/usr/lib/python2.7/dist-packages/swift/common/middleware/slo.py is in python-swift 2.7.0-0ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 | # Copyright (c) 2013 OpenStack Foundation
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
Middleware that will provide Static Large Object (SLO) support.
This feature is very similar to Dynamic Large Object (DLO) support in that
it allows the user to upload many objects concurrently and afterwards
download them as a single object. It is different in that it does not rely
on eventually consistent container listings to do so. Instead, a user
defined manifest of the object segments is used.
----------------------
Uploading the Manifest
----------------------
After the user has uploaded the objects to be concatenated, a manifest is
uploaded. The request must be a PUT with the query parameter::
?multipart-manifest=put
The body of this request will be an ordered list of segment descriptions in
JSON format. The data to be supplied for each segment is:
=========== ========================================================
Key Description
=========== ========================================================
path the path to the segment object (not including account)
/container/object_name
etag the ETag given back when the segment object was PUT,
or null
size_bytes the size of the complete segment object in
bytes, or null
range (optional) the (inclusive) range within the object to
use as a segment. If omitted, the entire object is used.
=========== ========================================================
The format of the list will be:
.. code::
[{"path": "/cont/object",
"etag": "etagoftheobjectsegment",
"size_bytes": 10485760,
"range": "1048576-2097151"}, ...]
The number of object segments is limited to a configurable amount, default
1000. Each segment must be at least 1 byte. On upload, the middleware will
head every segment passed in to verify:
1. the segment exists (i.e. the HEAD was successful);
2. the segment meets minimum size requirements;
3. if the user provided a non-null etag, the etag matches;
4. if the user provided a non-null size_bytes, the size_bytes matches; and
5. if the user provided a range, it is a singular, syntactically correct range
that is satisfiable given the size of the object.
Note that the etag and size_bytes keys are still required; this acts as a guard
against user errors such as typos. If any of the objects fail to verify (not
found, size/etag mismatch, below minimum size, invalid range) then the user
will receive a 4xx error response. If everything does match, the user will
receive a 2xx response and the SLO object is ready for downloading.
Behind the scenes, on success, a json manifest generated from the user input is
sent to object servers with an extra "X-Static-Large-Object: True" header
and a modified Content-Type. The items in this manifest will include the etag
and size_bytes for each segment, regardless of whether the client specified
them for verification. The parameter: swift_bytes=$total_size will be
appended to the existing Content-Type, where total_size is the sum of all
the included segments' size_bytes. This extra parameter will be hidden from
the user.
Manifest files can reference objects in separate containers, which will improve
concurrent upload speed. Objects can be referenced by multiple manifests. The
segments of a SLO manifest can even be other SLO manifests. Treat them as any
other object i.e., use the Etag and Content-Length given on the PUT of the
sub-SLO in the manifest to the parent SLO.
-------------------
Range Specification
-------------------
Users now have the ability to specify ranges for SLO segments.
Users can now include an optional 'range' field in segment descriptions
to specify which bytes from the underlying object should be used for the
segment data. Only one range may be specified per segment.
.. note::
The 'etag' and 'size_bytes' fields still describe the backing object as a
whole.
If a user uploads this manifest:
.. code::
[{"path": "/con/obj_seg_1", "etag": null, "size_bytes": 2097152,
"range": "0-1048576"},
{"path": "/con/obj_seg_2", "etag": null, "size_bytes": 2097152,
"range": "512-1550000"},
{"path": "/con/obj_seg_1", "etag": null, "size_bytes": 2097152,
"range": "-2048"}]
The segment will consist of the first 1048576 bytes of /con/obj_seg_1,
followed by bytes 513 through 1550000 (inclusive) of /con/obj_seg_2, and
finally bytes 2095104 through 2097152 (i.e., the last 2048 bytes) of
/con/obj_seg_1.
.. note::
The minimum sized range is 1 byte. This is the same as the minimum
segment size.
-------------------------
Retrieving a Large Object
-------------------------
A GET request to the manifest object will return the concatenation of the
objects from the manifest much like DLO. If any of the segments from the
manifest are not found or their Etag/Content Length have changed since upload,
the connection will drop. In this case a 409 Conflict will be logged in the
proxy logs and the user will receive incomplete results. Note that this will be
enforced regardless of whether the user perfomed per-segment validation during
upload.
The headers from this GET or HEAD request will return the metadata attached
to the manifest object itself with some exceptions::
Content-Length: the total size of the SLO (the sum of the sizes of
the segments in the manifest)
X-Static-Large-Object: True
Etag: the etag of the SLO (generated the same way as DLO)
A GET request with the query parameter::
?multipart-manifest=get
will return a transformed version of the original manifest, containing
additional fields and different key names.
A GET request with the query parameters::
?multipart-manifest=get&format=raw
will return the contents of the original manifest as it was sent by the client.
The main purpose for both calls is solely debugging.
When the manifest object is uploaded you are more or less guaranteed that
every segment in the manifest exists and matched the specifications.
However, there is nothing that prevents the user from breaking the
SLO download by deleting/replacing a segment referenced in the manifest. It is
left to the user to use caution in handling the segments.
-----------------------
Deleting a Large Object
-----------------------
A DELETE request will just delete the manifest object itself.
A DELETE with a query parameter::
?multipart-manifest=delete
will delete all the segments referenced in the manifest and then the manifest
itself. The failure response will be similar to the bulk delete middleware.
------------------------
Modifying a Large Object
------------------------
PUTs / POSTs will work as expected, PUTs will just overwrite the manifest
object for example.
------------------
Container Listings
------------------
In a container listing the size listed for SLO manifest objects will be the
total_size of the concatenated segments in the manifest. The overall
X-Container-Bytes-Used for the container (and subsequently for the account)
will not reflect total_size of the manifest but the actual size of the json
data stored. The reason for this somewhat confusing discrepancy is we want the
container listing to reflect the size of the manifest object when it is
downloaded. We do not, however, want to count the bytes-used twice (for both
the manifest and the segments it's referring to) in the container and account
metadata which can be used for stats purposes.
"""
from six.moves import range
from datetime import datetime
import json
import mimetypes
import re
import six
from six import BytesIO
from hashlib import md5
from swift.common.exceptions import ListingIterError, SegmentError
from swift.common.swob import Request, HTTPBadRequest, HTTPServerError, \
HTTPMethodNotAllowed, HTTPRequestEntityTooLarge, HTTPLengthRequired, \
HTTPOk, HTTPPreconditionFailed, HTTPException, HTTPNotFound, \
HTTPUnauthorized, HTTPConflict, HTTPRequestedRangeNotSatisfiable,\
Response, Range
from swift.common.utils import get_logger, config_true_value, \
get_valid_utf8_str, override_bytes_from_content_type, split_path, \
register_swift_info, RateLimitedIterator, quote, close_if_possible, \
closing_if_possible
from swift.common.request_helpers import SegmentedIterable
from swift.common.constraints import check_utf8, MAX_BUFFERED_SLO_SEGMENTS
from swift.common.http import HTTP_NOT_FOUND, HTTP_UNAUTHORIZED, is_success
from swift.common.wsgi import WSGIContext, make_subrequest
from swift.common.middleware.bulk import get_response_body, \
ACCEPTABLE_FORMATS, Bulk
DEFAULT_RATE_LIMIT_UNDER_SIZE = 1024 * 1024 # 1 MiB
DEFAULT_MAX_MANIFEST_SEGMENTS = 1000
DEFAULT_MAX_MANIFEST_SIZE = 1024 * 1024 * 2 # 2 MiB
REQUIRED_SLO_KEYS = set(['path', 'etag', 'size_bytes'])
OPTIONAL_SLO_KEYS = set(['range'])
ALLOWED_SLO_KEYS = REQUIRED_SLO_KEYS | OPTIONAL_SLO_KEYS
def parse_and_validate_input(req_body, req_path):
"""
Given a request body, parses it and returns a list of dictionaries.
The output structure is nearly the same as the input structure, but it
is not an exact copy. Given a valid input dictionary `d_in`, its
corresponding output dictionary `d_out` will be as follows:
* d_out['etag'] == d_in['etag']
* d_out['path'] == d_in['path']
* d_in['size_bytes'] can be a string ("12") or an integer (12), but
d_out['size_bytes'] is an integer.
* (optional) d_in['range'] is a string of the form "M-N", "M-", or
"-N", where M and N are non-negative integers. d_out['range'] is the
corresponding swob.Range object. If d_in does not have a key
'range', neither will d_out.
:raises: HTTPException on parse errors or semantic errors (e.g. bogus
JSON structure, syntactically invalid ranges)
:returns: a list of dictionaries on success
"""
try:
parsed_data = json.loads(req_body)
except ValueError:
raise HTTPBadRequest("Manifest must be valid JSON.\n")
if not isinstance(parsed_data, list):
raise HTTPBadRequest("Manifest must be a list.\n")
# If we got here, req_path refers to an object, so this won't ever raise
# ValueError.
vrs, account, _junk = split_path(req_path, 3, 3, True)
errors = []
for seg_index, seg_dict in enumerate(parsed_data):
if not isinstance(seg_dict, dict):
errors.append("Index %d: not a JSON object" % seg_index)
continue
missing_keys = [k for k in REQUIRED_SLO_KEYS if k not in seg_dict]
if missing_keys:
errors.append(
"Index %d: missing keys %s"
% (seg_index,
", ".join('"%s"' % (mk,) for mk in sorted(missing_keys))))
continue
extraneous_keys = [k for k in seg_dict if k not in ALLOWED_SLO_KEYS]
if extraneous_keys:
errors.append(
"Index %d: extraneous keys %s"
% (seg_index,
", ".join('"%s"' % (ek,)
for ek in sorted(extraneous_keys))))
continue
if not isinstance(seg_dict['path'], basestring):
errors.append("Index %d: \"path\" must be a string" % seg_index)
continue
if not (seg_dict['etag'] is None or
isinstance(seg_dict['etag'], basestring)):
errors.append(
"Index %d: \"etag\" must be a string or null" % seg_index)
continue
if '/' not in seg_dict['path'].strip('/'):
errors.append(
"Index %d: path does not refer to an object. Path must be of "
"the form /container/object." % seg_index)
continue
seg_size = seg_dict['size_bytes']
if seg_size is not None:
try:
seg_size = int(seg_size)
seg_dict['size_bytes'] = seg_size
except (TypeError, ValueError):
errors.append("Index %d: invalid size_bytes" % seg_index)
continue
if seg_size < 1:
errors.append("Index %d: too small; each segment must be "
"at least 1 byte."
% (seg_index,))
continue
obj_path = '/'.join(['', vrs, account, seg_dict['path'].lstrip('/')])
if req_path == quote(obj_path):
errors.append(
"Index %d: manifest must not include itself as a segment"
% seg_index)
continue
if seg_dict.get('range'):
try:
seg_dict['range'] = Range('bytes=%s' % seg_dict['range'])
except ValueError:
errors.append("Index %d: invalid range" % seg_index)
continue
if len(seg_dict['range'].ranges) > 1:
errors.append("Index %d: multiple ranges (only one allowed)"
% seg_index)
continue
# If the user *told* us the object's size, we can check range
# satisfiability right now. If they lied about the size, we'll
# fail that validation later.
if (seg_size is not None and
len(seg_dict['range'].ranges_for_length(seg_size)) != 1):
errors.append("Index %d: unsatisfiable range" % seg_index)
continue
if errors:
error_message = "".join(e + "\n" for e in errors)
raise HTTPBadRequest(error_message,
headers={"Content-Type": "text/plain"})
return parsed_data
class SloPutContext(WSGIContext):
def __init__(self, slo, slo_etag):
super(SloPutContext, self).__init__(slo.app)
self.slo_etag = '"' + slo_etag.hexdigest() + '"'
def handle_slo_put(self, req, start_response):
app_resp = self._app_call(req.environ)
for i in range(len(self._response_headers)):
if self._response_headers[i][0].lower() == 'etag':
self._response_headers[i] = ('Etag', self.slo_etag)
break
start_response(self._response_status,
self._response_headers,
self._response_exc_info)
return app_resp
class SloGetContext(WSGIContext):
max_slo_recursion_depth = 10
def __init__(self, slo):
self.slo = slo
self.first_byte = None
self.last_byte = None
super(SloGetContext, self).__init__(slo.app)
def _fetch_sub_slo_segments(self, req, version, acc, con, obj):
"""
Fetch the submanifest, parse it, and return it.
Raise exception on failures.
"""
sub_req = make_subrequest(
req.environ, path='/'.join(['', version, acc, con, obj]),
method='GET',
headers={'x-auth-token': req.headers.get('x-auth-token')},
agent=('%(orig)s ' + 'SLO MultipartGET'), swift_source='SLO')
sub_resp = sub_req.get_response(self.slo.app)
if not is_success(sub_resp.status_int):
close_if_possible(sub_resp.app_iter)
raise ListingIterError(
'ERROR: while fetching %s, GET of submanifest %s '
'failed with status %d' % (req.path, sub_req.path,
sub_resp.status_int))
try:
with closing_if_possible(sub_resp.app_iter):
return json.loads(''.join(sub_resp.app_iter))
except ValueError as err:
raise ListingIterError(
'ERROR: while fetching %s, JSON-decoding of submanifest %s '
'failed with %s' % (req.path, sub_req.path, err))
def _segment_length(self, seg_dict):
"""
Returns the number of bytes that will be fetched from the specified
segment on a plain GET request for this SLO manifest.
"""
seg_range = seg_dict.get('range')
if seg_range is not None:
# The range is of the form N-M, where N and M are both positive
# decimal integers. We know this because this middleware is the
# only thing that creates the SLO manifests stored in the
# cluster.
range_start, range_end = [int(x) for x in seg_range.split('-')]
return range_end - range_start + 1
else:
return int(seg_dict['bytes'])
def _segment_listing_iterator(self, req, version, account, segments,
recursion_depth=1):
for seg_dict in segments:
if config_true_value(seg_dict.get('sub_slo')):
override_bytes_from_content_type(seg_dict,
logger=self.slo.logger)
# We handle the range stuff here so that we can be smart about
# skipping unused submanifests. For example, if our first segment is a
# submanifest referencing 50 MiB total, but start_byte falls in
# the 51st MiB, then we can avoid fetching the first submanifest.
#
# If we were to make SegmentedIterable handle all the range
# calculations, we would be unable to make this optimization.
total_length = sum(self._segment_length(seg) for seg in segments)
if self.first_byte is None:
self.first_byte = 0
if self.last_byte is None:
self.last_byte = total_length - 1
last_sub_path = None
for seg_dict in segments:
seg_length = self._segment_length(seg_dict)
if self.first_byte >= seg_length:
# don't need any bytes from this segment
self.first_byte -= seg_length
self.last_byte -= seg_length
continue
if self.last_byte < 0:
# no bytes are needed from this or any future segment
break
seg_range = seg_dict.get('range')
if seg_range is None:
range_start, range_end = 0, seg_length - 1
else:
# We already validated and supplied concrete values
# for the range on upload
range_start, range_end = map(int, seg_range.split('-'))
if config_true_value(seg_dict.get('sub_slo')):
# do this check here so that we can avoid fetching this last
# manifest before raising the exception
if recursion_depth >= self.max_slo_recursion_depth:
raise ListingIterError("Max recursion depth exceeded")
sub_path = get_valid_utf8_str(seg_dict['name'])
sub_cont, sub_obj = split_path(sub_path, 2, 2, True)
if last_sub_path != sub_path:
sub_segments = self._fetch_sub_slo_segments(
req, version, account, sub_cont, sub_obj)
last_sub_path = sub_path
# Use the existing machinery to slice into the sub-SLO.
# This requires that we save off our current state, and
# restore at the other end.
orig_start, orig_end = self.first_byte, self.last_byte
self.first_byte = range_start + max(0, self.first_byte)
self.last_byte = min(range_end, range_start + self.last_byte)
for sub_seg_dict, sb, eb in self._segment_listing_iterator(
req, version, account, sub_segments,
recursion_depth=recursion_depth + 1):
yield sub_seg_dict, sb, eb
# Restore the first/last state
self.first_byte, self.last_byte = orig_start, orig_end
else:
if isinstance(seg_dict['name'], six.text_type):
seg_dict['name'] = seg_dict['name'].encode("utf-8")
yield (seg_dict,
max(0, self.first_byte) + range_start,
min(range_end, range_start + self.last_byte))
self.first_byte -= seg_length
self.last_byte -= seg_length
def _need_to_refetch_manifest(self, req):
"""
Just because a response shows that an object is a SLO manifest does not
mean that response's body contains the entire SLO manifest. If it
doesn't, we need to make a second request to actually get the whole
thing.
Note: this assumes that X-Static-Large-Object has already been found.
"""
if req.method == 'HEAD':
return True
response_status = int(self._response_status[:3])
# These are based on etag, and the SLO's etag is almost certainly not
# the manifest object's etag. Still, it's highly likely that the
# submitted If-None-Match won't match the manifest object's etag, so
# we can avoid re-fetching the manifest if we got a successful
# response.
if ((req.if_match or req.if_none_match) and
not is_success(response_status)):
return True
if req.range and response_status in (206, 416):
content_range = ''
for header, value in self._response_headers:
if header.lower() == 'content-range':
content_range = value
break
# e.g. Content-Range: bytes 0-14289/14290
match = re.match('bytes (\d+)-(\d+)/(\d+)$', content_range)
if not match:
# Malformed or missing, so we don't know what we got.
return True
first_byte, last_byte, length = [int(x) for x in match.groups()]
# If and only if we actually got back the full manifest body, then
# we can avoid re-fetching the object.
got_everything = (first_byte == 0 and last_byte == length - 1)
return not got_everything
return False
def handle_slo_get_or_head(self, req, start_response):
"""
Takes a request and a start_response callable and does the normal WSGI
thing with them. Returns an iterator suitable for sending up the WSGI
chain.
:param req: swob.Request object; is a GET or HEAD request aimed at
what may be a static large object manifest (or may not).
:param start_response: WSGI start_response callable
"""
resp_iter = self._app_call(req.environ)
# make sure this response is for a static large object manifest
for header, value in self._response_headers:
if (header.lower() == 'x-static-large-object' and
config_true_value(value)):
break
else:
# Not a static large object manifest. Just pass it through.
start_response(self._response_status,
self._response_headers,
self._response_exc_info)
return resp_iter
# Handle pass-through request for the manifest itself
if req.params.get('multipart-manifest') == 'get':
if req.params.get('format') == 'raw':
resp_iter = self.convert_segment_listing(
self._response_headers, resp_iter)
new_headers = []
for header, value in self._response_headers:
if header.lower() == 'content-type':
new_headers.append(('Content-Type',
'application/json; charset=utf-8'))
else:
new_headers.append((header, value))
self._response_headers = new_headers
start_response(self._response_status,
self._response_headers,
self._response_exc_info)
return resp_iter
if self._need_to_refetch_manifest(req):
req.environ['swift.non_client_disconnect'] = True
close_if_possible(resp_iter)
del req.environ['swift.non_client_disconnect']
get_req = make_subrequest(
req.environ, method='GET',
headers={'x-auth-token': req.headers.get('x-auth-token')},
agent=('%(orig)s ' + 'SLO MultipartGET'), swift_source='SLO')
resp_iter = self._app_call(get_req.environ)
# Any Content-Range from a manifest is almost certainly wrong for the
# full large object.
resp_headers = [(h, v) for h, v in self._response_headers
if not h.lower() == 'content-range']
response = self.get_or_head_response(
req, resp_headers, resp_iter)
return response(req.environ, start_response)
def convert_segment_listing(self, resp_headers, resp_iter):
"""
Converts the manifest data to match with the format
that was put in through ?multipart-manifest=put
:param resp_headers: response headers
:param resp_iter: a response iterable
"""
segments = self._get_manifest_read(resp_iter)
for seg_dict in segments:
seg_dict.pop('content_type', None)
seg_dict.pop('last_modified', None)
seg_dict.pop('sub_slo', None)
seg_dict['path'] = seg_dict.pop('name', None)
seg_dict['size_bytes'] = seg_dict.pop('bytes', None)
seg_dict['etag'] = seg_dict.pop('hash', None)
json_data = json.dumps(segments) # convert to string
if six.PY3:
json_data = json_data.encode('utf-8')
new_headers = []
for header, value in resp_headers:
if header.lower() == 'content-length':
new_headers.append(('Content-Length',
len(json_data)))
else:
new_headers.append((header, value))
self._response_headers = new_headers
return [json_data]
def _get_manifest_read(self, resp_iter):
with closing_if_possible(resp_iter):
resp_body = ''.join(resp_iter)
try:
segments = json.loads(resp_body)
except ValueError:
segments = []
return segments
def get_or_head_response(self, req, resp_headers, resp_iter):
segments = self._get_manifest_read(resp_iter)
etag = md5()
content_length = 0
for seg_dict in segments:
if seg_dict.get('range'):
etag.update('%s:%s;' % (seg_dict['hash'], seg_dict['range']))
else:
etag.update(seg_dict['hash'])
if config_true_value(seg_dict.get('sub_slo')):
override_bytes_from_content_type(
seg_dict, logger=self.slo.logger)
content_length += self._segment_length(seg_dict)
response_headers = [(h, v) for h, v in resp_headers
if h.lower() not in ('etag', 'content-length')]
response_headers.append(('Content-Length', str(content_length)))
response_headers.append(('Etag', '"%s"' % etag.hexdigest()))
if req.method == 'HEAD':
return self._manifest_head_response(req, response_headers)
else:
return self._manifest_get_response(
req, content_length, response_headers, segments)
def _manifest_head_response(self, req, response_headers):
return HTTPOk(request=req, headers=response_headers, body='',
conditional_response=True)
def _manifest_get_response(self, req, content_length, response_headers,
segments):
self.first_byte, self.last_byte = None, None
if req.range:
byteranges = req.range.ranges_for_length(content_length)
if len(byteranges) == 0:
return HTTPRequestedRangeNotSatisfiable(request=req)
elif len(byteranges) == 1:
self.first_byte, self.last_byte = byteranges[0]
# For some reason, swob.Range.ranges_for_length adds 1 to the
# last byte's position.
self.last_byte -= 1
else:
req.range = None
ver, account, _junk = req.split_path(3, 3, rest_with_last=True)
plain_listing_iter = self._segment_listing_iterator(
req, ver, account, segments)
def is_small_segment((seg_dict, start_byte, end_byte)):
start = 0 if start_byte is None else start_byte
end = int(seg_dict['bytes']) - 1 if end_byte is None else end_byte
is_small = (end - start + 1) < self.slo.rate_limit_under_size
return is_small
ratelimited_listing_iter = RateLimitedIterator(
plain_listing_iter,
self.slo.rate_limit_segments_per_sec,
limit_after=self.slo.rate_limit_after_segment,
ratelimit_if=is_small_segment)
# self._segment_listing_iterator gives us 3-tuples of (segment dict,
# start byte, end byte), but SegmentedIterable wants (obj path, etag,
# size, start byte, end byte), so we clean that up here
segment_listing_iter = (
("/{ver}/{acc}/{conobj}".format(
ver=ver, acc=account, conobj=seg_dict['name'].lstrip('/')),
seg_dict['hash'], int(seg_dict['bytes']),
start_byte, end_byte)
for seg_dict, start_byte, end_byte in ratelimited_listing_iter)
segmented_iter = SegmentedIterable(
req, self.slo.app, segment_listing_iter,
name=req.path, logger=self.slo.logger,
ua_suffix="SLO MultipartGET",
swift_source="SLO",
max_get_time=self.slo.max_get_time)
try:
segmented_iter.validate_first_segment()
except (ListingIterError, SegmentError):
# Copy from the SLO explanation in top of this file.
# If any of the segments from the manifest are not found or
# their Etag/Content Length no longer match the connection
# will drop. In this case a 409 Conflict will be logged in
# the proxy logs and the user will receive incomplete results.
return HTTPConflict(request=req)
response = Response(request=req, content_length=content_length,
headers=response_headers,
conditional_response=True,
app_iter=segmented_iter)
if req.range:
response.headers.pop('Etag')
return response
class StaticLargeObject(object):
"""
StaticLargeObject Middleware
See above for a full description.
The proxy logs created for any subrequests made will have swift.source set
to "SLO".
:param app: The next WSGI filter or app in the paste.deploy chain.
:param conf: The configuration dict for the middleware.
"""
def __init__(self, app, conf,
max_manifest_segments=DEFAULT_MAX_MANIFEST_SEGMENTS,
max_manifest_size=DEFAULT_MAX_MANIFEST_SIZE):
self.conf = conf
self.app = app
self.logger = get_logger(conf, log_route='slo')
self.max_manifest_segments = max_manifest_segments
self.max_manifest_size = max_manifest_size
self.max_get_time = int(self.conf.get('max_get_time', 86400))
self.rate_limit_under_size = int(self.conf.get(
'rate_limit_under_size', DEFAULT_RATE_LIMIT_UNDER_SIZE))
self.rate_limit_after_segment = int(self.conf.get(
'rate_limit_after_segment', '10'))
self.rate_limit_segments_per_sec = int(self.conf.get(
'rate_limit_segments_per_sec', '1'))
self.bulk_deleter = Bulk(app, {}, logger=self.logger)
def handle_multipart_get_or_head(self, req, start_response):
"""
Handles the GET or HEAD of a SLO manifest.
The response body (only on GET, of course) will consist of the
concatenation of the segments.
:params req: a swob.Request with a path referencing an object
:raises: HttpException on errors
"""
return SloGetContext(self).handle_slo_get_or_head(req, start_response)
def copy_hook(self, inner_hook):
def slo_hook(source_req, source_resp, sink_req):
x_slo = source_resp.headers.get('X-Static-Large-Object')
if (config_true_value(x_slo)
and source_req.params.get('multipart-manifest') != 'get'
and 'swift.post_as_copy' not in source_req.environ):
source_resp = SloGetContext(self).get_or_head_response(
source_req, source_resp.headers.items(),
source_resp.app_iter)
return inner_hook(source_req, source_resp, sink_req)
return slo_hook
def handle_multipart_put(self, req, start_response):
"""
Will handle the PUT of a SLO manifest.
Heads every object in manifest to check if is valid and if so will
save a manifest generated from the user input. Uses WSGIContext to
call self and start_response and returns a WSGI iterator.
:params req: a swob.Request with an obj in path
:raises: HttpException on errors
"""
try:
vrs, account, container, obj = req.split_path(1, 4, True)
except ValueError:
return self.app(req.environ, start_response)
if req.content_length > self.max_manifest_size:
raise HTTPRequestEntityTooLarge(
"Manifest File > %d bytes" % self.max_manifest_size)
if req.headers.get('X-Copy-From'):
raise HTTPMethodNotAllowed(
'Multipart Manifest PUTs cannot be COPY requests')
if req.content_length is None and \
req.headers.get('transfer-encoding', '').lower() != 'chunked':
raise HTTPLengthRequired(request=req)
parsed_data = parse_and_validate_input(
req.body_file.read(self.max_manifest_size),
req.path)
problem_segments = []
if len(parsed_data) > self.max_manifest_segments:
raise HTTPRequestEntityTooLarge(
'Number of segments must be <= %d' %
self.max_manifest_segments)
total_size = 0
out_content_type = req.accept.best_match(ACCEPTABLE_FORMATS)
if not out_content_type:
out_content_type = 'text/plain'
data_for_storage = []
slo_etag = md5()
last_obj_path = None
for index, seg_dict in enumerate(parsed_data):
obj_name = seg_dict['path']
if isinstance(obj_name, six.text_type):
obj_name = obj_name.encode('utf-8')
obj_path = '/'.join(['', vrs, account, obj_name.lstrip('/')])
new_env = req.environ.copy()
new_env['PATH_INFO'] = obj_path
new_env['REQUEST_METHOD'] = 'HEAD'
new_env['swift.source'] = 'SLO'
del(new_env['wsgi.input'])
del(new_env['QUERY_STRING'])
new_env['CONTENT_LENGTH'] = 0
new_env['HTTP_USER_AGENT'] = \
'%s MultipartPUT' % req.environ.get('HTTP_USER_AGENT')
if obj_path != last_obj_path:
last_obj_path = obj_path
head_seg_resp = \
Request.blank(obj_path, new_env).get_response(self)
if head_seg_resp.is_success:
segment_length = head_seg_resp.content_length
if seg_dict.get('range'):
# Since we now know the length, we can normalize the
# range. We know that there is exactly one range
# requested since we checked that earlier in
# parse_and_validate_input().
ranges = seg_dict['range'].ranges_for_length(
head_seg_resp.content_length)
if not ranges:
problem_segments.append([quote(obj_name),
'Unsatisfiable Range'])
elif ranges == [(0, head_seg_resp.content_length)]:
# Just one range, and it exactly matches the object.
# Why'd we do this again?
del seg_dict['range']
segment_length = head_seg_resp.content_length
else:
rng = ranges[0]
seg_dict['range'] = '%d-%d' % (rng[0], rng[1] - 1)
segment_length = rng[1] - rng[0]
if segment_length < 1:
problem_segments.append(
[quote(obj_name),
'Too small; each segment must be at least 1 byte.'])
total_size += segment_length
if seg_dict['size_bytes'] is not None and \
seg_dict['size_bytes'] != head_seg_resp.content_length:
problem_segments.append([quote(obj_name), 'Size Mismatch'])
if seg_dict['etag'] is None or \
seg_dict['etag'] == head_seg_resp.etag:
if seg_dict.get('range'):
slo_etag.update('%s:%s;' % (head_seg_resp.etag,
seg_dict['range']))
else:
slo_etag.update(head_seg_resp.etag)
else:
problem_segments.append([quote(obj_name), 'Etag Mismatch'])
if head_seg_resp.last_modified:
last_modified = head_seg_resp.last_modified
else:
# shouldn't happen
last_modified = datetime.now()
last_modified_formatted = \
last_modified.strftime('%Y-%m-%dT%H:%M:%S.%f')
seg_data = {'name': '/' + seg_dict['path'].lstrip('/'),
'bytes': head_seg_resp.content_length,
'hash': head_seg_resp.etag,
'content_type': head_seg_resp.content_type,
'last_modified': last_modified_formatted}
if seg_dict.get('range'):
seg_data['range'] = seg_dict['range']
if config_true_value(
head_seg_resp.headers.get('X-Static-Large-Object')):
seg_data['sub_slo'] = True
data_for_storage.append(seg_data)
else:
problem_segments.append([quote(obj_name),
head_seg_resp.status])
if problem_segments:
resp_body = get_response_body(
out_content_type, {}, problem_segments)
raise HTTPBadRequest(resp_body, content_type=out_content_type)
env = req.environ
if not env.get('CONTENT_TYPE'):
guessed_type, _junk = mimetypes.guess_type(req.path_info)
env['CONTENT_TYPE'] = guessed_type or 'application/octet-stream'
env['swift.content_type_overridden'] = True
env['CONTENT_TYPE'] += ";swift_bytes=%d" % total_size
env['HTTP_X_STATIC_LARGE_OBJECT'] = 'True'
json_data = json.dumps(data_for_storage)
if six.PY3:
json_data = json_data.encode('utf-8')
env['CONTENT_LENGTH'] = str(len(json_data))
env['wsgi.input'] = BytesIO(json_data)
slo_put_context = SloPutContext(self, slo_etag)
return slo_put_context.handle_slo_put(req, start_response)
def get_segments_to_delete_iter(self, req):
"""
A generator function to be used to delete all the segments and
sub-segments referenced in a manifest.
:params req: a swob.Request with an SLO manifest in path
:raises HTTPPreconditionFailed: on invalid UTF8 in request path
:raises HTTPBadRequest: on too many buffered sub segments and
on invalid SLO manifest path
"""
if not check_utf8(req.path_info):
raise HTTPPreconditionFailed(
request=req, body='Invalid UTF8 or contains NULL')
vrs, account, container, obj = req.split_path(4, 4, True)
segments = [{
'sub_slo': True,
'name': ('/%s/%s' % (container, obj)).decode('utf-8')}]
while segments:
if len(segments) > MAX_BUFFERED_SLO_SEGMENTS:
raise HTTPBadRequest(
'Too many buffered slo segments to delete.')
seg_data = segments.pop(0)
if seg_data.get('sub_slo'):
try:
segments.extend(
self.get_slo_segments(seg_data['name'], req))
except HTTPException as err:
# allow bulk delete response to report errors
seg_data['error'] = {'code': err.status_int,
'message': err.body}
# add manifest back to be deleted after segments
seg_data['sub_slo'] = False
segments.append(seg_data)
else:
seg_data['name'] = seg_data['name'].encode('utf-8')
yield seg_data
def get_slo_segments(self, obj_name, req):
"""
Performs a swob.Request and returns the SLO manifest's segments.
:raises HTTPServerError: on unable to load obj_name or
on unable to load the SLO manifest data.
:raises HTTPBadRequest: on not an SLO manifest
:raises HTTPNotFound: on SLO manifest not found
:returns: SLO manifest's segments
"""
vrs, account, _junk = req.split_path(2, 3, True)
new_env = req.environ.copy()
new_env['REQUEST_METHOD'] = 'GET'
del(new_env['wsgi.input'])
new_env['QUERY_STRING'] = 'multipart-manifest=get'
new_env['CONTENT_LENGTH'] = 0
new_env['HTTP_USER_AGENT'] = \
'%s MultipartDELETE' % new_env.get('HTTP_USER_AGENT')
new_env['swift.source'] = 'SLO'
new_env['PATH_INFO'] = (
'/%s/%s/%s' % (vrs, account, obj_name.lstrip('/'))
).encode('utf-8')
resp = Request.blank('', new_env).get_response(self.app)
if resp.is_success:
if config_true_value(resp.headers.get('X-Static-Large-Object')):
try:
return json.loads(resp.body)
except ValueError:
raise HTTPServerError('Unable to load SLO manifest')
else:
raise HTTPBadRequest('Not an SLO manifest')
elif resp.status_int == HTTP_NOT_FOUND:
raise HTTPNotFound('SLO manifest not found')
elif resp.status_int == HTTP_UNAUTHORIZED:
raise HTTPUnauthorized('401 Unauthorized')
else:
raise HTTPServerError('Unable to load SLO manifest or segment.')
def handle_multipart_delete(self, req):
"""
Will delete all the segments in the SLO manifest and then, if
successful, will delete the manifest file.
:params req: a swob.Request with an obj in path
:returns: swob.Response whose app_iter set to Bulk.handle_delete_iter
"""
req.headers['Content-Type'] = None # Ignore content-type from client
resp = HTTPOk(request=req)
out_content_type = req.accept.best_match(ACCEPTABLE_FORMATS)
if out_content_type:
resp.content_type = out_content_type
resp.app_iter = self.bulk_deleter.handle_delete_iter(
req, objs_to_delete=self.get_segments_to_delete_iter(req),
user_agent='MultipartDELETE', swift_source='SLO',
out_content_type=out_content_type)
return resp
def __call__(self, env, start_response):
"""
WSGI entry point
"""
req = Request(env)
try:
vrs, account, container, obj = req.split_path(4, 4, True)
except ValueError:
return self.app(env, start_response)
# install our COPY-callback hook
env['swift.copy_hook'] = self.copy_hook(
env.get('swift.copy_hook',
lambda src_req, src_resp, sink_req: src_resp))
try:
if req.method == 'PUT' and \
req.params.get('multipart-manifest') == 'put':
return self.handle_multipart_put(req, start_response)
if req.method == 'DELETE' and \
req.params.get('multipart-manifest') == 'delete':
return self.handle_multipart_delete(req)(env, start_response)
if req.method == 'GET' or req.method == 'HEAD':
return self.handle_multipart_get_or_head(req, start_response)
if 'X-Static-Large-Object' in req.headers:
raise HTTPBadRequest(
request=req,
body='X-Static-Large-Object is a reserved header. '
'To create a static large object add query param '
'multipart-manifest=put.')
except HTTPException as err_resp:
return err_resp(env, start_response)
return self.app(env, start_response)
def filter_factory(global_conf, **local_conf):
conf = global_conf.copy()
conf.update(local_conf)
max_manifest_segments = int(conf.get('max_manifest_segments',
DEFAULT_MAX_MANIFEST_SEGMENTS))
max_manifest_size = int(conf.get('max_manifest_size',
DEFAULT_MAX_MANIFEST_SIZE))
register_swift_info('slo',
max_manifest_segments=max_manifest_segments,
max_manifest_size=max_manifest_size,
# this used to be configurable; report it as 1 for
# clients that might still care
min_segment_size=1)
def slo_filter(app):
return StaticLargeObject(
app, conf,
max_manifest_segments=max_manifest_segments,
max_manifest_size=max_manifest_size)
return slo_filter
|