_meta'] if x.startswith('X-Object-Meta-')]
+ response['X-Container-Object-Meta'] = ','.join([x[14:] for x in l])
+ response['X-Container-Block-Size'] = backend.block_size
+ response['X-Container-Block-Hash'] = backend.hash_algorithm
+ if 'until_timestamp' in meta:
+ response['X-Container-Until-Timestamp'] = http_date(int(meta['until_timestamp']))
+ for k, v in policy.iteritems():
+ response[smart_str(format_header_key('X-Container-Policy-' + k), strings_only=True)] = smart_str(v, strings_only=True)
+
+def get_object_headers(request):
+ meta = get_header_prefix(request, 'X-Object-Meta-')
+ if request.META.get('CONTENT_TYPE'):
+ meta['Content-Type'] = request.META['CONTENT_TYPE']
+ if request.META.get('HTTP_CONTENT_ENCODING'):
+ meta['Content-Encoding'] = request.META['HTTP_CONTENT_ENCODING']
+ if request.META.get('HTTP_CONTENT_DISPOSITION'):
+ meta['Content-Disposition'] = request.META['HTTP_CONTENT_DISPOSITION']
+ if request.META.get('HTTP_X_OBJECT_MANIFEST'):
+ meta['X-Object-Manifest'] = request.META['HTTP_X_OBJECT_MANIFEST']
+ return meta, get_sharing(request), get_public(request)
+
+def put_object_headers(response, meta, restricted=False):
+ response['ETag'] = meta['hash']
+ response['Content-Length'] = meta['bytes']
+ response['Content-Type'] = meta.get('Content-Type', 'application/octet-stream')
+ response['Last-Modified'] = http_date(int(meta['modified']))
+ if not restricted:
+ response['X-Object-Modified-By'] = smart_str(meta['modified_by'], strings_only=True)
+ response['X-Object-Version'] = meta['version']
+ response['X-Object-Version-Timestamp'] = http_date(int(meta['version_timestamp']))
+ for k in [x for x in meta.keys() if x.startswith('X-Object-Meta-')]:
+ response[smart_str(k, strings_only=True)] = smart_str(meta[k], strings_only=True)
+ for k in ('Content-Encoding', 'Content-Disposition', 'X-Object-Manifest',
+ 'X-Object-Sharing', 'X-Object-Shared-By', 'X-Object-Allowed-To',
+ 'X-Object-Public'):
+ if k in meta:
+ response[k] = smart_str(meta[k], strings_only=True)
+ else:
+ for k in ('Content-Encoding', 'Content-Disposition'):
+ if k in meta:
+ response[k] = meta[k]
+
+def update_manifest_meta(request, v_account, meta):
+ """Update metadata if the object has an X-Object-Manifest."""
+
+ if 'X-Object-Manifest' in meta:
+ hash = ''
+ bytes = 0
+ try:
+ src_container, src_name = split_container_object_string('/' + meta['X-Object-Manifest'])
+ objects = backend.list_objects(request.user, v_account, src_container, prefix=src_name, virtual=False)
+ for x in objects:
+ src_meta = backend.get_object_meta(request.user, v_account, src_container, x[0], x[1])
+ hash += src_meta['hash']
+ bytes += src_meta['bytes']
+ except:
+ # Ignore errors.
+ return
+ meta['bytes'] = bytes
+ md5 = hashlib.md5()
+ md5.update(hash)
+ meta['hash'] = md5.hexdigest().lower()
+
+def update_sharing_meta(request, permissions, v_account, v_container, v_object, meta):
+ if permissions is None:
+ return
+ allowed, perm_path, perms = permissions
+ if len(perms) == 0:
+ return
+ ret = []
+ r = ','.join(perms.get('read', []))
+ if r:
+ ret.append('read=' + r)
+ w = ','.join(perms.get('write', []))
+ if w:
+ ret.append('write=' + w)
+ meta['X-Object-Sharing'] = '; '.join(ret)
+ if '/'.join((v_account, v_container, v_object)) != perm_path:
+ meta['X-Object-Shared-By'] = perm_path
+ if request.user != v_account:
+ meta['X-Object-Allowed-To'] = allowed
+
+def update_public_meta(public, meta):
+ if not public:
+ return
+ meta['X-Object-Public'] = public
+
+def validate_modification_preconditions(request, meta):
+ """Check that the modified timestamp conforms with the preconditions set."""
+
+ if 'modified' not in meta:
+ return # TODO: Always return?
+
+ if_modified_since = request.META.get('HTTP_IF_MODIFIED_SINCE')
+ if if_modified_since is not None:
+ if_modified_since = parse_http_date_safe(if_modified_since)
+ if if_modified_since is not None and int(meta['modified']) <= if_modified_since:
+ raise NotModified('Resource has not been modified')
+
+ if_unmodified_since = request.META.get('HTTP_IF_UNMODIFIED_SINCE')
+ if if_unmodified_since is not None:
+ if_unmodified_since = parse_http_date_safe(if_unmodified_since)
+ if if_unmodified_since is not None and int(meta['modified']) > if_unmodified_since:
+ raise PreconditionFailed('Resource has been modified')
+
+def validate_matching_preconditions(request, meta):
+ """Check that the ETag conforms with the preconditions set."""
+
+ hash = meta.get('hash', None)
+
+ if_match = request.META.get('HTTP_IF_MATCH')
+ if if_match is not None:
+ if hash is None:
+ raise PreconditionFailed('Resource does not exist')
+ if if_match != '*' and hash not in [x.lower() for x in parse_etags(if_match)]:
+ raise PreconditionFailed('Resource ETag does not match')
+
+ if_none_match = request.META.get('HTTP_IF_NONE_MATCH')
+ if if_none_match is not None:
+ # TODO: If this passes, must ignore If-Modified-Since header.
+ if hash is not None:
+ if if_none_match == '*' or hash in [x.lower() for x in parse_etags(if_none_match)]:
+ # TODO: Continue if an If-Modified-Since header is present.
+ if request.method in ('HEAD', 'GET'):
+ raise NotModified('Resource ETag matches')
+ raise PreconditionFailed('Resource exists or ETag matches')
+
+def split_container_object_string(s):
+ if not len(s) > 0 or s[0] != '/':
+ raise ValueError
+ s = s[1:]
+ pos = s.find('/')
+ if pos == -1:
+ raise ValueError
+ return s[:pos], s[(pos + 1):]
+
+def copy_or_move_object(request, v_account, src_container, src_name, dest_container, dest_name, move=False):
+ """Copy or move an object."""
+
+ meta, permissions, public = get_object_headers(request)
+ src_version = request.META.get('HTTP_X_SOURCE_VERSION')
+ try:
+ if move:
+ version_id = backend.move_object(request.user, v_account, src_container, src_name, dest_container, dest_name, meta, False, permissions)
+ else:
+ version_id = backend.copy_object(request.user, v_account, src_container, src_name, dest_container, dest_name, meta, False, permissions, src_version)
+ except NotAllowedError:
+ raise Unauthorized('Access denied')
+ except (NameError, IndexError):
+ raise ItemNotFound('Container or object does not exist')
+ except ValueError:
+ raise BadRequest('Invalid sharing header')
+ except AttributeError, e:
+ raise Conflict(json.dumps(e.data))
+ if public is not None:
+ try:
+ backend.update_object_public(request.user, v_account, dest_container, dest_name, public)
+ except NotAllowedError:
+ raise Unauthorized('Access denied')
+ except NameError:
+ raise ItemNotFound('Object does not exist')
+ return version_id
+
+def get_int_parameter(p):
+ if p is not None:
+ try:
+ p = int(p)
+ except ValueError:
+ return None
+ if p < 0:
+ return None
+ return p
+
+def get_content_length(request):
+ content_length = get_int_parameter(request.META.get('CONTENT_LENGTH'))
+ if content_length is None:
+ raise LengthRequired('Missing or invalid Content-Length header')
+ return content_length
+
+def get_range(request, size):
+ """Parse a Range header from the request.
+
+ Either returns None, when the header is not existent or should be ignored,
+ or a list of (offset, length) tuples - should be further checked.
+ """
+
+ ranges = request.META.get('HTTP_RANGE', '').replace(' ', '')
+ if not ranges.startswith('bytes='):
+ return None
+
+ ret = []
+ for r in (x.strip() for x in ranges[6:].split(',')):
+ p = re.compile('^(?P<offset>\d*)-(?P<upto>\d*)$')
+ m = p.match(r)
+ if not m:
+ return None
+ offset = m.group('offset')
+ upto = m.group('upto')
+ if offset == '' and upto == '':
+ return None
+
+ if offset != '':
+ offset = int(offset)
+ if upto != '':
+ upto = int(upto)
+ if offset > upto:
+ return None
+ ret.append((offset, upto - offset + 1))
+ else:
+ ret.append((offset, size - offset))
+ else:
+ length = int(upto)
+ ret.append((size - length, length))
+
+ return ret
+
+def get_content_range(request):
+ """Parse a Content-Range header from the request.
+
+ Either returns None, when the header is not existent or should be ignored,
+ or an (offset, length, total) tuple - check as length, total may be None.
+ Returns (None, None, None) if the provided range is '*/*'.
+ """
+
+ ranges = request.META.get('HTTP_CONTENT_RANGE', '')
+ if not ranges:
+ return None
+
+ p = re.compile('^bytes (?P<offset>\d+)-(?P<upto>\d*)/(?P<total>(\d+|\*))$')
+ m = p.match(ranges)
+ if not m:
+ if ranges == 'bytes */*':
+ return (None, None, None)
+ return None
+ offset = int(m.group('offset'))
+ upto = m.group('upto')
+ total = m.group('total')
+ if upto != '':
+ upto = int(upto)
+ else:
+ upto = None
+ if total != '*':
+ total = int(total)
+ else:
+ total = None
+ if (upto is not None and offset > upto) or \
+ (total is not None and offset >= total) or \
+ (total is not None and upto is not None and upto >= total):
+ return None
+
+ if upto is None:
+ length = None
+ else:
+ length = upto - offset + 1
+ return (offset, length, total)
+
+def get_sharing(request):
+ """Parse an X-Object-Sharing header from the request.
+
+ Raises BadRequest on error.
+ """
+
+ permissions = request.META.get('HTTP_X_OBJECT_SHARING')
+ if permissions is None:
+ return None
+
+ # TODO: Document or remove '~' replacing.
+ permissions = permissions.replace('~', '')
+
+ ret = {}
+ permissions = permissions.replace(' ', '')
+ if permissions == '':
+ return ret
+ for perm in (x for x in permissions.split(';')):
+ if perm.startswith('read='):
+ ret['read'] = list(set([v.replace(' ','').lower() for v in perm[5:].split(',')]))
+ if '' in ret['read']:
+ ret['read'].remove('')
+ if '*' in ret['read']:
+ ret['read'] = ['*']
+ if len(ret['read']) == 0:
+ raise BadRequest('Bad X-Object-Sharing header value')
+ elif perm.startswith('write='):
+ ret['write'] = list(set([v.replace(' ','').lower() for v in perm[6:].split(',')]))
+ if '' in ret['write']:
+ ret['write'].remove('')
+ if '*' in ret['write']:
+ ret['write'] = ['*']
+ if len(ret['write']) == 0:
+ raise BadRequest('Bad X-Object-Sharing header value')
+ else:
+ raise BadRequest('Bad X-Object-Sharing header value')
+
+ # Keep duplicates only in write list.
+ dups = [x for x in ret.get('read', []) if x in ret.get('write', []) and x != '*']
+ if dups:
+ for x in dups:
+ ret['read'].remove(x)
+ if len(ret['read']) == 0:
+ del(ret['read'])
+
+ return ret
+
+def get_public(request):
+ """Parse an X-Object-Public header from the request.
+
+ Raises BadRequest on error.
+ """
+
+ public = request.META.get('HTTP_X_OBJECT_PUBLIC')
+ if public is None:
+ return None
+
+ public = public.replace(' ', '').lower()
+ if public == 'true':
+ return True
+ elif public == 'false' or public == '':
+ return False
+ raise BadRequest('Bad X-Object-Public header value')
+
+def raw_input_socket(request):
+ """Return the socket for reading the rest of the request."""
+
+ server_software = request.META.get('SERVER_SOFTWARE')
+ if server_software and server_software.startswith('mod_python'):
+ return request._req
+ if 'wsgi.input' in request.environ:
+ return request.environ['wsgi.input']
+ raise ServiceUnavailable('Unknown server software')
+
+MAX_UPLOAD_SIZE = 10 * (1024 * 1024) # 10MB
+
+def socket_read_iterator(request, length=0, blocksize=4096):
+ """Return a maximum of blocksize data read from the socket in each iteration.
+
+ Read up to 'length'. If 'length' is negative, will attempt a chunked read.
+ The maximum ammount of data read is controlled by MAX_UPLOAD_SIZE.
+ """
+
+ sock = raw_input_socket(request)
+ if length < 0: # Chunked transfers
+ # Small version (server does the dechunking).
+ if request.environ.get('mod_wsgi.input_chunked', None):
+ while length < MAX_UPLOAD_SIZE:
+ data = sock.read(blocksize)
+ if data == '':
+ return
+ yield data
+ raise BadRequest('Maximum size is reached')
+
+ # Long version (do the dechunking).
+ data = ''
+ while length < MAX_UPLOAD_SIZE:
+ # Get chunk size.
+ if hasattr(sock, 'readline'):
+ chunk_length = sock.readline()
+ else:
+ chunk_length = ''
+ while chunk_length[-1:] != '\n':
+ chunk_length += sock.read(1)
+ chunk_length.strip()
+ pos = chunk_length.find(';')
+ if pos >= 0:
+ chunk_length = chunk_length[:pos]
+ try:
+ chunk_length = int(chunk_length, 16)
+ except Exception, e:
+ raise BadRequest('Bad chunk size') # TODO: Change to something more appropriate.
+ # Check if done.
+ if chunk_length == 0:
+ if len(data) > 0:
+ yield data
+ return
+ # Get the actual data.
+ while chunk_length > 0:
+ chunk = sock.read(min(chunk_length, blocksize))
+ chunk_length -= len(chunk)
+ if length > 0:
+ length += len(chunk)
+ data += chunk
+ if len(data) >= blocksize:
+ ret = data[:blocksize]
+ data = data[blocksize:]
+ yield ret
+ sock.read(2) # CRLF
+ raise BadRequest('Maximum size is reached')
+ else:
+ if length > MAX_UPLOAD_SIZE:
+ raise BadRequest('Maximum size is reached')
+ while length > 0:
+ data = sock.read(min(length, blocksize))
+ length -= len(data)
+ yield data
+
+class ObjectWrapper(object):
+ """Return the object's data block-per-block in each iteration.
+
+ Read from the object using the offset and length provided in each entry of the range list.
+ """
+
+ def __init__(self, ranges, sizes, hashmaps, boundary):
+ self.ranges = ranges
+ self.sizes = sizes
+ self.hashmaps = hashmaps
+ self.boundary = boundary
+ self.size = sum(self.sizes)
+
+ self.file_index = 0
+ self.block_index = 0
+ self.block_hash = -1
+ self.block = ''
+
+ self.range_index = -1
+ self.offset, self.length = self.ranges[0]
+
+ def __iter__(self):
+ return self
+
+ def part_iterator(self):
+ if self.length > 0:
+ # Get the file for the current offset.
+ file_size = self.sizes[self.file_index]
+ while self.offset >= file_size:
+ self.offset -= file_size
+ self.file_index += 1
+ file_size = self.sizes[self.file_index]
+
+ # Get the block for the current position.
+ self.block_index = int(self.offset / backend.block_size)
+ if self.block_hash != self.hashmaps[self.file_index][self.block_index]:
+ self.block_hash = self.hashmaps[self.file_index][self.block_index]
+ try:
+ self.block = backend.get_block(self.block_hash)
+ except NameError:
+ raise ItemNotFound('Block does not exist')
+
+ # Get the data from the block.
+ bo = self.offset % backend.block_size
+ bl = min(self.length, len(self.block) - bo)
+ data = self.block[bo:bo + bl]
+ self.offset += bl
+ self.length -= bl
+ return data
+ else:
+ raise StopIteration
+
+ def next(self):
+ if len(self.ranges) == 1:
+ return self.part_iterator()
+ if self.range_index == len(self.ranges):
+ raise StopIteration
+ try:
+ if self.range_index == -1:
+ raise StopIteration
+ return self.part_iterator()
+ except StopIteration:
+ self.range_index += 1
+ out = []
+ if self.range_index < len(self.ranges):
+ # Part header.
+ self.offset, self.length = self.ranges[self.range_index]
+ self.file_index = 0
+ if self.range_index > 0:
+ out.append('')
+ out.append('--' + self.boundary)
+ out.append('Content-Range: bytes %d-%d/%d' % (self.offset, self.offset + self.length - 1, self.size))
+ out.append('Content-Transfer-Encoding: binary')
+ out.append('')
+ out.append('')
+ return '\r\n'.join(out)
+ else:
+ # Footer.
+ out.append('')
+ out.append('--' + self.boundary + '--')
+ out.append('')
+ return '\r\n'.join(out)
+
+def object_data_response(request, sizes, hashmaps, meta, public=False):
+ """Get the HttpResponse object for replying with the object's data."""
+
+ # Range handling.
+ size = sum(sizes)
+ ranges = get_range(request, size)
+ if ranges is None:
+ ranges = [(0, size)]
+ ret = 200
+ else:
+ check = [True for offset, length in ranges if
+ length <= 0 or length > size or
+ offset < 0 or offset >= size or
+ offset + length > size]
+ if len(check) > 0:
+ raise RangeNotSatisfiable('Requested range exceeds object limits')
+ ret = 206
+ if_range = request.META.get('HTTP_IF_RANGE')
+ if if_range:
+ try:
+ # Modification time has passed instead.
+ last_modified = parse_http_date(if_range)
+ if last_modified != meta['modified']:
+ ranges = [(0, size)]
+ ret = 200
+ except ValueError:
+ if if_range != meta['hash']:
+ ranges = [(0, size)]
+ ret = 200
+
+ if ret == 206 and len(ranges) > 1:
+ boundary = uuid.uuid4().hex
+ else:
+ boundary = ''
+ wrapper = ObjectWrapper(ranges, sizes, hashmaps, boundary)
+ response = HttpResponse(wrapper, status=ret)
+ put_object_headers(response, meta, public)
+ if ret == 206:
+ if len(ranges) == 1:
+ offset, length = ranges[0]
+ response['Content-Length'] = length # Update with the correct length.
+ response['Content-Range'] = 'bytes %d-%d/%d' % (offset, offset + length - 1, size)
+ else:
+ del(response['Content-Length'])
+ response['Content-Type'] = 'multipart/byteranges; boundary=%s' % (boundary,)
+ return response
+
+def put_object_block(hashmap, data, offset):
+ """Put one block of data at the given offset."""
+
+ bi = int(offset / backend.block_size)
+ bo = offset % backend.block_size
+ bl = min(len(data), backend.block_size - bo)
+ if bi < len(hashmap):
+ hashmap[bi] = backend.update_block(hashmap[bi], data[:bl], bo)
+ else:
+ hashmap.append(backend.put_block(('\x00' * bo) + data[:bl]))
+ return bl # Return ammount of data written.
+
+def hashmap_hash(hashmap):
+ """Produce the root hash, treating the hashmap as a Merkle-like tree."""
+
+ def subhash(d):
+ h = hashlib.new(backend.hash_algorithm)
+ h.update(d)
+ return h.digest()
+
+ if len(hashmap) == 0:
+ return hexlify(subhash(''))
+ if len(hashmap) == 1:
+ return hashmap[0]
+
+ s = 2
+ while s < len(hashmap):
+ s = s * 2
+ h = [unhexlify(x) for x in hashmap]
+ h += [('\x00' * len(h[0]))] * (s - len(hashmap))
+ while len(h) > 1:
+ h = [subhash(h[x] + h[x + 1]) for x in range(0, len(h), 2)]
+ return hexlify(h[0])
+
+def update_response_headers(request, response):
+ if request.serialization == 'xml':
+ response['Content-Type'] = 'application/xml; charset=UTF-8'
+ elif request.serialization == 'json':
+ response['Content-Type'] = 'application/json; charset=UTF-8'
+ elif not response['Content-Type']:
+ response['Content-Type'] = 'text/plain; charset=UTF-8'
+
+ if not response.has_header('Content-Length') and not (response.has_header('Content-Type') and response['Content-Type'].startswith('multipart/byteranges')):
+ response['Content-Length'] = len(response.content)
+
+ if settings.TEST:
+ response['Date'] = format_date_time(time())
+
+def render_fault(request, fault):
+ if settings.DEBUG or settings.TEST:
+ fault.details = format_exc(fault)
+
+ request.serialization = 'text'
+ data = '\n'.join((fault.message, fault.details)) + '\n'
+ response = HttpResponse(data, status=fault.code)
+ update_response_headers(request, response)
+ return response
+
+def request_serialization(request, format_allowed=False):
+ """Return the serialization format requested.
+
+ Valid formats are 'text' and 'json', 'xml' if 'format_allowed' is True.
+ """
+
+ if not format_allowed:
+ return 'text'
+
+ format = request.GET.get('format')
+ if format == 'json':
+ return 'json'
+ elif format == 'xml':
+ return 'xml'
+
+ for item in request.META.get('HTTP_ACCEPT', '').split(','):
+ accept, sep, rest = item.strip().partition(';')
+ if accept == 'application/json':
+ return 'json'
+ elif accept == 'application/xml' or accept == 'text/xml':
+ return 'xml'
+
+ return 'text'
+
+def api_method(http_method=None, format_allowed=False):
+ """Decorator function for views that implement an API method."""
+
+ def decorator(func):
+ @wraps(func)
+ def wrapper(request, *args, **kwargs):
+ try:
+ if http_method and request.method != http_method:
+ raise BadRequest('Method not allowed.')
+
+ # The args variable may contain up to (account, container, object).
+ if len(args) > 1 and len(args[1]) > 256:
+ raise BadRequest('Container name too large.')
+ if len(args) > 2 and len(args[2]) > 1024:
+ raise BadRequest('Object name too large.')
+
+ # Fill in custom request variables.
+ request.serialization = request_serialization(request, format_allowed)
+
+ response = func(request, *args, **kwargs)
+ update_response_headers(request, response)
+ return response
+ except Fault, fault:
+ return render_fault(request, fault)
+ except BaseException, e:
+ logger.exception('Unexpected error: %s' % e)
+ fault = ServiceUnavailable('Unexpected error')
+ return render_fault(request, fault)
+ return wrapper
+ return decorator