Source

riak-0.9.2 / client_lib / python / riak.py

   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
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
"""
Copyright 2010 Rusty Klophaus <rusty@basho.com>
Copyright 2010 Justin Sheehy <justin@basho.com>
Copyright 2009 Jay Baird <jay@mochimedia.com>

This file is provided to you 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.
"""

# Import libraries.
import sys, random, logging, base64, urllib, re
from cStringIO import StringIO

# Use pycurl as first choice, httplib as second choice.
try:
        import pycurl
        HAS_PYCURL = True
except ImportError:
        import httplib
        HAS_PYCURL = False

# Use json as first choice, simplejson as second choice.
try: 
        import json
except ImportError: 
        import simplejson as json


"""
This file is provided to you 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.    
"""

"""
The Riak API for Python allows you to connect to a Riak instance,
create, modify, and delete Riak objects, add and remove links from
Riak objects, run Javascript (and Erlang) based Map/Reduce
operations, and run Linkwalking operations.

See the unit_tests.php file for example usage.

@author Rusty Klophaus (@rklophaus) (rusty@basho.com)
@package RiakAPI
"""

class RiakClient:
        """
        The RiakClient object holds information necessary to connect to
        Riak. The Riak API uses HTTP, so there is no persistent
        connection, and the RiakClient object is extremely lightweight.
        """
        def __init__(self, host='127.0.0.1', port=8098, prefix='riak', mapred_prefix='mapred'):
                """
                Construct a new RiakClient object.
                @param string host - Hostname or IP address (default '127.0.0.1')
                @param int port - Port number (default 8098)
                @param string prefix - Interface prefix (default 'riak')
                @param string mapred_prefix - MapReduce prefix (default 'mapred')
                """
                self._host = host
                self._port = port
                self._prefix = prefix
                self._mapred_prefix = mapred_prefix
                self._client_id = 'php_' + base64.b64encode(str(random.randint(1, 1073741824)))
                self._r = 2
                self._w = 2
                self._dw = 2
                return None

        def get_r(self):
                """
                Get the R-value setting for this RiakClient. (default 2)
                @return integer
                """
                return self._r

        def set_r(self, r):
                """
                Set the R-value for this RiakClient. This value will be used
                for any calls to get(...) or get_binary(...) where where 1) no
                R-value is specified in the method call and 2) no R-value has
                been set in the RiakBucket.
                @param integer r - The R value.
                @return self
                """
                self._r = r
                return self

        def get_w(self):
                """
                Get the W-value setting for this RiakClient. (default 2)
                @return integer
                """
                return self._w

        def set_w(self, w):
                """
                Set the W-value for this RiakClient. See set_r(...) for a
                description of how these values are used.
                @param integer w - The W value.
                @return self
                """
                self._w = w
                return self

        def get_dw(self):
                """
                Get the DW-value for this ClientOBject. (default 2)
                @return integer
                """
                return self._dw
        
        def set_dw(self, dw):
                """
                Set the DW-value for this RiakClient. See set_r(...) for a
                description of how these values are used.
                @param integer dw - The DW value.
                @return self
                """
                self._dw = dw
                return self
        
        def get_client_id(self):
                """
                Get the client_id for this RiakClient.
                @return string
                """
                return self._client_id
        
        def set_client_id(self, client_id):
                """
                Set the client_id for this RiakClient. Should not be called
                unless you know what you are doing.
                @param string client_id - The new client_id.
                @return self
                """
                self._client_id = client_id
                return self

        def bucket(self, name):
                """
                Get the bucket by the specified name. Since buckets always exist,
                this will always return a RiakBucket.
                @return RiakBucket
                """
                return RiakBucket(self, name)
        
        def is_alive(self):
                """
                Check if the Riak server for this RiakClient is alive.
                @return boolean
                """
                response = RiakUtils.http_request('GET', self._host, self._port, '/ping')
                return(response != None) and (response[1] == 'OK')
        
        def add(self, *args):
                """
                Start assembling a Map/Reduce operation.
                @see RiakMapReduce.add()
                @return RiakMapReduce
                """
                mr = RiakMapReduce(self)
                return apply(mr.add, args)
        
        def link(self, args):
                """
                Start assembling a Map/Reduce operation.
                @see RiakMapReduce.link()
                """
                mr = RiakMapReduce(self)
                return apply(mr.link, args)
        
        def map(self, *args):
                """
                Start assembling a Map/Reduce operation.
                @see RiakMapReduce.map()
                """
                mr = RiakMapReduce(self)
                return apply(mr.map, args)
        
        def reduce(self, *args):
                """
                Start assembling a Map/Reduce operation.
                @see RiakMapReduce.reduce()
                """
                mr = RiakMapReduce(self)
                return apply(mr.reduce, args)
        
class RiakMapReduce:
        """
        The RiakMapReduce object allows you to build up and run a
        map/reduce operation on Riak.
        @package RiakMapReduce
        """

        def __init__(self, client):
                """
                Construct a Map/Reduce object.
                @param RiakClient client - A RiakClient object.
                @return RiakMapReduce
                """
                self._client = client
                self._phases = []
                self._inputs = []
                self._input_mode = None
        
        def add(self, arg1, arg2=None, arg3=None):
                """
                Add inputs to a map/reduce operation. This method takes three
                different forms, depending on the provided inputs. You can
                specify either a RiakObject, a string bucket name, or a bucket,
                key, and additional arg.
                @param mixed arg1 - RiakObject or Bucket
                @param mixed arg2 - Key or blank
                @param mixed arg3 - Arg or blank
                @return RiakMapReduce
                """
                if (arg2 == None) and (arg3 == None):
                        if isinstance(arg1, RiakObject):
                                return self.add_object(arg1)
                        else:
                                return self.add_bucket(arg1)
                else:
                        return self.add_bucket_key_data(arg1, arg2, arg3)
                
        def add_object(self, obj):
                return self.add_bucket_key_data(obj._bucket._name, obj._key, None)
                
        def add_bucket_key_data(self, bucket, key, data) :
                if self._input_mode == 'bucket':
                        raise Exception('Already added a bucket, can\'t add an object.')
                else:
                        self._inputs.append([bucket, key, data])
                        return self

        def add_bucket(self, bucket) :
                self._input_mode = 'bucket'
                self._inputs = bucket
                return self

        def link(self, bucket='_', tag='_', keep=False):
                """
                Add a link phase to the map/reduce operation.
                @param string bucket - Bucket name (default '_', which means all
                buckets)
                @param string tag - Tag (default '_', which means all buckets)
                @param boolean keep - Flag whether to keep results from this
                stage in the map/reduce. (default False, unless this is the last
                step in the phase)
                @return self
                """
                self._phases.append(RiakLinkPhase(bucket, tag, keep))
                return self
        
        def map(self, function, options=[]):
                """
                Add a map phase to the map/reduce operation.
                @param mixed function - Either a named Javascript function (ie:
                'Riak.mapValues'), or an anonymous javascript function (ie:
                'function(...)  ... ' or an array ['erlang_module',
                'function'].
                @param array() options - An optional associative array
                containing 'language', 'keep' flag, and/or 'arg'.
                @return self
                """
                if isinstance(function, list):
                        language = 'erlang'
                else: 
                        language='javascript'

                mr = RiakMapReducePhase('map',
                                        function,
                                        RiakUtils.get_value('language', options, language),
                                        RiakUtils.get_value('keep', options, False),
                                        RiakUtils.get_value('arg', options, None))
                self._phases.append(mr)
                return self

        def reduce(self, function, options=[]):
                """
                Add a reduce phase to the map/reduce operation.
                @param mixed function - Either a named Javascript function (ie.
                'Riak.mapValues'), or an anonymous javascript function(ie:
                'function(...) { ... }' or an array ['erlang_module', 'function'].
                @param array() options - An optional associative array
                containing 'language', 'keep' flag, and/or 'arg'.
                @return self
                """

                if isinstance(function, list):
                        language = 'erlang'
                else: 
                        language='javascript'

                mr = RiakMapReducePhase('reduce',
                                        function,
                                        RiakUtils.get_value('language', options, language),
                                        RiakUtils.get_value('keep', options, False),
                                        RiakUtils.get_value('arg', options, None))
                self._phases.append(mr)
                return self
                        
        def run(self, timeout=None):
                """
                Run the map/reduce operation. Returns an array of results, or an
                array of RiakLink objects if the last phase is a link phase.
                @param integer timeout - Timeout in seconds.
                @return array()
                """
                # Convert all phases to associative arrays. Also,
                # if none of the phases are accumulating, then set the last one to
                # accumulate.
                num_phases = len(self._phases)
                keep_flag = False
                query = []
                for i in range(num_phases):
                        phase = self._phases[i]
                        if (i == (num_phases - 1)) and (not keep_flag):
                                phase._keep = True
                        if phase._keep: keep_flag = True
                        query.append(phase.to_array())

                # Construct the job, optionally set the timeout...
                job = {'inputs':self._inputs, 'query':query}
                if timeout != None:
                        job['timeout'] = timeout

                content = json.dumps(job)

                # Do the request...
                host = self._client._host
                port = self._client._port
                url = "/" + self._client._mapred_prefix
                response = RiakUtils.http_request('POST', host, port, url, {}, content)
                result = json.loads(response[1])
                
                # If the last phase is NOT a link phase, then return the result.
                lastIsLink = isinstance(self._phases[-1], RiakLinkPhase)
                if not lastIsLink:
                        return result

                # Otherwise, if the last phase IS a link phase, then convert the
                # results to RiakLink objects.
                a = []
                for r in result:
                        link = RiakLink(r[0], r[1], r[2])
                        link._client = self._client
                        a.append(link)

                return a

class RiakMapReducePhase:
        """
        The RiakMapReducePhase holds information about a Map phase or
        Reduce phase in a RiakMapReduce operation.
        """

        def __init__(self, type, function, language, keep, arg):
                """
                Construct a RiakMapReducePhase object.
                @param string type - 'map'placeholder149'reduce'
                @param mixed function - string or array():
                @param string language - 'javascript'placeholder149'erlang'
                @param boolean keep - True to return the output of this phase in
                the results.
                @param mixed arg - Additional value to pass into the map or
                reduce function.
                """
                self._type = type
                self._language = language
                self._function = function
                self._keep = keep
                self._arg = arg
                return None

        def to_array(self):
                """
                Convert the RiakMapReducePhase to an associative array. Used
                internally.
                """
                stepdef = {'keep':self._keep,
                           'language':self._language,
                           'arg':self._arg}
                        
                if (self._language == 'javascript') and isinstance(self._function, list):
                        stepdef['bucket'] = self._function[0]
                        stepdef['key'] = self._function[1]
                elif (self._language == 'javascript') and isinstance(self._function, str):
                        if ("{" in self._function):
                                stepdef['source'] = self._function
                        else:
                                stepdef['name'] = self._function

                elif (self._language == 'erlang' and isinstance(self._function, list)):
                        stepdef['module'] = self._function[0]
                        stepdef['function'] = self._function[1]

                return {self._type : stepdef}

class RiakLinkPhase :
        """
        The RiakLinkPhase object holds information about a Link phase in a
        map/reduce operation.
        @package RiakLinkPhase
        """

        def __init__(self, bucket, tag, keep):
                """
                Construct a RiakLinkPhase object.
                @param string bucket - The bucket name.
                @param string tag - The tag.
                @param boolean keep - True to return results of this phase.
                """
                self._bucket = bucket
                self._tag = tag
                self._keep = keep
                return None

        def to_array(self):
                """
                Convert the RiakLinkPhase to an associative array. Used
                internally.
                """
                stepdef = {'bucket':self._bucket,
                           'tag':self._tag,
                           'keep':self._keep}
                return {'link':stepdef}

class RiakLink :
        """
        The RiakLink object represents a link from one Riak object to
        another.
        @package RiakLink
        """

        def __init__(self, bucket, key, tag=None):
                """
                Construct a RiakLink object.
                @param string bucket - The bucket name.
                @param string key - The key.
                @param string tag - The tag.
                """
                self._bucket = bucket
                self._key = key
                self._tag = tag
                self._client = None
                return None

        def get(self, r=None):
                """
                Retrieve the RiakObject to which this link points.
                @param integer r - The R-value to use.
                @return RiakObject
                """
                return self._client.bucket(self._bucket).get(self._key, r)

        def get_binary(self, r=None):
                """
                Retrieve the RiakObject to which this link points, as a binary.
                @param integer r - The R-value to use.
                @return RiakObject
                """
                return self._client.bucket(self._bucket).get_binary(self._key, r)

        def get_bucket(self):
                """
                Get the bucket name of this link.
                @return string
                """
                return self._bucket

        def set_bucket(self, name):
                """
                Set the bucket name of this link.
                @param string name - The bucket name.
                @return self
                """
                self._bucket = bucket
                return self

        def get_key(self):
                """
                Get the key of this link.
                @return string
                """
                return self._key
        
        def set_key(self, key):
                """
                Set the key of this link.
                @param string key - The key.
                @return self
                """
                self._key = key
                return self

        def get_tag(self):
                """
                Get the tag of this link.
                @return string
                """
                if (self._tag == None):
                        return self._bucket
                else:
                        return self._tag

        def set_tag(self, tag):
                """
                Set the tag of this link.
                @param string tag - The tag.
                @return self
                """
                self._tag = tag
                return self

        def to_link_header(self, client):
                """
                Convert this RiakLink object to a link header string. Used internally.
                """
                link = ''
                link += '</'
                link += client._prefix + '/'
                link += urllib.quote_plus(self._bucket) + '/'
                link += urllib.quote_plus(self._key) + '>; riaktag="'
                link += urllib.quote_plus(self.get_tag()) + '"'
                return link

        def isEqual(self, link):
                """
                Return True if the links are equal.
                @param RiakLink link - A RiakLink object.
                @return boolean
                """
                is_equal = (self._bucket == link._bucket) and (self._key == link._key) and (self.get_tag() == link.get_tag())
                return is_equal

class RiakBucket :
        """
        The RiakBucket object allows you to access and change information
        about a Riak bucket, and provides methods to create or retrieve
        objects within the bucket.
        @package RiakBucket
        """

        def __init__(self, client, name):
                self._client = client
                self._name = name
                self._r = None
                self._w = None
                self._dw = None
                return None

        def get_name(self):
                """
                Get the bucket name.
                """
                return self._name

        def get_r(self, r=None):
                """
                Get the R-value for this bucket, if it is set, otherwise return
                the R-value for the client.
                @return integer
                """
                if (r != None):
                        return r
                if (self._r != None):
                        return self._r
                return self._client.get_r()

        def set_r(self, r):
                """
                Set the R-value for this bucket. get(...) and get_binary(...)
                operations that do not specify an R-value will use this value.
                @param integer r - The new R-value.
                @return self
                """
                self._r = r
                return self
                                                         
        def get_w(self, w):
                """
                Get the W-value for this bucket, if it is set, otherwise return
                the W-value for the client.
                @return integer
                """
                if (w != None):
                        return w
                if (self._w != None):
                        return self._w
                return self._client.get_w()
        
        def set_w(self, w):
                """
                Set the W-value for this bucket. See set_r(...) for more information.
                @param integer w - The new W-value.
                @return self
                """
                self._w = w
                return self

        def get_dw(self, dw):
                """
                Get the DW-value for this bucket, if it is set, otherwise return
                the DW-value for the client.
                @return integer
                """
                if (dw != None):
                        return dw
                if (self._dw != None):
                        return self._dw
                return self._client.get_dw()
                                                         
        def set_dw(self, dw):
                """
                Set the DW-value for this bucket. See set_r(...) for more information.
                @param integer dw - The new DW-value
                @return self
                """
                self._dw = dw
                return self
                                                         
        def new(self, key, data=None):
                """
                Create a new Riak object that will be stored as JSON.
                @param string key - Name of the key.
                @param object data - The data to store. (default None)
                @return RiakObject
                """
                obj = RiakObject(self._client, self, key)
                obj.set_data(data)
                obj.set_content_type('text/json')
                obj._jsonize = True
                return obj
        
        def new_binary(self, key, data, content_type='text/json'):
                """
                Create a new Riak object that will be stored as plain text/binary.
                @param string key - Name of the key.
                @param object data - The data to store.
                @param string content_type - The content type of the object. (default 'text/json')
                @return RiakObject
                """
                obj = RiakObject(self._client, self, key)
                obj.set_data(data)
                obj.set_content_type('text/json')
                obj._jsonize = False
                return obj

        def get(self, key, r=None):
                """
                Retrieve a JSON-encoded object from Riak.
                @param string key - Name of the key.
                @param int r - R-Value of the request (defaults to bucket's R)
                @return RiakObject
                """
                obj = RiakObject(self._client, self, key)
                obj._jsonize = True
                r = self.get_r(r)
                return obj.reload(r)

        def get_binary(self, key, r=None):
                """
                Retrieve a binary/string object from Riak.
                @param string key - Name of the key.
                @param int r - R-Value of the request (defaults to bucket's R)
                @return RiakObject
                """
                obj = RiakObject(self._client, self, key)
                obj._jsonize = False
                r = self.get_r(r)
                return obj.reload(r)

        def set_n_val(self, nval):
                """
                Set the N-value for this bucket, which is the number of replicas
                that will be written of each object in the bucket. Set this once
                before you write any data to the bucket, and never change it
                again, otherwise unpredictable things could happen. This should
                only be used if you know what you are doing.
                @param integer nval - The new N-Val.
                """
                return self.set_property('n_val', nval)

        def get_n_val(self):
                """
                Retrieve the N-value for this bucket.
                @return integer                                                         
                """
                return self.get_property('n_val')

        def set_allow_multiples(self, bool):
                """
                If set to True, then writes with conflicting data will be stored
                and returned to the client. This situation can be detected by
                calling has_siblings() and get_siblings(). This should only be used
                if you know what you are doing.
                @param boolean bool - True to store and return conflicting writes.                                                         
                """
                return self.set_property('allow_mult', bool)

        def get_allow_multiples(self):
                """
                Retrieve the 'allow multiples' setting.
                @return Boolean
                """
                return self.get_property('allow_mult') == True

        def set_property(self, key, value):
                """
                Set a bucket property. This should only be used if you know what
                you are doing.
                @param string key - Property to set.
                @param mixed value - Property value.                                                         
                """
                return self.set_properties({key : value})

        def get_property(self, key):
                """
                Retrieve a bucket property.
                @param string key - The property to retrieve.
                @return mixed
                """
                props = self.get_properties()
                if (key in props.keys()):
                        return props[key]
                else:
                        return None

        def set_properties(self, props):
                """
                Set multiple bucket properties in one call. This should only be
                used if you know what you are doing.
                @param array props - An associative array of key:value.        
                """

                #Construct the URL, Headers, and Content...
                host, port, url = RiakUtils.build_rest_path(self._client, self)
                headers = {'Content-Type' : 'application/json'}
                content = json.dumps({'props' : props})
	
                #Run the request...
                response = RiakUtils.http_request('PUT', host, port, url, headers, content)

                # Handle the response...
                if (response == None):
                        raise Exception('Error setting bucket properties.')
        
                # Check the response value...
                status = response[0]['http_code']
                if (status != 204):
                        raise Exception('Error setting bucket properties.')

        def get_properties(self):
                """
                Retrieve an associative array of all bucket properties.
                @return Array		
                """
                
                # Run the request...
                params = {'props' : 'True', 'keys' : 'False'}
                host, port, url = RiakUtils.build_rest_path(self._client, self, None, None, params)
                response = RiakUtils.http_request('GET', host, port, url)
                
                # Use a RiakObject to interpret the response, we are just interested in the value.
                obj = RiakObject(self._client, self, None)
                obj.populate(response, [200])
                if (not obj.exists()):
                        raise Exception('Error getting bucket properties.')

                props = obj.get_data()
                props = props['props']
                return props

class RiakObject :
        """
        The RiakObject holds meta information about a Riak object, plus the
        object's data.
        @package RiakObject	
        """

        def __init__(self, client, bucket, key=None):
                """
                Construct a new RiakObject.
                @param RiakClient client - A RiakClient object.
                @param RiakBucket bucket - A RiakBucket object.
                @param string key - An optional key. If not specified, then key
                is generated by server when store(...) is called.		
                """
                self._client = client
                self._bucket = bucket
                self._key = key
                self._jsonize = True
                self._headers = {}
                self._links = []
                self._siblings = []
                self._exists = False
                return None

        def get_bucket(self):
                """
                Get the bucket of this object.
                @return RiakBucket
                """
                return self._bucket;

        def get_key(self):
                """
                Get the key of this object.
                @return string
                """
                return self._key


        def get_data(self):
                """
                Get the data stored in this object. Will return a associative
                array, unless the object was constructed with new_binary(...) or
                get_binary(...), in which case this will return a string.
                @return array or string		
                """
                return self._data
        
        def set_data(self, data):
                """
                Set the data stored in this object. This data will be
                JSON encoded unless the object was constructed with
                new_binary(...) or get_binary(...).
                @param mixed data - The data to store.
                @return data		
                """
                self._data = data
                return self
                
        def status(self):
                """
                Get the HTTP status from the last operation on this object.
                @return integer
                """
                return self._headers['http_code']
        
        def exists(self):
                """
                Return True if the object exists, False otherwise. Allows you to
                detect a get(...) or get_binary(...) operation where the object is missing.
                @return boolean
                """
                return self._exists
        
        def get_content_type(self):
                """
                Get the content type of this object. This is either text/json, or
                the provided content type if the object was created via new_binary(...).
                @return string
                """
                return self._headers['content-type']
        
        def set_content_type(self, content_type):
                """
                Set the content type of this object.
                @param string content_type - The new content type.
                @return self		
                """
                self._headers['content-type'] = content_type
                return self
        
        def add_link(self, obj, tag=None):
                """
                Add a link to a RiakObject.
                @param mixed obj - Either a RiakObject or a RiakLink object.
                @param string tag - Optional link tag. (default is bucket name,
                ignored if obj is a RiakLink object.)
                @return RiakObject		
                """
                if isinstance(obj, RiakLink):
                        newlink = obj
                else:
                        newlink = RiakLink(obj._bucket._name, obj._key, tag)
                        
                self.remove_link(newlink)
                self._links.append(newlink)
                return self
                
        def remove_link(self, obj, tag=None):
                """
                Remove a link to a RiakObject.
                @param mixed obj - Either a RiakObject or a RiakLink object.
                @param string tag -
                @param mixed obj - Either a RiakObject or a RiakLink object.
                @param string tag - Optional link tag. (default is bucket name,
                ignored if obj is a RiakLink object.)
                @return self		
                """
                if isinstance(obj, RiakLink):
                        oldlink = obj
                else:
                        oldlink = RiakLink(obj._bucket._name, obj._key, tag)
                        
                a = []
                for link in self._links:
                        if not link.isEqual(oldlink):
                                a.append(link)

                self._links = a
                return self

        def get_links(self):
                """
                Return an array of RiakLink objects.
                @return array()		
                """
                # Set the clients before returning...
                for link in self._links:
                        link._client = self._client
                return self._links
                        
        def store(self, w=None, dw=None):
                """
                Store the object in Riak. When this operation completes, the
                object could contain new metadata and possibly new data if Riak
                contains a newer version of the object according to the object's
                vector clock.
                @param integer w - W-value, wait for this many partitions to respond
                before returning to client.
                @param integer dw - DW-value, wait for this many partitions to
                confirm the write before returning to client.
                @return self		
                """
                # Use defaults if not specified...
                w = self._bucket.get_w(w)
                dw = self._bucket.get_dw(dw)
                
                # Construct the URL...
                params = {'returnbody' : 'true', 'w' : w, 'dw' : dw}
                host, port, url = RiakUtils.build_rest_path(self._client, self._bucket, self._key, None, params)
                
                # Construct the headers...
                headers = {'Accept' : 'text/plain, */*; q=0.5',
                           'Content-Type' : self.get_content_type(),
                           'X-Riak-ClientId' : self._client.get_client_id()}
                
                # Add the vclock if it exists...
                if (self.vclock() != None):
                        headers['X-Riak-Vclock'] = self.vclock()
                        
                # Add the Links...
                headers['Link'] = ''
                for link in self._links:
                        if headers['Link'] != '': headers['Link'] += ', '
                        headers['Link'] += link.to_link_header(self._client)
                        
                if (self._jsonize):
                        content = json.dumps(self.get_data())
                else:
                        content = self.get_data()
                
                # Run the operation.
                response = RiakUtils.http_request('PUT', host, port, url, headers, content)
                self.populate(response, [200, 300])
                return self

        def reload(self, r=None):
                """
                Reload the object from Riak. When this operation completes, the
                object could contain new metadata and a new value, if the object
                was updated in Riak since it was last retrieved.
                @param integer r - R-Value, wait for this many partitions to respond
                before returning to client.
                @return self		
                """
                # Do the request...
                r = self._bucket.get_r(r)
                params = {'r' : r}
                host, port, url = RiakUtils.build_rest_path(self._client, self._bucket, self._key, None, params)
                response = RiakUtils.http_request('GET', host, port, url)
                self.populate(response, [200, 300, 404])
                                
                # If there are siblings, load the data for the first one by default...
                if (self.has_siblings()):
                        obj = self.get_sibling(0)
                        self.set_data(obj.get_data())
                        
                return self

        def delete(self, dw=None):
                """
                Delete this object from Riak.
                @param integer dw - DW-value. Wait until this many partitions have
                deleted the object before responding.
                @return self		
                """
                # Use defaults if not specified...
                dw = self._bucket.get_dw(dw)
                
                # Construct the URL...
                params = {'dw' : dw}
                host, port, url = RiakUtils.build_rest_path(self._client, self._bucket, self._key, None, params)
                
                # Run the operation...
                response = RiakUtils.http_request('DELETE', host, port, url)
                self.populate(response, [204, 404])
                return self
                        
        def clear(self) :
                """
                Reset this object.
                @return self		
                """
                self._headers = []
                self._links = []
                self._data = None
                self._exists = False
                self._siblings = []
                return self
        
        def vclock(self) :
                """
                Get the vclock of this object.
                @return string		
                """
                if ('x-riak-vclock' in self._headers.keys()):
                        return self._headers['x-riak-vclock']
                else:
                        return None

        def populate(self, response, expected_statuses):
                """
                Given the output of RiakUtils.http_request and a list of
                statuses, populate the object. Only for use by the Riak client
                library.
                @return self		
                """
                self.clear()
                                
                # If no response given, then return.
                if (response == None):
                        return self
                
                # Update the object...
                self._headers = response[0]
                self._data = response[1]
                status = self.status()
                                
                # Check if the server is down(status==0)
                if (status == 0):
                        m = 'Could not contact Riak Server: http://' + self._client._host + ':' + str(self._client._port) + '!'
                        raise Exception(m)

                # Verify that we got one of the expected statuses. Otherwise, raise an exception.
                if (not status in expected_statuses):
                        m = 'Expected status ' + str(expected_statuses) + ', received ' + str(status)
                        raise Exception(m)

                # If 404(Not Found), then clear the object.
                if (status == 404):
                        self.clear()
                        return self
                        
                # If we are here, then the object exists...
                self._exists = True
	
                # Parse the link header...
                if ('link' in self._headers.keys()):
                        self.populate_links(self._headers['link'])

                # If 300(Siblings), then load the first sibling, and
                # store the rest.
                if (status == 300):
                        siblings = self._data.strip().split('\n')
                        siblings.pop(0)

                        # Get rid of 'Siblings:' string.
                        self._siblings = siblings
                        self._exists = True
                        return self

                # Possibly json_decode...
                if (status == 200 and self._jsonize):
                        self._data = json.loads(self._data)
        
                return self

        def populate_links(self, linkHeaders) :
                """
                Private.
                @return self		
                """
                for linkHeader in linkHeaders.strip().split(','):
                        linkHeader = linkHeader.strip()
                        matches = re.match("\<\/([^\/]+)\/([^\/]+)\/([^\/]+)\>; ?riaktag=\"([^\']+)\"", linkHeader)
                        if (matches != None):
                                link = RiakLink(matches.group(2), matches.group(3), matches.group(4))
                                self._links.append(link)
                return self

        def has_siblings(self):
                """
                Return True if this object has siblings.
                @return boolean
                """
                return(self.get_sibling_count() > 0)
        
        def get_sibling_count(self):
                """
                Get the number of siblings that this object contains.
                @return integer		
                """
                return len(self._siblings)
        
        def get_sibling(self, i, r=None):
                """
                Retrieve a sibling by sibling number.
                @param  integer i - Sibling number.
                @param  integer r - R-Value. Wait until this many partitions
                have responded before returning to client.
                @return RiakObject.		
                """
                # Use defaults if not specified.
                r = self._bucket.get_r(r)
                
                # Run the request...
                vtag = self._siblings[i]
                params = {'r' : r, 'vtag' : vtag}
                host, port, url = RiakUtils.build_rest_path(self._client, self._bucket, self._key, None, params)
                response = RiakUtils.http_request('GET', host, port, url)
                
                # Respond with a new object...
                obj = RiakObject(self._client, self._bucket, self._key)
                obj._jsonize = self._jsonize
                obj.populate(response, [200])
                return obj

        def get_siblings(self, r=None):
                """
                Retrieve an array of siblings.
                @param integer r - R-Value. Wait until this many partitions have
                responded before returning to client.
                @return array of RiakObject		
                """
                a = []
                for i in range(self.get_sibling_count()):
                        a.append(self.get_sibling(i, r))
                return a
                
        def add(self, *args):
                """
                Start assembling a Map/Reduce operation.
                @see RiakMapReduce.add()
                @return RiakMapReduce		
                """
                mr = RiakMapReduce(self._client)
                mr.add(self._bucket._name, self._key)
                return apply(mr.add, args)
        
        def link(self, *args):
                """
                Start assembling a Map/Reduce operation.
                @see RiakMapReduce.link()
                @return RiakMapReduce		
                """
                mr = RiakMapReduce(self._client)
                mr.add(self._bucket._name, self._key)
                return apply(mr.link, args)
        
        def map(self, *args):
                """
                Start assembling a Map/Reduce operation.
                @see RiakMapReduce.map()
                @return RiakMapReduce
                """
                mr = RiakMapReduce(self._client)
                mr.add(self._bucket._name, self._key)
                return apply(mr.map, args)
        
        def reduce(self, params):
                """
                Start assembling a Map/Reduce operation.
                @see RiakMapReduce.reduce()
                @return RiakMapReduce
                """
                mr = RiakMapReduce(self._client)
                mr.add(self._bucket._name, self._key)
                return apply(mr.reduce, args)
        
class RiakUtils :
        """
        Utility functions used by Riak library.
        @package RiakUtils	
        """
        @classmethod
        def get_value(self, key, array, defaultValue) :
                if (key in array):
                        return array[key]
                else:
                        return defaultValue
		
        @classmethod
        def build_rest_path(self, client, bucket, key=None, spec=None, params=None) :
                """
                Given a RiakClient, RiakBucket, Key, LinkSpec, and Params,
                construct and return a URL.		
                """
                # Build 'http://hostname:port/prefix/bucket'
                path = ''
		path += '/' + client._prefix
		path += '/' + urllib.quote_plus(bucket._name)

                # Add '.../key'
                if (key != None):
                        path += '/' + urllib.quote_plus(key)
                        
                # Add query parameters.
                if (params != None):
                        s = ''
                        for key in params.keys():
                                if (s != ''): s += '&'
                                s += urllib.quote_plus(key) + '=' + urllib.quote_plus(str(params[key]))
                        path += '?' + s

                # Return.
                return client._host, client._port, path

        @classmethod
        def http_request(self, method, host, port, url, headers = {}, obj = '') :
                """
                Given a Method, URL, Headers, and Body, perform and HTTP request,
                and return an array of arity 2 containing an associative array of
                response headers and the response body.
                """
                if HAS_PYCURL:
                        return self.pycurl_request(method, host, port, url, headers, obj)
                else:
                        return self.httplib_request(method, host, port, url, headers, obj)


        @classmethod
        def httplib_request(self, method, host, port, uri, headers={}, body=''):
                # Run the request...
                client = None
                response = None
                try:
                        client = httplib.HTTPConnection(host, port)
                        client.request(method, uri, body, headers)
                        response = client.getresponse()

                        # Get the response headers...
                        response_headers = {}
                        response_headers['http_code'] = response.status
                        for (key, value) in response.getheaders():
                                response_headers[key.lower()] = value

                        # Get the body...
                        response_body = response.read()
                        response.close()

                        return response_headers, response_body
                except:
                        if client != None: client.close()
                        if response != None: response.close()
                        raise

        
        @classmethod
        def pycurl_request(self, method, host, port, uri, headers={}, body=''):
                url = "http://" + host + ":" + str(port) + uri
                # Set up Curl...
                client = pycurl.Curl()
                client.setopt(pycurl.URL, url)                
                client.setopt(pycurl.HTTPHEADER, self.build_headers(headers))
                if method == 'GET':
                        client.setopt(pycurl.HTTPGET, 1)
                elif method == 'POST':
                        client.setopt(pycurl.POST, 1)                        
                        client.setopt(pycurl.POSTFIELDS, body)
                elif method == 'PUT':
                        client.setopt(pycurl.CUSTOMREQUEST, method)        
                        client.setopt(pycurl.POSTFIELDS, body)
                elif method == 'DELETE':
                        client.setopt(pycurl.CUSTOMREQUEST, method)

                # Capture the response headers...
                response_headers_io = StringIO()
                client.setopt(pycurl.HEADERFUNCTION, response_headers_io.write)
                
                # Capture the response body...
                response_body_io = StringIO()
                client.setopt(pycurl.WRITEFUNCTION, response_body_io.write)

                try:
                        # Run the request.
                        client.perform()
                        http_code = client.getinfo(pycurl.HTTP_CODE)
                        client.close()
                        
                        # Get the headers...
                        response_headers = self.parse_http_headers(response_headers_io.getvalue())
                        response_headers['http_code'] = http_code
                        
                        # Get the body...
                        response_body = response_body_io.getvalue()

                        return response_headers, response_body
                except:
                        if (client != None) : client.close()
                        raise

        @classmethod
        def build_headers(self, headers):
                headers1 = []
                for key in headers.keys():
                        headers1.append('%s: %s' % (key, headers[key]))
                return headers1

        @classmethod
        def parse_http_headers(self, headers) :
                """
                Parse an HTTP Header string into an asssociative array of
                response headers.		
                """
                retVal = {}
                fields = headers.split("\n")
                for field in fields:
                        matches = re.match("([^:]+):(.+)", field)
                        if (matches == None): continue
                        key = matches.group(1).lower()
                        value = matches.group(2).strip()
                        if (key in retVal.keys()):
                                if  isinstance(retVal[key], list):
                                        retVal[key].append(value)
                                else:
                                        retVal[key] = [retVal[key]].append(value)
                        else:
                                retVal[key] = value
                return retVal