Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

file 1041 lines (918 sloc) 42.786 kb
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
# Copyright (c) 2006-2012 Mitch Garnaat http://garnaat.org/
# Copyright (c) 2012 Amazon.com, Inc. or its affiliates.
# Copyright (c) 2010 Google
# Copyright (c) 2008 rPath, Inc.
# Copyright (c) 2009 The Echo Nest Corporation
# Copyright (c) 2010, Eucalyptus Systems, Inc.
# Copyright (c) 2011, Nexenta Systems Inc.
# All rights reserved.
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish, dis-
# tribute, sublicense, and/or sell copies of the Software, and to permit
# persons to whom the Software is furnished to do so, subject to the fol-
# lowing conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL-
# ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
# SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
# IN THE SOFTWARE.

#
# Parts of this code were copied or derived from sample code supplied by AWS.
# The following notice applies to that code.
#
# This software code is made available "AS IS" without warranties of any
# kind. You may copy, display, modify and redistribute the software
# code either by itself or as incorporated into your code; provided that
# you do not remove any proprietary notices. Your use of this software
# code is at your own risk and you waive any claim against Amazon
# Digital Services, Inc. or its affiliates with respect to your use of
# this software code. (c) 2006 Amazon Digital Services, Inc. or its
# affiliates.

"""
Handles basic connections to AWS
"""

from __future__ import with_statement
import base64
import errno
import httplib
import os
import random
import re
import socket
import sys
import time
import urllib
import urlparse
import xml.sax
import copy

import auth
import auth_handler
import boto
import boto.utils
import boto.handler
import boto.cacerts

from boto import config, UserAgent
from boto.exception import BotoClientError
from boto.exception import BotoServerError
from boto.provider import Provider
from boto.resultset import ResultSet

HAVE_HTTPS_CONNECTION = False
try:
    import ssl
    from boto import https_connection
    # Google App Engine runs on Python 2.5 so doesn't have ssl.SSLError.
    if hasattr(ssl, 'SSLError'):
        HAVE_HTTPS_CONNECTION = True
except ImportError:
    pass

try:
    import threading
except ImportError:
    import dummy_threading as threading

ON_APP_ENGINE = all(key in os.environ for key in (
    'USER_IS_ADMIN', 'CURRENT_VERSION_ID', 'APPLICATION_ID'))

PORTS_BY_SECURITY = {True: 443,
                     False: 80}

DEFAULT_CA_CERTS_FILE = os.path.join(os.path.dirname(os.path.abspath(boto.cacerts.__file__ )), "cacerts.txt")


class HostConnectionPool(object):

    """
A pool of connections for one remote (host,is_secure).

When connections are added to the pool, they are put into a
pending queue. The _mexe method returns connections to the pool
before the response body has been read, so they connections aren't
ready to send another request yet. They stay in the pending queue
until they are ready for another request, at which point they are
returned to the pool of ready connections.

The pool of ready connections is an ordered list of
(connection,time) pairs, where the time is the time the connection
was returned from _mexe. After a certain period of time,
connections are considered stale, and discarded rather than being
reused. This saves having to wait for the connection to time out
if AWS has decided to close it on the other end because of
inactivity.

Thread Safety:

This class is used only fram ConnectionPool while it's mutex
is held.
"""

    def __init__(self):
        self.queue = []

    def size(self):
        """
Returns the number of connections in the pool for this host.
Some of the connections may still be in use, and may not be
ready to be returned by get().
"""
        return len(self.queue)

    def put(self, conn):
        """
Adds a connection to the pool, along with the time it was
added.
"""
        self.queue.append((conn, time.time()))

    def get(self):
        """
Returns the next connection in this pool that is ready to be
reused. Returns None of there aren't any.
"""
        # Discard ready connections that are too old.
        self.clean()

        # Return the first connection that is ready, and remove it
        # from the queue. Connections that aren't ready are returned
        # to the end of the queue with an updated time, on the
        # assumption that somebody is actively reading the response.
        for _ in range(len(self.queue)):
            (conn, _) = self.queue.pop(0)
            if self._conn_ready(conn):
                return conn
            else:
                self.put(conn)
        return None

    def _conn_ready(self, conn):
        """
There is a nice state diagram at the top of httplib.py. It
indicates that once the response headers have been read (which
_mexe does before adding the connection to the pool), a
response is attached to the connection, and it stays there
until it's done reading. This isn't entirely true: even after
the client is done reading, the response may be closed, but
not removed from the connection yet.

This is ugly, reading a private instance variable, but the
state we care about isn't available in any public methods.
"""
        if ON_APP_ENGINE:
            # Google AppEngine implementation of HTTPConnection doesn't contain
            # _HTTPConnection__response attribute. Moreover, it's not possible
            # to determine if given connection is ready. Reusing connections
            # simply doesn't make sense with App Engine urlfetch service.
            return False
        else:
            response = getattr(conn, '_HTTPConnection__response', None)
            return (response is None) or response.isclosed()

    def clean(self):
        """
Get rid of stale connections.
"""
        # Note that we do not close the connection here -- somebody
        # may still be reading from it.
        while len(self.queue) > 0 and self._pair_stale(self.queue[0]):
            self.queue.pop(0)

    def _pair_stale(self, pair):
        """
Returns true of the (connection,time) pair is too old to be
used.
"""
        (_conn, return_time) = pair
        now = time.time()
        return return_time + ConnectionPool.STALE_DURATION < now


class ConnectionPool(object):

    """
A connection pool that expires connections after a fixed period of
time. This saves time spent waiting for a connection that AWS has
timed out on the other end.

This class is thread-safe.
"""

    #
    # The amout of time between calls to clean.
    #

    CLEAN_INTERVAL = 5.0

    #
    # How long before a connection becomes "stale" and won't be reused
    # again. The intention is that this time is less that the timeout
    # period that AWS uses, so we'll never try to reuse a connection
    # and find that AWS is timing it out.
    #
    # Experimentation in July 2011 shows that AWS starts timing things
    # out after three minutes. The 60 seconds here is conservative so
    # we should never hit that 3-minute timout.
    #

    STALE_DURATION = 60.0

    def __init__(self):
        # Mapping from (host,is_secure) to HostConnectionPool.
        # If a pool becomes empty, it is removed.
        self.host_to_pool = {}
        # The last time the pool was cleaned.
        self.last_clean_time = 0.0
        self.mutex = threading.Lock()
        ConnectionPool.STALE_DURATION = \
            config.getfloat('Boto', 'connection_stale_duration',
                            ConnectionPool.STALE_DURATION)

    def __getstate__(self):
        pickled_dict = copy.copy(self.__dict__)
        pickled_dict['host_to_pool'] = {}
        del pickled_dict['mutex']
        return pickled_dict

    def __setstate__(self, dct):
        self.__init__()

    def size(self):
        """
Returns the number of connections in the pool.
"""
        return sum(pool.size() for pool in self.host_to_pool.values())

    def get_http_connection(self, host, is_secure):
        """
Gets a connection from the pool for the named host. Returns
None if there is no connection that can be reused. It's the caller's
responsibility to call close() on the connection when it's no longer
needed.
"""
        self.clean()
        with self.mutex:
            key = (host, is_secure)
            if key not in self.host_to_pool:
                return None
            return self.host_to_pool[key].get()

    def put_http_connection(self, host, is_secure, conn):
        """
Adds a connection to the pool of connections that can be
reused for the named host.
"""
        with self.mutex:
            key = (host, is_secure)
            if key not in self.host_to_pool:
                self.host_to_pool[key] = HostConnectionPool()
            self.host_to_pool[key].put(conn)

    def clean(self):
        """
Clean up the stale connections in all of the pools, and then
get rid of empty pools. Pools clean themselves every time a
connection is fetched; this cleaning takes care of pools that
aren't being used any more, so nothing is being gotten from
them.
"""
        with self.mutex:
            now = time.time()
            if self.last_clean_time + self.CLEAN_INTERVAL < now:
                to_remove = []
                for (host, pool) in self.host_to_pool.items():
                    pool.clean()
                    if pool.size() == 0:
                        to_remove.append(host)
                for host in to_remove:
                    del self.host_to_pool[host]
                self.last_clean_time = now


class HTTPRequest(object):

    def __init__(self, method, protocol, host, port, path, auth_path,
                 params, headers, body):
        """Represents an HTTP request.

:type method: string
:param method: The HTTP method name, 'GET', 'POST', 'PUT' etc.

:type protocol: string
:param protocol: The http protocol used, 'http' or 'https'.

:type host: string
:param host: Host to which the request is addressed. eg. abc.com

:type port: int
:param port: port on which the request is being sent. Zero means unset,
in which case default port will be chosen.

:type path: string
:param path: URL path that is being accessed.

:type auth_path: string
:param path: The part of the URL path used when creating the
authentication string.

:type params: dict
:param params: HTTP url query parameters, with key as name of
the param, and value as value of param.

:type headers: dict
:param headers: HTTP headers, with key as name of the header and value
as value of header.

:type body: string
:param body: Body of the HTTP request. If not present, will be None or
empty string ('').
"""
        self.method = method
        self.protocol = protocol
        self.host = host
        self.port = port
        self.path = path
        if auth_path is None:
            auth_path = path
        self.auth_path = auth_path
        self.params = params
        # chunked Transfer-Encoding should act only on PUT request.
        if headers and 'Transfer-Encoding' in headers and \
                headers['Transfer-Encoding'] == 'chunked' and \
                self.method != 'PUT':
            self.headers = headers.copy()
            del self.headers['Transfer-Encoding']
        else:
            self.headers = headers
        self.body = body

    def __str__(self):
        return (('method:(%s) protocol:(%s) host(%s) port(%s) path(%s) '
                 'params(%s) headers(%s) body(%s)') % (self.method,
                 self.protocol, self.host, self.port, self.path, self.params,
                 self.headers, self.body))

    def authorize(self, connection, **kwargs):
        for key in self.headers:
            val = self.headers[key]
            if isinstance(val, unicode):
                self.headers[key] = urllib.quote_plus(val.encode('utf-8'))

        connection._auth_handler.add_auth(self, **kwargs)

        self.headers['User-Agent'] = UserAgent
        # I'm not sure if this is still needed, now that add_auth is
        # setting the content-length for POST requests.
        if 'Content-Length' not in self.headers:
            if 'Transfer-Encoding' not in self.headers or \
                    self.headers['Transfer-Encoding'] != 'chunked':
                self.headers['Content-Length'] = str(len(self.body))


class HTTPResponse(httplib.HTTPResponse):

    def __init__(self, *args, **kwargs):
        httplib.HTTPResponse.__init__(self, *args, **kwargs)
        self._cached_response = ''

    def read(self, amt=None):
        """Read the response.

This method does not have the same behavior as
httplib.HTTPResponse.read. Instead, if this method is called with
no ``amt`` arg, then the response body will be cached. Subsequent
calls to ``read()`` with no args **will return the cached response**.

"""
        if amt is None:
            # The reason for doing this is that many places in boto call
            # response.read() and except to get the response body that they
            # can then process. To make sure this always works as they expect
            # we're caching the response so that multiple calls to read()
            # will return the full body. Note that this behavior only
            # happens if the amt arg is not specified.
            if not self._cached_response:
                self._cached_response = httplib.HTTPResponse.read(self)
            return self._cached_response
        else:
            return httplib.HTTPResponse.read(self, amt)


class AWSAuthConnection(object):
    def __init__(self, host, aws_access_key_id=None,
                 aws_secret_access_key=None,
                 is_secure=True, port=None, proxy=None, proxy_port=None,
                 proxy_user=None, proxy_pass=None, debug=0,
                 https_connection_factory=None, path='/',
                 provider='aws', security_token=None,
                 suppress_consec_slashes=True,
                 validate_certs=True):
        """
:type host: str
:param host: The host to make the connection to

:keyword str aws_access_key_id: Your AWS Access Key ID (provided by
Amazon). If none is specified, the value in your
``AWS_ACCESS_KEY_ID`` environmental variable is used.
:keyword str aws_secret_access_key: Your AWS Secret Access Key
(provided by Amazon). If none is specified, the value in your
``AWS_SECRET_ACCESS_KEY`` environmental variable is used.

:type is_secure: boolean
:param is_secure: Whether the connection is over SSL

:type https_connection_factory: list or tuple
:param https_connection_factory: A pair of an HTTP connection
factory and the exceptions to catch. The factory should have
a similar interface to L{httplib.HTTPSConnection}.

:param str proxy: Address/hostname for a proxy server

:type proxy_port: int
:param proxy_port: The port to use when connecting over a proxy

:type proxy_user: str
:param proxy_user: The username to connect with on the proxy

:type proxy_pass: str
:param proxy_pass: The password to use when connection over a proxy.

:type port: int
:param port: The port to use to connect

:type suppress_consec_slashes: bool
:param suppress_consec_slashes: If provided, controls whether
consecutive slashes will be suppressed in key paths.

:type validate_certs: bool
:param validate_certs: Controls whether SSL certificates
will be validated or not. Defaults to True.
"""
        self.suppress_consec_slashes = suppress_consec_slashes
        self.num_retries = 6
        # Override passed-in is_secure setting if value was defined in config.
        if config.has_option('Boto', 'is_secure'):
            is_secure = config.getboolean('Boto', 'is_secure')
        self.is_secure = is_secure
        # Whether or not to validate server certificates.
        # The default is now to validate certificates. This can be
        # overridden in the boto config file are by passing an
        # explicit validate_certs parameter to the class constructor.
        self.https_validate_certificates = config.getbool(
            'Boto', 'https_validate_certificates',
            validate_certs)
        if self.https_validate_certificates and not HAVE_HTTPS_CONNECTION:
            raise BotoClientError(
                    "SSL server certificate validation is enabled in boto "
                    "configuration, but Python dependencies required to "
                    "support this feature are not available. Certificate "
                    "validation is only supported when running under Python "
                    "2.6 or later.")
        self.ca_certificates_file = config.get_value(
                'Boto', 'ca_certificates_file', DEFAULT_CA_CERTS_FILE)
        self.handle_proxy(proxy, proxy_port, proxy_user, proxy_pass)
        # define exceptions from httplib that we want to catch and retry
        self.http_exceptions = (httplib.HTTPException, socket.error,
                                socket.gaierror, httplib.BadStatusLine)
        # define subclasses of the above that are not retryable.
        self.http_unretryable_exceptions = []
        if HAVE_HTTPS_CONNECTION:
            self.http_unretryable_exceptions.append(
                    https_connection.InvalidCertificateException)

        # define values in socket exceptions we don't want to catch
        self.socket_exception_values = (errno.EINTR,)
        if https_connection_factory is not None:
            self.https_connection_factory = https_connection_factory[0]
            self.http_exceptions += https_connection_factory[1]
        else:
            self.https_connection_factory = None
        if (is_secure):
            self.protocol = 'https'
        else:
            self.protocol = 'http'
        self.host = host
        self.path = path
        # if the value passed in for debug
        if not isinstance(debug, (int, long)):
            debug = 0
        self.debug = config.getint('Boto', 'debug', debug)
        if port:
            self.port = port
        else:
            self.port = PORTS_BY_SECURITY[is_secure]

        # Timeout used to tell httplib how long to wait for socket timeouts.
        # Default is to leave timeout unchanged, which will in turn result in
        # the socket's default global timeout being used. To specify a
        # timeout, set http_socket_timeout in Boto config. Regardless,
        # timeouts will only be applied if Python is 2.6 or greater.
        self.http_connection_kwargs = {}
        if (sys.version_info[0], sys.version_info[1]) >= (2, 6):
            if config.has_option('Boto', 'http_socket_timeout'):
                timeout = config.getint('Boto', 'http_socket_timeout')
                self.http_connection_kwargs['timeout'] = timeout

        if isinstance(provider, Provider):
            # Allow overriding Provider
            self.provider = provider
        else:
            self._provider_type = provider
            self.provider = Provider(self._provider_type,
                                     aws_access_key_id,
                                     aws_secret_access_key,
                                     security_token)

        # allow config file to override default host
        if self.provider.host:
            self.host = self.provider.host

        self._pool = ConnectionPool()
        self._connection = (self.server_name(), self.is_secure)
        self._last_rs = None
        self._auth_handler = auth.get_auth_handler(
              host, config, self.provider, self._required_auth_capability())
        if getattr(self, 'AuthServiceName', None) is not None:
            self.auth_service_name = self.AuthServiceName

    def __repr__(self):
        return '%s:%s' % (self.__class__.__name__, self.host)

    def _required_auth_capability(self):
        return []

    def _get_auth_service_name(self):
        return getattr(self._auth_handler, 'service_name')

    # For Sigv4, the auth_service_name/auth_region_name properties allow
    # the service_name/region_name to be explicitly set instead of being
    # derived from the endpoint url.
    def _set_auth_service_name(self, value):
        self._auth_handler.service_name = value
    auth_service_name = property(_get_auth_service_name, _set_auth_service_name)

    def _get_auth_region_name(self):
        return getattr(self._auth_handler, 'region_name')

    def _set_auth_region_name(self, value):
        self._auth_handler.region_name = value
    auth_region_name = property(_get_auth_region_name, _set_auth_region_name)

    def connection(self):
        return self.get_http_connection(*self._connection)
    connection = property(connection)

    def aws_access_key_id(self):
        return self.provider.access_key
    aws_access_key_id = property(aws_access_key_id)
    gs_access_key_id = aws_access_key_id
    access_key = aws_access_key_id

    def aws_secret_access_key(self):
        return self.provider.secret_key
    aws_secret_access_key = property(aws_secret_access_key)
    gs_secret_access_key = aws_secret_access_key
    secret_key = aws_secret_access_key

    def get_path(self, path='/'):
        # The default behavior is to suppress consecutive slashes for reasons
        # discussed at
        # https://groups.google.com/forum/#!topic/boto-dev/-ft0XPUy0y8
        # You can override that behavior with the suppress_consec_slashes param.
        if not self.suppress_consec_slashes:
            return self.path + re.sub('^/*', "", path)
        pos = path.find('?')
        if pos >= 0:
            params = path[pos:]
            path = path[:pos]
        else:
            params = None
        if path[-1] == '/':
            need_trailing = True
        else:
            need_trailing = False
        path_elements = self.path.split('/')
        path_elements.extend(path.split('/'))
        path_elements = [p for p in path_elements if p]
        path = '/' + '/'.join(path_elements)
        if path[-1] != '/' and need_trailing:
            path += '/'
        if params:
            path = path + params
        return path

    def server_name(self, port=None):
        if not port:
            port = self.port
        if port == 80:
            signature_host = self.host
        else:
            # This unfortunate little hack can be attributed to
            # a difference in the 2.6 version of httplib. In old
            # versions, it would append ":443" to the hostname sent
            # in the Host header and so we needed to make sure we
            # did the same when calculating the V2 signature. In 2.6
            # (and higher!)
            # it no longer does that. Hence, this kludge.
            if ((ON_APP_ENGINE and sys.version[:3] == '2.5') or
                    sys.version[:3] in ('2.6', '2.7')) and port == 443:
                signature_host = self.host
            else:
                signature_host = '%s:%d' % (self.host, port)
        return signature_host

    def handle_proxy(self, proxy, proxy_port, proxy_user, proxy_pass):
        self.proxy = proxy
        self.proxy_port = proxy_port
        self.proxy_user = proxy_user
        self.proxy_pass = proxy_pass
        if 'http_proxy' in os.environ and not self.proxy:
            pattern = re.compile(
                '(?:http://)?' \
                '(?:(?P<user>\w+):(?P<pass>.*)@)?' \
                '(?P<host>[\w\-\.]+)' \
                '(?::(?P<port>\d+))?'
            )
            match = pattern.match(os.environ['http_proxy'])
            if match:
                self.proxy = match.group('host')
                self.proxy_port = match.group('port')
                self.proxy_user = match.group('user')
                self.proxy_pass = match.group('pass')
        else:
            if not self.proxy:
                self.proxy = config.get_value('Boto', 'proxy', None)
            if not self.proxy_port:
                self.proxy_port = config.get_value('Boto', 'proxy_port', None)
            if not self.proxy_user:
                self.proxy_user = config.get_value('Boto', 'proxy_user', None)
            if not self.proxy_pass:
                self.proxy_pass = config.get_value('Boto', 'proxy_pass', None)

        if not self.proxy_port and self.proxy:
            print "http_proxy environment variable does not specify " \
                "a port, using default"
            self.proxy_port = self.port
        self.use_proxy = (self.proxy != None)

    def get_http_connection(self, host, is_secure):
        conn = self._pool.get_http_connection(host, is_secure)
        if conn is not None:
            return conn
        else:
            return self.new_http_connection(host, is_secure)

    def new_http_connection(self, host, is_secure):
        if self.use_proxy and not is_secure:
            host = '%s:%d' % (self.proxy, int(self.proxy_port))
        if host is None:
            host = self.server_name()
        if is_secure:
            boto.log.debug(
                    'establishing HTTPS connection: host=%s, kwargs=%s',
                    host, self.http_connection_kwargs)
            if self.use_proxy:
                connection = self.proxy_ssl(host, is_secure and 443 or 80)
            elif self.https_connection_factory:
                connection = self.https_connection_factory(host)
            elif self.https_validate_certificates and HAVE_HTTPS_CONNECTION:
                connection = https_connection.CertValidatingHTTPSConnection(
                        host, ca_certs=self.ca_certificates_file,
                        **self.http_connection_kwargs)
            else:
                connection = httplib.HTTPSConnection(host,
                        **self.http_connection_kwargs)
        else:
            boto.log.debug('establishing HTTP connection: kwargs=%s' %
                    self.http_connection_kwargs)
            if self.https_connection_factory:
                # even though the factory says https, this is too handy
                # to not be able to allow overriding for http also.
                connection = self.https_connection_factory(host,
                    **self.http_connection_kwargs)
            else:
                connection = httplib.HTTPConnection(host,
                    **self.http_connection_kwargs)
        if self.debug > 1:
            connection.set_debuglevel(self.debug)
        # self.connection must be maintained for backwards-compatibility
        # however, it must be dynamically pulled from the connection pool
        # set a private variable which will enable that
        if host.split(':')[0] == self.host and is_secure == self.is_secure:
            self._connection = (host, is_secure)
        # Set the response class of the http connection to use our custom
        # class.
        connection.response_class = HTTPResponse
        return connection

    def put_http_connection(self, host, is_secure, connection):
        self._pool.put_http_connection(host, is_secure, connection)

    def proxy_ssl(self, host=None, port=None):
        if host and port:
            host = '%s:%d' % (host, port)
        else:
            host = '%s:%d' % (self.host, self.port)
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        try:
            sock.connect((self.proxy, int(self.proxy_port)))
        except:
            raise
        boto.log.debug("Proxy connection: CONNECT %s HTTP/1.0\r\n", host)
        sock.sendall("CONNECT %s HTTP/1.0\r\n" % host)
        sock.sendall("User-Agent: %s\r\n" % UserAgent)
        if self.proxy_user and self.proxy_pass:
            for k, v in self.get_proxy_auth_header().items():
                sock.sendall("%s: %s\r\n" % (k, v))
            # See discussion about this config option at
            # https://groups.google.com/forum/?fromgroups#!topic/boto-dev/teenFvOq2Cc
            if config.getbool('Boto', 'send_crlf_after_proxy_auth_headers', False):
                sock.sendall("\r\n")
        else:
            sock.sendall("\r\n")
        resp = httplib.HTTPResponse(sock, strict=True, debuglevel=self.debug)
        resp.begin()

        if resp.status != 200:
            # Fake a socket error, use a code that make it obvious it hasn't
            # been generated by the socket library
            raise socket.error(-71,
                               "Error talking to HTTP proxy %s:%s: %s (%s)" %
                               (self.proxy, self.proxy_port,
                                resp.status, resp.reason))

        # We can safely close the response, it duped the original socket
        resp.close()

        h = httplib.HTTPConnection(host)

        if self.https_validate_certificates and HAVE_HTTPS_CONNECTION:
            boto.log.debug("wrapping ssl socket for proxied connection; "
                           "CA certificate file=%s",
                           self.ca_certificates_file)
            key_file = self.http_connection_kwargs.get('key_file', None)
            cert_file = self.http_connection_kwargs.get('cert_file', None)
            sslSock = ssl.wrap_socket(sock, keyfile=key_file,
                                      certfile=cert_file,
                                      cert_reqs=ssl.CERT_REQUIRED,
                                      ca_certs=self.ca_certificates_file)
            cert = sslSock.getpeercert()
            hostname = self.host.split(':', 0)[0]
            if not https_connection.ValidateCertificateHostname(cert, hostname):
                raise https_connection.InvalidCertificateException(
                        hostname, cert, 'hostname mismatch')
        else:
            # Fallback for old Python without ssl.wrap_socket
            if hasattr(httplib, 'ssl'):
                sslSock = httplib.ssl.SSLSocket(sock)
            else:
                sslSock = socket.ssl(sock, None, None)
                sslSock = httplib.FakeSocket(sock, sslSock)

        # This is a bit unclean
        h.sock = sslSock
        return h

    def prefix_proxy_to_path(self, path, host=None):
        path = self.protocol + '://' + (host or self.server_name()) + path
        return path

    def get_proxy_auth_header(self):
        auth = base64.encodestring(self.proxy_user + ':' + self.proxy_pass)
        return {'Proxy-Authorization': 'Basic %s' % auth}

    def _mexe(self, request, sender=None, override_num_retries=None,
              retry_handler=None):
        """
mexe - Multi-execute inside a loop, retrying multiple times to handle
transient Internet errors by simply trying again.
Also handles redirects.

This code was inspired by the S3Utils classes posted to the boto-users
Google group by Larry Bates. Thanks!

"""
        boto.log.debug('Method: %s' % request.method)
        boto.log.debug('Path: %s' % request.path)
        boto.log.debug('Data: %s' % request.body)
        boto.log.debug('Headers: %s' % request.headers)
        boto.log.debug('Host: %s' % request.host)
        response = None
        body = None
        e = None
        if override_num_retries is None:
            num_retries = config.getint('Boto', 'num_retries', self.num_retries)
        else:
            num_retries = override_num_retries
        i = 0
        connection = self.get_http_connection(request.host, self.is_secure)
        while i <= num_retries:
            # Use binary exponential backoff to desynchronize client requests
            next_sleep = random.random() * (2 ** i)
            try:
                # we now re-sign each request before it is retried
                boto.log.debug('Token: %s' % self.provider.security_token)
                request.authorize(connection=self)
                if callable(sender):
                    response = sender(connection, request.method, request.path,
                                      request.body, request.headers)
                else:
                    connection.request(request.method, request.path,
                                       request.body, request.headers)
                    response = connection.getresponse()
                location = response.getheader('location')
                # -- gross hack --
                # httplib gets confused with chunked responses to HEAD requests
                # so I have to fake it out
                if request.method == 'HEAD' and getattr(response,
                                                        'chunked', False):
                    response.chunked = 0
                if callable(retry_handler):
                    status = retry_handler(response, i, next_sleep)
                    if status:
                        msg, i, next_sleep = status
                        if msg:
                            boto.log.debug(msg)
                        time.sleep(next_sleep)
                        continue
                if response.status == 500 or response.status == 503:
                    msg = 'Received %d response. ' % response.status
                    msg += 'Retrying in %3.1f seconds' % next_sleep
                    boto.log.debug(msg)
                    body = response.read()
                elif response.status < 300 or response.status >= 400 or \
                        not location:
                    self.put_http_connection(request.host, self.is_secure,
                                             connection)
                    return response
                else:
                    scheme, request.host, request.path, \
                        params, query, fragment = urlparse.urlparse(location)
                    if query:
                        request.path += '?' + query
                    msg = 'Redirecting: %s' % scheme + '://'
                    msg += request.host + request.path
                    boto.log.debug(msg)
                    connection = self.get_http_connection(request.host,
                                                          scheme == 'https')
                    response = None
                    continue
            except self.http_exceptions, e:
                for unretryable in self.http_unretryable_exceptions:
                    if isinstance(e, unretryable):
                        boto.log.debug(
                            'encountered unretryable %s exception, re-raising' %
                            e.__class__.__name__)
                        raise e
                boto.log.debug('encountered %s exception, reconnecting' % \
                                  e.__class__.__name__)
                connection = self.new_http_connection(request.host,
                                                      self.is_secure)
            time.sleep(next_sleep)
            i += 1
        # If we made it here, it's because we have exhausted our retries
        # and stil haven't succeeded. So, if we have a response object,
        # use it to raise an exception.
        # Otherwise, raise the exception that must have already h#appened.
        if response:
            raise BotoServerError(response.status, response.reason, body)
        elif e:
            raise e
        else:
            msg = 'Please report this exception as a Boto Issue!'
            raise BotoClientError(msg)

    def build_base_http_request(self, method, path, auth_path,
                                params=None, headers=None, data='', host=None):
        path = self.get_path(path)
        if auth_path is not None:
            auth_path = self.get_path(auth_path)
        if params == None:
            params = {}
        else:
            params = params.copy()
        if headers == None:
            headers = {}
        else:
            headers = headers.copy()
        host = host or self.host
        if self.use_proxy:
            if not auth_path:
                auth_path = path
            path = self.prefix_proxy_to_path(path, host)
            if self.proxy_user and self.proxy_pass and not self.is_secure:
                # If is_secure, we don't have to set the proxy authentication
                # header here, we did that in the CONNECT to the proxy.
                headers.update(self.get_proxy_auth_header())
        return HTTPRequest(method, self.protocol, host, self.port,
                           path, auth_path, params, headers, data)

    def make_request(self, method, path, headers=None, data='', host=None,
                     auth_path=None, sender=None, override_num_retries=None,
                     params=None):
        """Makes a request to the server, with stock multiple-retry logic."""
        if params is None:
            params = {}
        http_request = self.build_base_http_request(method, path, auth_path,
                                                    params, headers, data, host)
        return self._mexe(http_request, sender, override_num_retries)

    def close(self):
        """(Optional) Close any open HTTP connections. This is non-destructive,
and making a new request will open a connection again."""

        boto.log.debug('closing all HTTP connections')
        self._connection = None # compat field


class AWSQueryConnection(AWSAuthConnection):

    APIVersion = ''
    ResponseError = BotoServerError

    def __init__(self, aws_access_key_id=None, aws_secret_access_key=None,
                 is_secure=True, port=None, proxy=None, proxy_port=None,
                 proxy_user=None, proxy_pass=None, host=None, debug=0,
                 https_connection_factory=None, path='/', security_token=None,
                 validate_certs=True):
        AWSAuthConnection.__init__(self, host, aws_access_key_id,
                                   aws_secret_access_key,
                                   is_secure, port, proxy,
                                   proxy_port, proxy_user, proxy_pass,
                                   debug, https_connection_factory, path,
                                   security_token=security_token,
                                   validate_certs=validate_certs)

    def _required_auth_capability(self):
        return []

    def get_utf8_value(self, value):
        return boto.utils.get_utf8_value(value)

    def make_request(self, action, params=None, path='/', verb='GET'):
        http_request = self.build_base_http_request(verb, path, None,
                                                    params, {}, '',
                                                    self.server_name())
        if action:
            http_request.params['Action'] = action
        if self.APIVersion:
            http_request.params['Version'] = self.APIVersion
        return self._mexe(http_request)

    def build_list_params(self, params, items, label):
        # Convert comma- or whitespace-delimited string to array
        if isinstance(items, basestring):
            items = [items]
        for i in range(1, len(items) + 1):
            params['%s.%d' % (label, i)] = items[i - 1]

    # generics

    def get_list(self, action, params, markers, path='/',
                 parent=None, verb='GET'):
        if not parent:
            parent = self
        response = self.make_request(action, params, path, verb)
        body = response.read()
        boto.log.debug(body)
        if not body:
            boto.log.error('Null body %s' % body)
            raise self.ResponseError(response.status, response.reason, body)
        elif response.status == 200:
            rs = ResultSet(markers)
            h = boto.handler.XmlHandler(rs, parent)
            xml.sax.parseString(body, h)
            return rs
        else:
            boto.log.error('%s %s' % (response.status, response.reason))
            boto.log.error('%s' % body)
            raise self.ResponseError(response.status, response.reason, body)

    def get_object(self, action, params, cls, path='/',
                   parent=None, verb='GET'):
        if not parent:
            parent = self
        response = self.make_request(action, params, path, verb)
        body = response.read()
        boto.log.debug(body)
        if not body:
            boto.log.error('Null body %s' % body)
            raise self.ResponseError(response.status, response.reason, body)
        elif response.status == 200:
            obj = cls(parent)
            h = boto.handler.XmlHandler(obj, parent)
            xml.sax.parseString(body, h)
            return obj
        else:
            boto.log.error('%s %s' % (response.status, response.reason))
            boto.log.error('%s' % body)
            raise self.ResponseError(response.status, response.reason, body)

    def get_status(self, action, params, path='/', parent=None, verb='GET'):
        if not parent:
            parent = self
        response = self.make_request(action, params, path, verb)
        body = response.read()
        boto.log.debug(body)
        if not body:
            boto.log.error('Null body %s' % body)
            raise self.ResponseError(response.status, response.reason, body)
        elif response.status == 200:
            rs = ResultSet()
            h = boto.handler.XmlHandler(rs, parent)
            xml.sax.parseString(body, h)
            return rs.status
        else:
            boto.log.error('%s %s' % (response.status, response.reason))
            boto.log.error('%s' % body)
            raise self.ResponseError(response.status, response.reason, body)
Something went wrong with that request. Please try again.