This file is indexed.

/usr/bin/ovs-dpctl-top is in openvswitch-switch 2.9.0-0ubuntu1.

This file is owned by root:root, with mode 0o755.

The actual contents of the file can be viewed below.

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
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
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
#! /usr/bin/python
#
# Copyright (c) 2013 Nicira, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
#
# The approximate_size code was copied from
# http://getpython3.com/diveintopython3/your-first-python-program.html#divingin
# which is licensed under # "Dive Into Python 3," Copyright 2011 Mark Pilgrim,
# used under a Creative Commons Attribution-Share-Alike license:
# http://creativecommons.org/licenses/by-sa/3.0/
#
#

"""Top like behavior for ovs-dpctl dump-flows output.

This program summarizes ovs-dpctl flow content by aggregating the number
of packets, total bytes and occurrence of the following fields:

  - Datapath in_port

  - Ethernet type

  - Source and destination MAC addresses

  - IP protocol

  - Source and destination IPv4 addresses

  - Source and destination IPv6 addresses

  - UDP and TCP destination port

  - Tunnel source and destination addresses


Output shows four values:
  - FIELDS: the flow fields for example in_port(1).

  - PACKETS: the total number of packets containing the flow field.

  - BYTES: the total number of bytes containing the flow field. If units are
  not present then values are in bytes.

  - AVERAGE: the average packets size (BYTES/PACKET).

  - COUNT: the number of lines in the dump-flow output contain the flow field.

Top Behavior

While in top mode, the default behavior, the following single character
commands are supported:

  a - toggles top in accumulate and live mode. Accumulate mode is described
  below.

  s - toggles which column is used to sort content in decreasing order. A
  DESC title is placed over the column.

  _ - a space indicating to collect dump-flow content again

  h - halt output. Any character will restart sampling

  f - cycle through flow fields. The initial field is in_port

  q - q for quit.

Accumulate Mode

There are two supported modes: live and accumulate. The default is live.
The parameter --accumulate  or the 'a' character in top mode enables the
latter. In live mode, recent dump-flow content is presented.
Where as accumulate mode keeps track of the prior historical
information until the flow is reset not when the flow is purged. Reset
flows are determined when the packet count for a flow has decreased from
its previous sample. There is one caveat, eventually the system will
run out of memory if, after the accumulate-decay period any flows that
have not been refreshed are purged. The goal here is to free memory
of flows that are not active. Statistics are not decremented. Their purpose
is to reflect the overall history of the flow fields.


Debugging Errors

Parsing errors are counted and displayed in the status line at the beginning
of the output. Use the --verbose option with --script to see what output
 was not parsed, like this:
$ ovs-dpctl dump-flows | ovs-dpctl-top --script --verbose

Error messages will identify content that failed to parse.


Access Remote Hosts

The --host must follow the format user@hostname. This script simply calls
'ssh user@Hostname' without checking for login credentials therefore public
keys should be installed on the system identified by hostname, such as:

$ ssh-copy-id user@hostname

Consult ssh-copy-id man pages for more details.


Expected usage

$ ovs-dpctl-top

or to run as a script:
$ ovs-dpctl dump-flows > dump-flows.log
$ ovs-dpctl-top --script --flow-file dump-flows.log

"""

# pylint: disable-msg=C0103
# pylint: disable-msg=C0302
# pylint: disable-msg=R0902
# pylint: disable-msg=R0903
# pylint: disable-msg=R0904
# pylint: disable-msg=R0912
# pylint: disable-msg=R0913
# pylint: disable-msg=R0914

import sys
import os
try:
    ##
    # Arg parse is not installed on older Python distributions.
    # ovs ships with a version in the directory mentioned below.
    import argparse
except ImportError:
    sys.path.append(os.path.join("/usr/share/openvswitch", "python"))
    import argparse
import logging
import re
import unittest
import copy
import curses
import operator
import subprocess
import fcntl
import struct
import termios
import datetime
import threading
import time
import socket


##
# The following two definitions provide the necessary netaddr functionality.
# Python netaddr module is not part of the core installation. Packaging
# netaddr was involved and seems inappropriate given that only two
# methods where used.
def ipv4_to_network(ip_str):
    """ Calculate the network given a ipv4/mask value.
    If a mask is not present simply return ip_str.
    """
    pack_length = '!HH'
    try:
        (ip, mask) = ip_str.split("/")
    except ValueError:
        # just an ip address no mask.
        return ip_str

    ip_p = socket.inet_pton(socket.AF_INET, ip)
    ip_t = struct.unpack(pack_length, ip_p)
    mask_t = struct.unpack(pack_length, socket.inet_pton(socket.AF_INET, mask))
    network_n = [ii & jj for (ii, jj) in zip(ip_t, mask_t)]

    return socket.inet_ntop(socket.AF_INET,
                            struct.pack('!HH', network_n[0], network_n[1]))


def ipv6_to_network(ip_str):
    """ Calculate the network given a ipv6/mask value.
    If a mask is not present simply return ip_str.
    """
    pack_length = '!HHHHHHHH'
    try:
        (ip, mask) = ip_str.split("/")
    except ValueError:
        # just an ip address no mask.
        return ip_str

    ip_p = socket.inet_pton(socket.AF_INET6, ip)
    ip_t = struct.unpack(pack_length, ip_p)
    mask_t = struct.unpack(pack_length,
                           socket.inet_pton(socket.AF_INET6, mask))
    network_n = [ii & jj for (ii, jj) in zip(ip_t, mask_t)]

    return socket.inet_ntop(socket.AF_INET6,
                            struct.pack(pack_length,
                                        network_n[0], network_n[1],
                                        network_n[2], network_n[3],
                                        network_n[4], network_n[5],
                                        network_n[6], network_n[7]))


##
# columns displayed
##
class Columns:
    """ Holds column specific content.
    Titles needs to be less than 8 characters.
    """
    VALUE_WIDTH = 9
    FIELDS = "fields"
    PACKETS = "packets"
    COUNT = "count"
    BYTES = "bytes"
    AVERAGE = "average"

    def __init__(self):
        pass

    @staticmethod
    def assoc_list(obj):
        """ Return a associated list. """
        return [(Columns.FIELDS, repr(obj)),
                (Columns.PACKETS, obj.packets),
                (Columns.BYTES, obj.bytes),
                (Columns.COUNT, obj.count),
                (Columns.AVERAGE, obj.average),
                ]


def element_eth_get(field_type, element, stats_dict):
    """ Extract eth frame src and dst from a dump-flow element."""
    fmt = "%s(src=%s,dst=%s)"

    element = fmt % (field_type, element["src"], element["dst"])
    return SumData(field_type, element, stats_dict["packets"],
                   stats_dict["bytes"], element)


def element_ipv4_get(field_type, element, stats_dict):
    """ Extract src and dst from a dump-flow element."""
    fmt = "%s(src=%s,dst=%s)"
    element_show = fmt % (field_type, element["src"], element["dst"])

    element_key = fmt % (field_type, ipv4_to_network(element["src"]),
                         ipv4_to_network(element["dst"]))

    return SumData(field_type, element_show, stats_dict["packets"],
                       stats_dict["bytes"], element_key)


def element_tunnel_get(field_type, element, stats_dict):
    """ Extract src and dst from a tunnel."""
    return element_ipv4_get(field_type, element, stats_dict)


def element_ipv6_get(field_type, element, stats_dict):
    """ Extract src and dst from a dump-flow element."""

    fmt = "%s(src=%s,dst=%s)"
    element_show = fmt % (field_type, element["src"], element["dst"])

    element_key = fmt % (field_type, ipv6_to_network(element["src"]),
                         ipv6_to_network(element["dst"]))

    return SumData(field_type, element_show, stats_dict["packets"],
                       stats_dict["bytes"], element_key)


def element_dst_port_get(field_type, element, stats_dict):
    """ Extract src and dst from a dump-flow element."""
    element_key = "%s(dst=%s)" % (field_type, element["dst"])
    return SumData(field_type, element_key, stats_dict["packets"],
                   stats_dict["bytes"], element_key)


def element_passthrough_get(field_type, element, stats_dict):
    """ Extract src and dst from a dump-flow element."""
    element_key = "%s(%s)" % (field_type, element)
    return SumData(field_type, element_key,
                   stats_dict["packets"], stats_dict["bytes"], element_key)


# pylint: disable-msg=R0903
class OutputFormat:
    """ Holds field_type and function to extract element value. """
    def __init__(self, field_type, generator):
        self.field_type = field_type
        self.generator = generator

##
# The order below is important. The initial flow field depends on whether
# --script or top mode is used. In top mode, the expected behavior, in_port
# flow fields are shown first. A future feature will allow users to
# filter output by selecting a row. Filtering by in_port is a natural
# filtering starting point.
#
# In script mode, all fields are shown. The expectation is that users could
# filter output by piping through grep.
#
# In top mode, the default flow field is in_port. In --script mode,
# the default flow field is all.
#
# All is added to the end of the OUTPUT_FORMAT list.
##
OUTPUT_FORMAT = [
    OutputFormat("in_port", element_passthrough_get),
    OutputFormat("eth", element_eth_get),
    OutputFormat("eth_type", element_passthrough_get),
    OutputFormat("ipv4", element_ipv4_get),
    OutputFormat("ipv6", element_ipv6_get),
    OutputFormat("udp", element_dst_port_get),
    OutputFormat("tcp", element_dst_port_get),
    OutputFormat("tunnel", element_tunnel_get),
    ]
##


ELEMENT_KEY = {
    "udp": "udp.dst",
    "tcp": "tcp.dst"
    }


def top_input_get(args):
    """ Return subprocess stdout."""
    cmd = []
    if (args.host):
        cmd += ["ssh", args.host]
    cmd += ["ovs-dpctl", "dump-flows"]

    return subprocess.Popen(cmd, stderr=subprocess.STDOUT,
                            stdout=subprocess.PIPE).stdout


def args_get():
    """ read program parameters handle any necessary validation of input. """

    parser = argparse.ArgumentParser(
                          formatter_class=argparse.RawDescriptionHelpFormatter,
                          description=__doc__)
    ##
    # None is a special value indicating to read flows from stdin.
    # This handles the case
    #   ovs-dpctl dump-flows | ovs-dpctl-flows.py
    parser.add_argument("-v", "--version", version="2.9.0",
                        action="version", help="show version")
    parser.add_argument("-f", "--flow-file", dest="flowFiles", default=None,
                        action="append",
                        help="file containing flows from ovs-dpctl dump-flow")
    parser.add_argument("-V", "--verbose", dest="verbose",
                        default=logging.CRITICAL,
                        action="store_const", const=logging.DEBUG,
                        help="enable debug level verbosity")
    parser.add_argument("-s", "--script", dest="top", action="store_false",
                        help="Run from a script (no user interface)")
    parser.add_argument("--host", dest="host",
                        help="Specify a user@host for retrieving flows see"
                             "Accessing Remote Hosts for more information")

    parser.add_argument("-a", "--accumulate", dest="accumulate",
                        action="store_true", default=False,
                        help="Accumulate dump-flow content")
    parser.add_argument("--accumulate-decay", dest="accumulateDecay",
                        default=5.0 * 60, type=float,
                        help="Decay old accumulated flows. "
                        "The default is 5 minutes. "
                        "A value of 0 disables decay.")
    parser.add_argument("-d", "--delay", dest="delay", type=int,
                        default=1000,
                        help="Delay in milliseconds to collect dump-flow "
                             "content (sample rate).")

    args = parser.parse_args()

    logging.basicConfig(level=args.verbose)

    return args

###
# Code to parse a single line in dump-flow
###
# key(values)
FIELDS_CMPND = re.compile("([\w]+)\((.+)\)")
# key:value
FIELDS_CMPND_ELEMENT = re.compile("([\w:]+)=([/\.\w:]+)")
FIELDS_ELEMENT = re.compile("([\w]+):([-\.\w]+)")


def flow_line_iter(line):
    """ iterate over flow dump elements.
    return tuples of (true, element) or (false, remaining element)
    """
    # splits by , except for when in a (). Actions element was not
    # split properly but we don't need it.
    rc = []

    element = ""
    paren_count = 0

    for ch in line:
        if (ch == '('):
            paren_count += 1
        elif (ch == ')'):
            paren_count -= 1

        if (ch == ' '):
            # ignore white space.
            continue
        elif ((ch == ',') and (paren_count == 0)):
            rc.append(element)
            element = ""
        else:
            element += ch

    if (paren_count):
        raise ValueError(line)
    else:
        if (len(element) > 0):
            rc.append(element)
    return rc


def flow_line_compound_parse(compound):
    """ Parse compound element
    for example
    src=00:50:56:b4:4e:f8,dst=33:33:00:01:00:03
    which is in
    eth(src=00:50:56:b4:4e:f8,dst=33:33:00:01:00:03)
    """
    result = {}
    for element in flow_line_iter(compound):
        match = FIELDS_CMPND_ELEMENT.search(element)
        if (match):
            key = match.group(1)
            value = match.group(2)
            result[key] = value

        match = FIELDS_CMPND.search(element)
        if (match):
            key = match.group(1)
            value = match.group(2)
            result[key] = flow_line_compound_parse(value)
            continue

    if (len(result.keys()) == 0):
        return compound
    return result


def flow_line_split(line):
    """ Convert a flow dump line into ([fields], [stats], actions) tuple.
    Where fields and stats are lists.
    This function relies on a the following ovs-dpctl dump-flow
    output characteristics:
    1. The dumpe flow line consists of a list of frame fields, list of stats
       and action.
    2. list of frame fields, each stat and action field are delimited by ', '.
    3. That all other non stat field are not delimited by ', '.

    """

    results = re.split(', ', line)

    (field, stats, action) = (results[0], results[1:-1], results[-1])

    fields = flow_line_iter(field)
    return (fields, stats, action)


def elements_to_dict(elements):
    """ Convert line to a hierarchy of dictionaries. """
    result = {}
    for element in elements:
        match = FIELDS_CMPND.search(element)
        if (match):
            key = match.group(1)
            value = match.group(2)
            result[key] = flow_line_compound_parse(value)
            continue

        match = FIELDS_ELEMENT.search(element)
        if (match):
            key = match.group(1)
            value = match.group(2)
            result[key] = value
        else:
            raise ValueError("can't parse >%s<" % element)
    return result


# pylint: disable-msg=R0903
class SumData(object):
    """ Interface that all data going into SumDb must implement.
    Holds the flow field and its corresponding count, total packets,
    total bytes and calculates average.

    __repr__ is used as key into SumData singleton.
    __str__ is used as human readable output.
    """

    def __init__(self, field_type, field, packets, flow_bytes, key):
        # Count is the number of lines in the dump-flow log.
        self.field_type = field_type
        self.field = field
        self.count = 1
        self.packets = int(packets)
        self.bytes = int(flow_bytes)
        self.key = key

    def decrement(self, decr_packets, decr_bytes, decr_count):
        """ Decrement content to calculate delta from previous flow sample."""
        self.packets -= decr_packets
        self.bytes -= decr_bytes
        self.count -= decr_count

    def __iadd__(self, other):
        """ Add two objects. """

        if (self.key != other.key):
            raise ValueError("adding two unrelated types")

        self.count += other.count
        self.packets += other.packets
        self.bytes += other.bytes
        return self

    def __isub__(self, other):
        """ Decrement two objects. """

        if (self.key != other.key):
            raise ValueError("adding two unrelated types")

        self.count -= other.count
        self.packets -= other.packets
        self.bytes -= other.bytes
        return self

    def __getattr__(self, name):
        """ Handle average. """
        if (name == "average"):
            if (self.packets == 0):
                return float(0.0)
            else:
                return float(self.bytes) / float(self.packets)
        raise AttributeError(name)

    def __str__(self):
        """ Used for debugging. """
        return "%s %s %s %s" % (self.field, self.count,
                                   self.packets, self.bytes)

    def __repr__(self):
        """ Used as key in the FlowDB table. """
        return self.key


def flow_aggregate(fields_dict, stats_dict):
    """ Search for content in a line.
    Passed the flow port of the dump-flows plus the current stats consisting
    of packets, bytes, etc
    """
    result = []

    for output_format in OUTPUT_FORMAT:
        field = fields_dict.get(output_format.field_type, None)
        if (field):
            obj = output_format.generator(output_format.field_type,
                                          field, stats_dict)
            result.append(obj)

    return result


def flows_read(ihdl, flow_db):
    """ read flow content from ihdl and insert into flow_db. """

    done = False
    while (not done):
        line = ihdl.readline()
        if (len(line) == 0):
            # end of input
            break

        try:
            flow_db.flow_line_add(line)
        except ValueError, arg:
            logging.error(arg)

    return flow_db


def get_terminal_size():
    """
    return column width and height of the terminal
    """
    for fd_io in [0, 1, 2]:
        try:
            result = struct.unpack('hh',
                                   fcntl.ioctl(fd_io, termios.TIOCGWINSZ,
                                               '1234'))
        except IOError:
            result = None
            continue

    if (result is None or result == (0, 0)):
        # Maybe we can't get the width. In that case assume (25, 80)
        result = (25, 80)

    return result

##
# Content derived from:
# http://getpython3.com/diveintopython3/your-first-python-program.html#divingin
##
SUFFIXES = {1000: ['KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'],
            1024: ['KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB']}


def approximate_size(size, a_kilobyte_is_1024_bytes=True):
    """Convert a file size to human-readable form.

    Keyword arguments:
    size -- file size in bytes
    a_kilobyte_is_1024_bytes -- if True (default), use multiples of 1024
                                    if False, use multiples of 1000

    Returns: string

    """
    size = float(size)
    if size < 0:
        raise ValueError('number must be non-negative')

    if (a_kilobyte_is_1024_bytes):
        multiple = 1024
    else:
        multiple = 1000
    for suffix in SUFFIXES[multiple]:
        size /= multiple
        if size < multiple:
            return "%.1f %s" % (size, suffix)

    raise ValueError('number too large')


##
# End copied content
##
class ColMeta:
    """ Concepts about columns. """
    def __init__(self, sortable, width):
        self.sortable = sortable
        self.width = width


class RowMeta:
    """ How to render rows. """
    def __init__(self, label, fmt):
        self.label = label
        self.fmt = fmt


def fmt_packet(obj, width):
    """ Provide a string for packets that is appropriate for output."""
    return str(obj.packets).rjust(width)


def fmt_count(obj, width):
    """ Provide a string for average that is appropriate for output."""
    return str(obj.count).rjust(width)


def fmt_avg(obj, width):
    """ Provide a string for average that is appropriate for output."""
    return str(int(obj.average)).rjust(width)


def fmt_field(obj, width):
    """ truncate really long flow and insert ellipses to help make it
    clear.
    """

    ellipses = " ... "
    value = obj.field
    if (len(obj.field) > width):
        value = value[:(width - len(ellipses))] + ellipses
    return value.ljust(width)


def fmt_bytes(obj, width):
    """ Provide a string for average that is appropriate for output."""
    if (len(str(obj.bytes)) <= width):
        value = str(obj.bytes)
    else:
        value = approximate_size(obj.bytes)
    return value.rjust(width)


def title_center(value, width):
    """ Center a column title."""
    return value.upper().center(width)


def title_rjust(value, width):
    """ Right justify a column title. """
    return value.upper().rjust(width)


def column_picker(order, obj):
    """ return the column as specified by order. """
    if (order == 1):
        return obj.count
    elif (order == 2):
        return obj.packets
    elif (order == 3):
        return obj.bytes
    elif (order == 4):
        return obj.average
    else:
        raise ValueError("order outside of range %s" % order)


class Render:
    """ Renders flow data.

    The two FIELD_SELECT variables should be set to the actual field minus
    1. During construction, an internal method increments and initializes
    this object.
    """
    FLOW_FIELDS = [_field.field_type for _field in OUTPUT_FORMAT] + ["all"]

    FIELD_SELECT_SCRIPT = 7
    FIELD_SELECT_TOP = -1

    def __init__(self, console_width, field_select):
        """ Calculate column widths taking into account changes in format."""

        self._start_time = datetime.datetime.now()

        self._cols = [ColMeta(False, 0),
                      ColMeta(True, Columns.VALUE_WIDTH),
                      ColMeta(True, Columns.VALUE_WIDTH),
                      ColMeta(True, Columns.VALUE_WIDTH),
                      ColMeta(True, Columns.VALUE_WIDTH)]
        self._console_width = console_width
        self.console_width_set(console_width)

        # Order in this array dictate the order of the columns.
        # The 0 width for the first entry is a place holder. This is
        # dynamically calculated. The first column is special. We need a
        # way to indicate which field are presented.
        self._descs = [RowMeta("", title_rjust),
                       RowMeta("", title_rjust),
                       RowMeta("", title_rjust),
                       RowMeta("", title_rjust),
                       RowMeta("", title_rjust)]
        self._column_sort_select = 0
        self.column_select_event()

        self._titles = [
            RowMeta(Columns.FIELDS, title_center),
            RowMeta(Columns.COUNT, title_rjust),
            RowMeta(Columns.PACKETS, title_rjust),
            RowMeta(Columns.BYTES, title_rjust),
            RowMeta(Columns.AVERAGE, title_rjust)
        ]

        self._datas = [
            RowMeta(None, fmt_field),
            RowMeta(None, fmt_count),
            RowMeta(None, fmt_packet),
            RowMeta(None, fmt_bytes),
            RowMeta(None, fmt_avg)
            ]

        ##
        # _field_types hold which fields are displayed in the field
        # column, with the keyword all implying all fields.
        ##
        self._field_types = Render.FLOW_FIELDS

        ##
        # The default is to show all field types.
        ##
        self._field_type_select = field_select
        self.field_type_toggle()

    def _field_type_select_get(self):
        """ Return which field type to display. """
        return self._field_types[self._field_type_select]

    def field_type_toggle(self):
        """ toggle which field types to show. """
        self._field_type_select += 1
        if (self._field_type_select >= len(self._field_types)):
            self._field_type_select = 0
        value = Columns.FIELDS + " (%s)" % self._field_type_select_get()
        self._titles[0].label = value

    def column_select_event(self):
        """ Handles column select toggle. """

        self._descs[self._column_sort_select].label = ""
        for _ in range(len(self._cols)):
            self._column_sort_select += 1
            if (self._column_sort_select >= len(self._cols)):
                self._column_sort_select = 0

            # Now look for the next sortable column
            if (self._cols[self._column_sort_select].sortable):
                break
        self._descs[self._column_sort_select].label = "DESC"

    def console_width_set(self, console_width):
        """ Adjust the output given the new console_width. """
        self._console_width = console_width

        spaces = len(self._cols) - 1
        ##
        # Calculating column width can be tedious but important. The
        # flow field value can be long. The goal here is to dedicate
        # fixed column space for packets, bytes, average and counts. Give the
        # remaining space to the flow column. When numbers get large
        # transition output to output generated by approximate_size which
        # limits output to ###.# XiB in other words 9 characters.
        ##
        # At this point, we know the maximum length values. We may
        # truncate the flow column to get everything to fit.
        self._cols[0].width = 0
        values_max_length = sum([ii.width for ii in self._cols]) + spaces
        flow_max_length = console_width - values_max_length
        self._cols[0].width = flow_max_length

    def format(self, flow_db):
        """ shows flows based on --script parameter."""

        rc = []
        ##
        # Top output consists of
        # Title
        # Column title (2 rows)
        # data
        # statistics and status

        ##
        # Title
        ##
        rc.append("Flow Summary".center(self._console_width))

        stats = " Total: %(flow_total)s  errors: %(flow_errors)s " % \
                  flow_db.flow_stats_get()
        accumulate = flow_db.accumulate_get()
        if (accumulate):
            stats += "Accumulate: on "
        else:
            stats += "Accumulate: off "

        duration = datetime.datetime.now() - self._start_time
        stats += "Duration: %s " % str(duration)
        rc.append(stats.ljust(self._console_width))

        ##
        # 2 rows for columns.
        ##
        # Indicate which column is in descending order.
        rc.append(" ".join([ii.fmt(ii.label, col.width)
                            for (ii, col) in zip(self._descs, self._cols)]))

        rc.append(" ".join([ii.fmt(ii.label, col.width)
                         for (ii, col) in zip(self._titles, self._cols)]))

        ##
        # Data.
        ##
        for dd in flow_db.field_values_in_order(self._field_type_select_get(),
                                                self._column_sort_select):
            rc.append(" ".join([ii.fmt(dd, col.width)
                                for (ii, col) in zip(self._datas,
                                                     self._cols)]))

        return rc


def curses_screen_begin():
    """ begin curses screen control. """
    stdscr = curses.initscr()
    curses.cbreak()
    curses.noecho()
    stdscr.keypad(1)
    return stdscr


def curses_screen_end(stdscr):
    """ end curses screen control. """
    curses.nocbreak()
    stdscr.keypad(0)
    curses.echo()
    curses.endwin()


class FlowDB:
    """ Implements live vs accumulate mode.

    Flows are stored as key value pairs. The key consists of the content
    prior to stat fields. The value portion consists of stats in a dictionary
    form.

    @ \todo future add filtering here.
    """
    def __init__(self, accumulate):
        self._accumulate = accumulate
        self._error_count = 0
        # Values are (stats, last update time.)
        # The last update time is used for aging.
        self._flow_lock = threading.Lock()
        # This dictionary holds individual flows.
        self._flows = {}
        # This dictionary holds aggregate of flow fields.
        self._fields = {}

    def accumulate_get(self):
        """ Return the current accumulate state. """
        return self._accumulate

    def accumulate_toggle(self):
        """ toggle accumulate flow behavior. """
        self._accumulate = not self._accumulate

    def begin(self):
        """ Indicate the beginning of processing flow content.
        if accumulate is false clear current set of flows. """

        if (not self._accumulate):
            self._flow_lock.acquire()
            try:
                self._flows.clear()
            finally:
                self._flow_lock.release()
            self._fields.clear()

    def flow_line_add(self, line):
        """ Split a line from a ovs-dpctl dump-flow into key and stats.
        The order of the content in the flow should be:
        - flow content
        - stats for the flow
        - actions

        This method also assumes that the dump flow output does not
        change order of fields of the same flow.
        """

        line = line.rstrip("\n")
        (fields, stats, _) = flow_line_split(line)

        try:
            fields_dict = elements_to_dict(fields)

            if (len(fields_dict) == 0):
                raise ValueError("flow fields are missing %s", line)

            stats_dict = elements_to_dict(stats)
            if (len(stats_dict) == 0):
                raise ValueError("statistics are missing %s.", line)

            ##
            # In accumulate mode, the Flow database can reach 10,000's of
            # persistent flows. The interaction of the script with this many
            # flows is too slow. Instead, delta are sent to the flow_db
            # database allow incremental changes to be done in O(m) time
            # where m is the current flow list, instead of iterating over
            # all flows in O(n) time where n is the entire history of flows.
            key = ",".join(fields)

            self._flow_lock.acquire()
            try:
                (stats_old_dict, _) = self._flows.get(key, (None, None))
            finally:
                self._flow_lock.release()

            self.flow_event(fields_dict, stats_old_dict, stats_dict)

        except ValueError, arg:
            logging.error(arg)
            self._error_count += 1
            raise

        self._flow_lock.acquire()
        try:
            self._flows[key] = (stats_dict, datetime.datetime.now())
        finally:
            self._flow_lock.release()

    def decay(self, decayTimeInSeconds):
        """ Decay content. """
        now = datetime.datetime.now()
        for (key, value) in self._flows.items():
            (stats_dict, updateTime) = value
            delta = now - updateTime

            if (delta.seconds > decayTimeInSeconds):
                self._flow_lock.acquire()
                try:
                    del self._flows[key]

                    fields_dict = elements_to_dict(flow_line_iter(key))
                    matches = flow_aggregate(fields_dict, stats_dict)
                    for match in matches:
                        self.field_dec(match)

                finally:
                    self._flow_lock.release()

    def flow_stats_get(self):
        """ Return statistics in a form of a dictionary. """
        rc = None
        self._flow_lock.acquire()
        try:
            rc = {"flow_total": len(self._flows),
                  "flow_errors": self._error_count}
        finally:
            self._flow_lock.release()
        return rc

    def field_types_get(self):
        """ Return the set of types stored in the singleton. """
        types = set((ii.field_type for ii in self._fields.values()))
        return types

    def field_add(self, data):
        """ Collect dump-flow data to sum number of times item appears. """
        current = self._fields.get(repr(data), None)
        if (current is None):
            current = copy.copy(data)
        else:
            current += data
        self._fields[repr(current)] = current

    def field_dec(self, data):
        """ Collect dump-flow data to sum number of times item appears. """
        current = self._fields.get(repr(data), None)
        if (current is None):
            raise ValueError("decrementing field missing %s" % repr(data))

        current -= data
        self._fields[repr(current)] = current
        if (current.count == 0):
            del self._fields[repr(current)]

    def field_values_in_order(self, field_type_select, column_order):
        """ Return a list of items in order maximum first. """
        values = self._fields.values()
        if (field_type_select != "all"):
            # If a field type other than "all" then reduce the list.
            values = [ii for ii in values
                      if (ii.field_type == field_type_select)]
        values = [(column_picker(column_order, ii), ii) for ii in values]
        values.sort(key=operator.itemgetter(0))
        values.reverse()
        values = [ii[1] for ii in values]
        return values

    def flow_event(self, fields_dict, stats_old_dict, stats_new_dict):
        """ Receives new flow information. """

        # In order to avoid processing every flow at every sample
        # period, changes in flow packet count is used to determine the
        # delta in the flow statistics. This delta is used in the call
        # to self.decrement prior to self.field_add

        if (stats_old_dict is None):
            # This is a new flow
            matches = flow_aggregate(fields_dict, stats_new_dict)
            for match in matches:
                self.field_add(match)
        else:
            old_packets = int(stats_old_dict.get("packets", 0))
            new_packets = int(stats_new_dict.get("packets", 0))
            if (old_packets == new_packets):
                # ignore. same data.
                pass
            else:
                old_bytes = stats_old_dict.get("bytes", 0)
                # old_packets != new_packets
                # if old_packets > new_packets then we end up decrementing
                # packets and bytes.
                matches = flow_aggregate(fields_dict, stats_new_dict)
                for match in matches:
                    match.decrement(int(old_packets), int(old_bytes), 1)
                    self.field_add(match)


class DecayThread(threading.Thread):
    """ Periodically call flow database to see if any flows are old. """
    def __init__(self, flow_db, interval):
        """ Start decay thread. """
        threading.Thread.__init__(self)

        self._interval = max(1, interval)
        self._min_interval = min(1, interval / 10)
        self._flow_db = flow_db
        self._event = threading.Event()
        self._running = True

        self.daemon = True

    def run(self):
        """ Worker thread which handles decaying accumulated flows. """

        while(self._running):
            self._event.wait(self._min_interval)
            if (self._running):
                self._flow_db.decay(self._interval)

    def stop(self):
        """ Stop thread. """
        self._running = False
        self._event.set()
        ##
        # Give the calling thread time to terminate but not too long.
        # this thread is a daemon so the application will terminate if
        # we timeout during the join. This is just a cleaner way to
        # release resources.
        self.join(2.0)


def flow_top_command(stdscr, render, flow_db):
    """ Handle input while in top mode. """
    ch = stdscr.getch()
    ##
    # Any character will restart sampling.
    if (ch == ord('h')):
        # halt output.
        ch = stdscr.getch()
        while (ch == -1):
            ch = stdscr.getch()

    if (ch == ord('s')):
        # toggle which column sorts data in descending order.
        render.column_select_event()
    elif (ch == ord('a')):
        flow_db.accumulate_toggle()
    elif (ch == ord('f')):
        render.field_type_toggle()
    elif (ch == ord(' ')):
        # resample
        pass

    return ch


def decay_timer_start(flow_db, accumulateDecay):
    """ If accumulateDecay greater than zero then start timer. """
    if (accumulateDecay > 0):
        decay_timer = DecayThread(flow_db, accumulateDecay)
        decay_timer.start()
        return decay_timer
    else:
        return None


def flows_top(args):
    """ handles top like behavior when --script is not specified. """

    flow_db = FlowDB(args.accumulate)
    render = Render(0, Render.FIELD_SELECT_TOP)

    decay_timer = decay_timer_start(flow_db, args.accumulateDecay)
    lines = []

    try:
        stdscr = curses_screen_begin()
        try:
            ch = 'X'
            #stdscr.nodelay(1)
            stdscr.timeout(args.delay)

            while (ch != ord('q')):
                flow_db.begin()

                try:
                    ihdl = top_input_get(args)
                    try:
                        flows_read(ihdl, flow_db)
                    finally:
                        ihdl.close()
                except OSError, arg:
                    logging.critical(arg)
                    break

                (console_height, console_width) = stdscr.getmaxyx()
                render.console_width_set(console_width)

                output_height = console_height - 1
                line_count = range(output_height)
                line_output = render.format(flow_db)
                lines = zip(line_count, line_output[:output_height])

                stdscr.erase()
                for (count, line) in lines:
                    stdscr.addstr(count, 0, line[:console_width])
                stdscr.refresh()

                ch = flow_top_command(stdscr, render, flow_db)

        finally:
            curses_screen_end(stdscr)
    except KeyboardInterrupt:
        pass
    if (decay_timer):
        decay_timer.stop()

    # repeat output
    for (count, line) in lines:
        print line


def flows_script(args):
    """ handles --script option. """

    flow_db = FlowDB(args.accumulate)
    flow_db.begin()

    if (args.flowFiles is None):
        logging.info("reading flows from stdin")
        ihdl = os.fdopen(sys.stdin.fileno(), 'r', 0)
        try:
            flow_db = flows_read(ihdl, flow_db)
        finally:
            ihdl.close()
    else:
        for flowFile in args.flowFiles:
            logging.info("reading flows from %s", flowFile)
            ihdl = open(flowFile, "r")
            try:
                flow_db = flows_read(ihdl, flow_db)
            finally:
                ihdl.close()

    (_, console_width) = get_terminal_size()
    render = Render(console_width, Render.FIELD_SELECT_SCRIPT)

    for line in render.format(flow_db):
        print line


def main():
    """ Return 0 on success or 1 on failure.

    Algorithm
    There are four stages to the process ovs-dpctl dump-flow content.
    1. Retrieve current input
    2. store in FlowDB and maintain history
    3. Iterate over FlowDB and aggregating stats for each flow field
    4. present data.

    Retrieving current input is currently trivial, the ovs-dpctl dump-flow
    is called. Future version will have more elaborate means for collecting
    dump-flow content. FlowDB returns all data as in the form of a hierarchical
    dictionary. Input will vary.

    In the case of accumulate mode, flows are not purged from the FlowDB
    manager. Instead at the very least, merely the latest statistics are
    kept. In the case, of live output the FlowDB is purged prior to sampling
    data.

    Aggregating results requires identify flow fields to aggregate out
    of the flow and summing stats.

    """
    args = args_get()

    try:
        if (args.top):
            flows_top(args)
        else:
            flows_script(args)
    except KeyboardInterrupt:
        return 1
    return 0

if __name__ == '__main__':
    sys.exit(main())
elif __name__ == 'ovs-dpctl-top':
    # pylint: disable-msg=R0915

    ##
    # Test case beyond this point.
    # pylint: disable-msg=R0904
    class TestsuiteFlowParse(unittest.TestCase):
        """
        parse flow into hierarchy of dictionaries.
        """
        def test_flow_parse(self):
            """ test_flow_parse. """
            line = "in_port(4),eth(src=00:50:56:b4:4e:f8,"\
                   "dst=33:33:00:01:00:03),eth_type(0x86dd),"\
                   "ipv6(src=fe80::55bf:fe42:bc96:2812,dst=ff02::1:3,"\
                   "label=0,proto=17,tclass=0,hlimit=1,frag=no),"\
                   "udp(src=61252,dst=5355), packets:1, bytes:92, "\
                   "used:0.703s, actions:3,8,11,14,17,20,23,26,29,32,35,"\
                   "38,41,44,47,50,53,56,59,62,65"

            (fields, stats, _) = flow_line_split(line)
            flow_dict = elements_to_dict(fields + stats)
            self.assertEqual(flow_dict["eth"]["src"], "00:50:56:b4:4e:f8")
            self.assertEqual(flow_dict["eth"]["dst"], "33:33:00:01:00:03")
            self.assertEqual(flow_dict["ipv6"]["src"],
                             "fe80::55bf:fe42:bc96:2812")
            self.assertEqual(flow_dict["ipv6"]["dst"], "ff02::1:3")
            self.assertEqual(flow_dict["packets"], "1")
            self.assertEqual(flow_dict["bytes"], "92")

            line = "in_port(4),eth(src=00:50:56:b4:4e:f8,"\
                   "dst=33:33:00:01:00:03),eth_type(0x86dd),"\
                   "ipv6(src=fe80::55bf:fe42:bc96:2812,dst=ff02::1:3,"\
                   "label=0,proto=17,tclass=0,hlimit=1,frag=no),"\
                   "udp(src=61252,dst=5355), packets:1, bytes:92, "\
                   "used:-0.703s, actions:3,8,11,14,17,20,23,26,29,32,35,"\
                   "38,41,44,47,50,53,56,59,62,65"

            (fields, stats, _) = flow_line_split(line)
            flow_dict = elements_to_dict(fields + stats)
            self.assertEqual(flow_dict["used"], "-0.703s")
            self.assertEqual(flow_dict["packets"], "1")
            self.assertEqual(flow_dict["bytes"], "92")

        def test_flow_sum(self):
            """ test_flow_sum. """
            line = "in_port(4),eth(src=00:50:56:b4:4e:f8,"\
                   "dst=33:33:00:01:00:03),eth_type(0x86dd),"\
                   "ipv6(src=fe80::55bf:fe42:bc96:2812,dst=ff02::1:3,"\
                   "label=0,proto=17,tclass=0,hlimit=1,frag=no),"\
                   "udp(src=61252,dst=5355), packets:2, bytes:92, "\
                   "used:0.703s, actions:3,8,11,14,17,20,23,26,29,32,35,"\
                   "38,41,44,47,50,53,56,59,62,65"

            (fields, stats, _) = flow_line_split(line)
            stats_dict = elements_to_dict(stats)
            fields_dict = elements_to_dict(fields)
            ##
            # Test simple case of one line.
            flow_db = FlowDB(False)
            matches = flow_aggregate(fields_dict, stats_dict)
            for match in matches:
                flow_db.field_add(match)

            flow_types = flow_db.field_types_get()
            expected_flow_types = ["eth", "eth_type", "udp", "in_port", "ipv6"]
            self.assert_(len(flow_types) == len(expected_flow_types))
            for flow_type in flow_types:
                self.assertTrue(flow_type in expected_flow_types)

            for flow_type in flow_types:
                sum_value = flow_db.field_values_in_order("all", 1)
                self.assert_(len(sum_value) == 5)
                self.assert_(sum_value[0].packets == 2)
                self.assert_(sum_value[0].count == 1)
                self.assert_(sum_value[0].bytes == 92)

            ##
            # Add line again just to see counts go up.
            matches = flow_aggregate(fields_dict, stats_dict)
            for match in matches:
                flow_db.field_add(match)

            flow_types = flow_db.field_types_get()
            self.assert_(len(flow_types) == len(expected_flow_types))
            for flow_type in flow_types:
                self.assertTrue(flow_type in expected_flow_types)

            for flow_type in flow_types:
                sum_value = flow_db.field_values_in_order("all", 1)
                self.assert_(len(sum_value) == 5)
                self.assert_(sum_value[0].packets == 4)
                self.assert_(sum_value[0].count == 2)
                self.assert_(sum_value[0].bytes == 2 * 92)

        def test_assoc_list(self):
            """ test_assoc_list. """
            line = "in_port(4),eth(src=00:50:56:b4:4e:f8,"\
                   "dst=33:33:00:01:00:03),eth_type(0x86dd),"\
                   "ipv6(src=fe80::55bf:fe42:bc96:2812,dst=ff02::1:3,"\
                   "label=0,proto=17,tclass=0,hlimit=1,frag=no),"\
                   "udp(src=61252,dst=5355), packets:2, bytes:92, "\
                   "used:0.703s, actions:3,8,11,14,17,20,23,26,29,32,35,"\
                   "38,41,44,47,50,53,56,59,62,65"

            valid_flows = [
                'eth_type(0x86dd)',
                'udp(dst=5355)',
                'in_port(4)',
                'ipv6(src=fe80::55bf:fe42:bc96:2812,dst=ff02::1:3)',
                'eth(src=00:50:56:b4:4e:f8,dst=33:33:00:01:00:03)'
                ]

            (fields, stats, _) = flow_line_split(line)
            stats_dict = elements_to_dict(stats)
            fields_dict = elements_to_dict(fields)

            ##
            # Test simple case of one line.
            flow_db = FlowDB(False)
            matches = flow_aggregate(fields_dict, stats_dict)
            for match in matches:
                flow_db.field_add(match)

            for sum_value in flow_db.field_values_in_order("all", 1):
                assoc_list = Columns.assoc_list(sum_value)
                for item in assoc_list:
                    if (item[0] == "fields"):
                        self.assertTrue(item[1] in valid_flows)
                    elif (item[0] == "packets"):
                        self.assertTrue(item[1] == 2)
                    elif (item[0] == "count"):
                        self.assertTrue(item[1] == 1)
                    elif (item[0] == "average"):
                        self.assertTrue(item[1] == 46.0)
                    elif (item[0] == "bytes"):
                        self.assertTrue(item[1] == 92)
                    else:
                        raise ValueError("unknown %s", item[0])

        def test_human_format(self):
            """ test_assoc_list. """

            self.assertEqual(approximate_size(0.0), "0.0 KiB")
            self.assertEqual(approximate_size(1024), "1.0 KiB")
            self.assertEqual(approximate_size(1024 * 1024), "1.0 MiB")
            self.assertEqual(approximate_size((1024 * 1024) + 100000),
                             "1.1 MiB")
            value = (1024 * 1024 * 1024) + 100000000
            self.assertEqual(approximate_size(value), "1.1 GiB")

        def test_flow_line_split(self):
            """ Splitting a flow line is not trivial.
            There is no clear delimiter. Comma is used liberally."""
            expected_fields = ["in_port(4)",
                            "eth(src=00:50:56:b4:4e:f8,dst=33:33:00:01:00:03)",
                            "eth_type(0x86dd)",
                           "ipv6(src=fe80::55bf:fe42:bc96:2812,dst=ff02::1:3,"
                           "label=0,proto=17,tclass=0,hlimit=1,frag=no)",
                           "udp(src=61252,dst=5355)"]
            expected_stats = ["packets:2", "bytes:92", "used:0.703s"]
            expected_actions = "actions:3,8,11,14,17,20,23,26,29,32,35," \
                               "38,41,44,47,50,53,56,59,62,65"

            line = "in_port(4),eth(src=00:50:56:b4:4e:f8,"\
                   "dst=33:33:00:01:00:03),eth_type(0x86dd),"\
                   "ipv6(src=fe80::55bf:fe42:bc96:2812,dst=ff02::1:3,"\
                   "label=0,proto=17,tclass=0,hlimit=1,frag=no),"\
                   "udp(src=61252,dst=5355), packets:2, bytes:92, "\
                   "used:0.703s, actions:3,8,11,14,17,20,23,26,29,32,35,"\
                   "38,41,44,47,50,53,56,59,62,65"

            (fields, stats, actions) = flow_line_split(line)

            self.assertEqual(fields, expected_fields)
            self.assertEqual(stats, expected_stats)
            self.assertEqual(actions, expected_actions)

        def test_accumulate_decay(self):
            """ test_accumulate_decay: test accumulated decay. """
            lines = ["in_port(1),eth(src=00:50:56:4f:dc:3b,"
                     "dst=ff:ff:ff:ff:ff:ff),"
                     "eth_type(0x0806),arp(sip=10.24.105.107/255.255.255.255,"
                     "tip=10.24.104.230/255.255.255.255,op=1/0xff,"
                     "sha=00:50:56:4f:dc:3b/00:00:00:00:00:00,"
                     "tha=00:00:00:00:00:00/00:00:00:00:00:00), "
                     "packets:1, bytes:120, used:0.004s, actions:1"]

            flow_db = FlowDB(True)
            flow_db.begin()
            flow_db.flow_line_add(lines[0])

            # Make sure we decay
            time.sleep(4)
            self.assertEqual(flow_db.flow_stats_get()["flow_total"], 1)
            flow_db.decay(1)
            self.assertEqual(flow_db.flow_stats_get()["flow_total"], 0)

            flow_db.flow_line_add(lines[0])
            self.assertEqual(flow_db.flow_stats_get()["flow_total"], 1)
            flow_db.decay(30)
            # Should not be deleted.
            self.assertEqual(flow_db.flow_stats_get()["flow_total"], 1)

            flow_db.flow_line_add(lines[0])
            self.assertEqual(flow_db.flow_stats_get()["flow_total"], 1)
            timer = decay_timer_start(flow_db, 2)
            time.sleep(10)
            self.assertEqual(flow_db.flow_stats_get()["flow_total"], 0)
            timer.stop()

        def test_accumulate(self):
            """ test_accumulate test that FlowDB supports accumulate. """

            lines = ["in_port(1),eth(src=00:50:56:4f:dc:3b,"
                     "dst=ff:ff:ff:ff:ff:ff),"
                     "eth_type(0x0806),arp(sip=10.24.105.107/255.255.255.255,"
                     "tip=10.24.104.230/255.255.255.255,op=1/0xff,"
                     "sha=00:50:56:4f:dc:3b/00:00:00:00:00:00,"
                     "tha=00:00:00:00:00:00/00:00:00:00:00:00), "
                     "packets:1, bytes:120, used:0.004s, actions:1",
                     "in_port(2),"
                     "eth(src=68:ef:bd:25:ef:c0,dst=33:33:00:00:00:66),"
                     "eth_type(0x86dd),ipv6(src=fe80::6aef:bdff:fe25:efc0/::,"
                     "dst=ff02::66/::,label=0/0,proto=17/0xff,tclass=0xe0/0,"
                     "hlimit=255/0,frag=no/0),udp(src=2029,dst=2029), "
                     "packets:2, bytes:5026, used:0.348s, actions:1",
                     "in_port(1),eth(src=ee:ee:ee:ee:ee:ee,"
                     "dst=ff:ff:ff:ff:ff:ff),"
                     "eth_type(0x0806),arp(sip=10.24.105.107/255.255.255.255,"
                     "tip=10.24.104.230/255.255.255.255,op=1/0xff,"
                     "sha=00:50:56:4f:dc:3b/00:00:00:00:00:00,"
                     "tha=00:00:00:00:00:00/00:00:00:00:00:00), packets:2, "
                     "bytes:240, used:0.004s, actions:1"]

            lines = [
                "in_port(1),eth_type(0x0806), packets:1, bytes:120, actions:1",
                "in_port(2),eth_type(0x0806), packets:2, bytes:126, actions:1",
                "in_port(1),eth_type(0x0806), packets:2, bytes:240, actions:1",
                "in_port(1),eth_type(0x0800), packets:1, bytes:120, actions:1",
                "in_port(1),eth_type(0x0800), packets:2, bytes:240, actions:1",
                "in_port(1),eth_type(0x0806), packets:1, bytes:120, actions:1",
                ]

            # Turn on accumulate.
            flow_db = FlowDB(True)
            flow_db.begin()

            flow_db.flow_line_add(lines[0])

            # Test one flow exist.
            sum_values = flow_db.field_values_in_order("all", 1)
            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(1)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 1)
            self.assertEqual(in_ports[0].bytes, 120)
            self.assertEqual(in_ports[0].count, 1)

            # simulate another sample
            # Test two different flows exist.
            flow_db.begin()
            flow_db.flow_line_add(lines[1])
            sum_values = flow_db.field_values_in_order("all", 1)
            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(1)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 1)
            self.assertEqual(in_ports[0].bytes, 120)
            self.assertEqual(in_ports[0].count, 1)

            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(2)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 2)
            self.assertEqual(in_ports[0].bytes, 126)
            self.assertEqual(in_ports[0].count, 1)

            # Test first flow increments packets.
            flow_db.begin()
            flow_db.flow_line_add(lines[2])
            sum_values = flow_db.field_values_in_order("all", 1)
            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(1)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 2)
            self.assertEqual(in_ports[0].bytes, 240)
            self.assertEqual(in_ports[0].count, 1)

            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(2)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 2)
            self.assertEqual(in_ports[0].bytes, 126)
            self.assertEqual(in_ports[0].count, 1)

            # Test third flow but with the same in_port(1) as the first flow.
            flow_db.begin()
            flow_db.flow_line_add(lines[3])
            sum_values = flow_db.field_values_in_order("all", 1)
            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(1)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 3)
            self.assertEqual(in_ports[0].bytes, 360)
            self.assertEqual(in_ports[0].count, 2)

            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(2)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 2)
            self.assertEqual(in_ports[0].bytes, 126)
            self.assertEqual(in_ports[0].count, 1)

            # Third flow has changes.
            flow_db.begin()
            flow_db.flow_line_add(lines[4])
            sum_values = flow_db.field_values_in_order("all", 1)
            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(1)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 4)
            self.assertEqual(in_ports[0].bytes, 480)
            self.assertEqual(in_ports[0].count, 2)

            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(2)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 2)
            self.assertEqual(in_ports[0].bytes, 126)
            self.assertEqual(in_ports[0].count, 1)

            # First flow reset.
            flow_db.begin()
            flow_db.flow_line_add(lines[5])
            sum_values = flow_db.field_values_in_order("all", 1)
            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(1)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 3)
            self.assertEqual(in_ports[0].bytes, 360)
            self.assertEqual(in_ports[0].count, 2)

            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(2)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 2)
            self.assertEqual(in_ports[0].bytes, 126)
            self.assertEqual(in_ports[0].count, 1)

        def test_parse_character_errors(self):
            """ test_parsing errors.
            The flow parses is purposely loose. Its not designed to validate
            input. Merely pull out what it can but there are situations
            that a parse error can be detected.
            """

            lines = ["complete garbage",
                     "in_port(2),eth(src=68:ef:bd:25:ef:c0,"
                     "dst=33:33:00:00:00:66),"
                     "eth_type(0x86dd),ipv6(src=fe80::6aef:bdff:fe25:efc0/::,"
                     "dst=ff02::66/::,label=0/0,proto=17/0xff,tclass=0xe0/0,"
                     "hlimit=255/0,frag=no/0),udp(src=2029,dst=2029),"
                     "packets:2,bytes:5026,actions:1"]

            flow_db = FlowDB(False)
            flow_db.begin()
            for line in lines:
                try:
                    flow_db.flow_line_add(line)
                except ValueError:
                    # We want an exception. That is how we know we have
                    # correctly found a simple parsing error. We are not
                    # looking to validate flow output just catch simple issues.
                    continue
                self.assertTrue(False)

        def test_tunnel_parsing(self):
            """ test_tunnel_parsing test parse flows with tunnel. """
            lines = [
                "tunnel(tun_id=0x0,src=192.168.1.1,dst=192.168.1.10,"
                "tos=0x0,ttl=64,flags(key)),in_port(1),"
                "eth(src=9e:40:f5:ef:ec:ee,dst=01:23:20:00:00:30),"
                "eth_type(0x8902), packets:6, bytes:534, used:0.128s, "
                "actions:userspace(pid=4294962691,slow_path(cfm))"
                ]
            flow_db = FlowDB(False)
            flow_db.begin()
            flow_db.flow_line_add(lines[0])
            sum_values = flow_db.field_values_in_order("all", 1)
            in_ports = [ii for ii in sum_values if (repr(ii) == "in_port(1)")]
            self.assertEqual(len(in_ports), 1)
            self.assertEqual(in_ports[0].packets, 6)
            self.assertEqual(in_ports[0].bytes, 534)
            self.assertEqual(in_ports[0].count, 1)

        def test_flow_multiple_paren(self):
            """ test_flow_multiple_paren. """
            line = "tunnel(tun_id=0x0,src=192.168.1.1,flags(key)),in_port(2)"
            valid = ["tunnel(tun_id=0x0,src=192.168.1.1,flags(key))",
                     "in_port(2)"]
            rc = flow_line_iter(line)
            self.assertEqual(valid, rc)

        def test_to_network(self):
            """ test_to_network test ipv4_to_network and ipv6_to_network. """
            ipv4s = [
                ("192.168.0.1", "192.168.0.1"),
                ("192.168.0.1/255.255.255.255", "192.168.0.1"),
                ("192.168.0.1/255.255.255.0", "192.168.0.0"),
                ("192.168.0.1/255.255.0.0", "192.168.0.0"),
                ("192.168.0.1/255.0.0.0", "192.0.0.0"),
                ("192.168.0.1/0.0.0.0", "0.0.0.0"),
                ("10.24.106.230/255.255.255.255", "10.24.106.230"),
                ("10.24.106.230/255.255.255.0", "10.24.106.0"),
                ("10.24.106.0/255.255.255.0", "10.24.106.0"),
                ("10.24.106.0/255.255.252.0", "10.24.104.0")
                ]

            ipv6s = [
                ("1::192:168:0:1", "1::192:168:0:1"),
                ("1::192:168:0:1/1::ffff:ffff:ffff:ffff", "1::192:168:0:1"),
                ("1::192:168:0:1/1::ffff:ffff:ffff:0", "1::192:168:0:0"),
                ("1::192:168:0:1/1::ffff:ffff:0:0", "1::192:168:0:0"),
                ("1::192:168:0:1/1::ffff:0:0:0", "1::192:0:0:0"),
                ("1::192:168:0:1/1::0:0:0:0", "1::"),
                ("1::192:168:0:1/::", "::")
                ]

            for (ipv4_test, ipv4_check) in ipv4s:
                self.assertEqual(ipv4_to_network(ipv4_test), ipv4_check)

            for (ipv6_test, ipv6_check) in ipv6s:
                self.assertEqual(ipv6_to_network(ipv6_test), ipv6_check)

        def test_ui(self):
            """ test_ui: test expected ui behavior. """
            #pylint: disable=W0212
            top_render = Render(80, Render.FIELD_SELECT_TOP)
            script_render = Render(80, Render.FIELD_SELECT_SCRIPT)
            self.assertEqual(top_render._field_type_select_get(), "in_port")
            self.assertEqual(script_render._field_type_select_get(), "all")
            #pylint: enable=W0212