summaryrefslogtreecommitdiffstats
path: root/docs/manual/mod/mod_lua.html.en
blob: 52cdcf889722b64125cc3cf26cb0438ea91e72f8 (plain)
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
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head>
<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" />
<!--
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
              This file is generated from xml source: DO NOT EDIT
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
      -->
<title>mod_lua - Apache HTTP Server Version 2.4</title>
<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="../style/css/prettify.css" />
<script src="../style/scripts/prettify.min.js" type="text/javascript">
</script>

<link href="../images/favicon.ico" rel="shortcut icon" /></head>
<body>
<div id="page-header">
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
<p class="apache">Apache HTTP Server Version 2.4</p>
<img alt="" src="../images/feather.png" /></div>
<div class="up"><a href="./"><img title="&lt;-" alt="&lt;-" src="../images/left.gif" /></a></div>
<div id="path">
<a href="http://www.apache.org/">Apache</a> &gt; <a href="http://httpd.apache.org/">HTTP Server</a> &gt; <a href="http://httpd.apache.org/docs/">Documentation</a> &gt; <a href="../">Version 2.4</a> &gt; <a href="./">Modules</a></div>
<div id="page-content">
<div id="preamble"><h1>Apache Module mod_lua</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="../en/mod/mod_lua.html" title="English">&nbsp;en&nbsp;</a> |
<a href="../fr/mod/mod_lua.html" hreflang="fr" rel="alternate" title="Français">&nbsp;fr&nbsp;</a></p>
</div>
<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Provides Lua hooks into various portions of the httpd
request processing</td></tr>
<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>lua_module</td></tr>
<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_lua.c</td></tr>
<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>2.3 and later</td></tr></table>
<h3>Summary</h3>

<p>This module allows the server to be extended with scripts written in the
Lua programming language.  The extension points (hooks) available with
<code class="module"><a href="../mod/mod_lua.html">mod_lua</a></code> include many of the hooks available to
natively compiled Apache HTTP Server modules, such as mapping requests to
files, generating dynamic responses, access control, authentication, and
authorization</p>

<p>More information on the Lua programming language can be found at the
<a href="http://www.lua.org/">the Lua website</a>.</p>

<div class="warning"><h3>Warning</h3>
<p>This module holds a great deal of power over httpd, which is both a 
strength and a potential security risk. It is <strong>not</strong> recommended 
that you use this module on a server that is shared with users you do not 
trust, as it can be abused to change the internal workings of httpd.</p>
</div>

</div>
<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><h3>Topics</h3>
<ul id="topics">
<li><img alt="" src="../images/down.gif" /> <a href="#basicconf">Basic Configuration</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#writinghandlers">Writing Handlers</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#writingauthzproviders">Writing Authorization Providers</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#writinghooks">Writing Hooks</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#datastructures">Data Structures</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#functions">Built in functions</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#logging">Logging Functions</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#apache2">apache2 Package</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#modifying_buckets">Modifying contents with Lua filters</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#databases">Database connectivity</a></li>
</ul><h3 class="directives">Directives</h3>
<ul id="toc">
<li><img alt="" src="../images/down.gif" /> <a href="#luaauthzprovider">LuaAuthzProvider</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luacodecache">LuaCodeCache</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahookaccesschecker">LuaHookAccessChecker</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahookauthchecker">LuaHookAuthChecker</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahookcheckuserid">LuaHookCheckUserID</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahookfixups">LuaHookFixups</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahookinsertfilter">LuaHookInsertFilter</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahooklog">LuaHookLog</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahookmaptostorage">LuaHookMapToStorage</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahookpretranslate">LuaHookPreTranslate</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahooktranslatename">LuaHookTranslateName</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luahooktypechecker">LuaHookTypeChecker</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luainherit">LuaInherit</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luainputfilter">LuaInputFilter</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luamaphandler">LuaMapHandler</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luaoutputfilter">LuaOutputFilter</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luapackagecpath">LuaPackageCPath</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luapackagepath">LuaPackagePath</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luaquickhandler">LuaQuickHandler</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luaroot">LuaRoot</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#luascope">LuaScope</a></li>
</ul>
<h3>Bugfix checklist</h3><ul class="seealso"><li><a href="https://www.apache.org/dist/httpd/CHANGES_2.4">httpd changelog</a></li><li><a href="https://bz.apache.org/bugzilla/buglist.cgi?bug_status=__open__&amp;list_id=144532&amp;product=Apache%20httpd-2&amp;query_format=specific&amp;order=changeddate%20DESC%2Cpriority%2Cbug_severity&amp;component=mod_lua">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&amp;component=mod_lua">Report a bug</a></li></ul><h3>See also</h3>
<ul class="seealso">
<li><a href="#comments_section">Comments</a></li></ul></div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="basicconf" id="basicconf">Basic Configuration</a></h2>

<p>The basic module loading directive is</p>

<pre class="prettyprint lang-config">LoadModule lua_module modules/mod_lua.so</pre>


<p>
<code>mod_lua</code> provides a handler named <code>lua-script</code>,
which can be used with a <code class="directive"><a href="../mod/core.html#sethandler">SetHandler</a></code> or
<code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code> directive:</p>

<pre class="prettyprint lang-config">&lt;Files "*.lua"&gt;
    SetHandler lua-script
&lt;/Files&gt;</pre>


<p>
This will cause <code>mod_lua</code> to handle requests for files
ending in <code>.lua</code> by invoking that file's
<code>handle</code> function.
</p>

<p>For more flexibility, see <code class="directive">LuaMapHandler</code>.
</p>

</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="writinghandlers" id="writinghandlers">Writing Handlers</a></h2>
<p> In the Apache HTTP Server API, the handler is a specific kind of hook
responsible for generating the response.  Examples of modules that include a
handler are <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>, <code class="module"><a href="../mod/mod_cgi.html">mod_cgi</a></code>,
and <code class="module"><a href="../mod/mod_status.html">mod_status</a></code>.</p>

<p><code>mod_lua</code> always looks to invoke a Lua function for the handler, rather than
just evaluating a script body CGI style. A handler function looks
something like this:</p>


<pre class="prettyprint lang-lua">
<strong>example.lua</strong><br />
-- example handler

require "string"

--[[
     This is the default method name for Lua handlers, see the optional
     function-name in the LuaMapHandler directive to choose a different
     entry point.
--]]
function handle(r)
    r.content_type = "text/plain"

    if r.method == 'GET' then
        r:puts("Hello Lua World!\n")
        for k, v in pairs( r:parseargs() ) do
            r:puts( string.format("%s: %s\n", k, v) )
        end
    elseif r.method == 'POST' then
        r:puts("Hello Lua World!\n")
        for k, v in pairs( r:parsebody() ) do
            r:puts( string.format("%s: %s\n", k, v) )
        end
    elseif r.method == 'PUT' then
-- use our own Error contents
        r:puts("Unsupported HTTP method " .. r.method)
        r.status = 405
        return apache2.OK
    else
-- use the ErrorDocument
        return 501
    end
    return apache2.OK
end</pre>


<p>
This handler function just prints out the uri or form encoded
arguments to a plaintext page.
</p>

<p>
This means (and in fact encourages) that you can have multiple
handlers (or hooks, or filters) in the same script.
</p>

</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="writingauthzproviders" id="writingauthzproviders">Writing Authorization Providers</a></h2>


<p><code class="module"><a href="../mod/mod_authz_core.html">mod_authz_core</a></code> provides a high-level interface to
authorization that is much easier to use than using into the relevant
hooks directly. The first argument to the
<code class="directive"><a href="../mod/mod_authz_core.html#require">Require</a></code> directive gives
the name of the responsible authorization provider. For any
<code class="directive"><a href="../mod/mod_authz_core.html#require">Require</a></code> line,
<code class="module"><a href="../mod/mod_authz_core.html">mod_authz_core</a></code> will call the authorization provider
of the given name, passing the rest of the line as parameters. The
provider will then check authorization and pass the result as return
value.</p>

<p>The authz provider is normally called before authentication. If it needs to
know the authenticated user name (or if the user will be authenticated at
all), the provider must return <code>apache2.AUTHZ_DENIED_NO_USER</code>.
This will cause authentication to proceed and the authz provider to be
called a second time.</p>

<p>The following authz provider function takes two arguments, one ip
address and one user name. It will allow access from the given ip address
without authentication, or if the authenticated user matches the second
argument:</p>

<pre class="prettyprint lang-lua">
<strong>authz_provider.lua</strong><br />

require 'apache2'

function authz_check_foo(r, ip, user)
    if r.useragent_ip == ip then
        return apache2.AUTHZ_GRANTED
    elseif r.user == nil then
        return apache2.AUTHZ_DENIED_NO_USER
    elseif r.user == user then
        return apache2.AUTHZ_GRANTED
    else
        return apache2.AUTHZ_DENIED
    end
end</pre>


<p>The following configuration registers this function as provider
<code>foo</code> and configures it for URL <code>/</code>:</p>
<pre class="prettyprint lang-config">LuaAuthzProvider foo authz_provider.lua authz_check_foo
&lt;Location "/"&gt;
  Require foo 10.1.2.3 john_doe
&lt;/Location&gt;</pre>


</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="writinghooks" id="writinghooks">Writing Hooks</a></h2>

<p>Hook functions are how modules (and Lua scripts) participate in the
processing of requests. Each type of hook exposed by the server exists for
a specific purpose, such as mapping requests to the file system,
performing access control, or setting mime types:</p>

<table class="bordered"><tr class="header">
        <th>Hook phase</th>
        <th>mod_lua directive</th>
        <th>Description</th>
    </tr>
<tr>
        <td>Quick handler</td>
        <td><code class="directive"><a href="#luaquickhandler">LuaQuickHandler</a></code></td>
        <td>This is the first hook that will be called after a request has 
            been mapped to a host or virtual host</td>
    </tr>
<tr class="odd">
        <td>Pre-Translate name</td>
        <td><code class="directive"><a href="#luahookpretranslatename">LuaHookPreTranslateName</a></code></td>
        <td>This phase translates the requested URI into a filename on the
            system, before decoding occurs. Modules such as <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>
            can operate in this phase.</td>
    </tr>
<tr>
        <td>Translate name</td>
        <td><code class="directive"><a href="#luahooktranslatename">LuaHookTranslateName</a></code></td>
        <td>This phase translates the requested URI into a filename on the 
            system. Modules such as <code class="module"><a href="../mod/mod_alias.html">mod_alias</a></code> and
            <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> operate in this phase.</td>
    </tr>
<tr class="odd">
        <td>Map to storage</td>
        <td><code class="directive"><a href="#luahookmaptostorage">LuaHookMapToStorage</a></code></td>
        <td>This phase maps files to their physical, cached or external/proxied storage. 
            It can be used by proxy or caching modules</td>
    </tr>
<tr>
        <td>Check Access</td>
        <td><code class="directive"><a href="#luahookaccesschecker">LuaHookAccessChecker</a></code></td>
        <td>This phase checks whether a client has access to a resource. This 
            phase is run before the user is authenticated, so beware.
        </td>
    </tr>
<tr class="odd">
        <td>Check User ID</td>
        <td><code class="directive"><a href="#luahookcheckuserid">LuaHookCheckUserID</a></code></td>
        <td>This phase it used to check the negotiated user ID</td>
    </tr>
<tr>
        <td>Check Authorization</td>
        <td><code class="directive"><a href="#luahookauthchecker">LuaHookAuthChecker</a></code> or 
            <code class="directive"><a href="#luaauthzprovider">LuaAuthzProvider</a></code></td>
        <td>This phase authorizes a user based on the negotiated credentials, such as 
            user ID, client certificate etc.
        </td>
    </tr>
<tr class="odd">
        <td>Check Type</td>
        <td><code class="directive"><a href="#luahooktypechecker">LuaHookTypeChecker</a></code></td>
        <td>This phase checks the requested file and assigns a content type and 
            a handler to it</td>
    </tr>
<tr>
        <td>Fixups</td>
        <td><code class="directive"><a href="#luahookfixups">LuaHookFixups</a></code></td>
        <td>This is the final "fix anything" phase before the content handlers 
            are run. Any last-minute changes to the request should be made here.</td>
    </tr>
<tr class="odd">
        <td>Content handler</td>
        <td>fx. <code>.lua</code> files or through <code class="directive"><a href="#luamaphandler">LuaMapHandler</a></code></td>
        <td>This is where the content is handled. Files are read, parsed, some are run, 
            and the result is sent to the client</td>
    </tr>
<tr>
        <td>Logging</td>
        <td><code class="directive"><a href="#luahooklog">LuaHookLog</a></code></td>
        <td>Once a request has been handled, it enters several logging phases, 
            which logs the request in either the error or access log. Mod_lua
            is able to hook into the start of this and control logging output.</td>
    </tr>
</table>

<p>Hook functions are passed the request object as their only argument 
(except for LuaAuthzProvider, which also gets passed the arguments from 
the Require directive).
They can return any value, depending on the hook, but most commonly
they'll return OK, DONE, or DECLINED, which you can write in Lua as
<code>apache2.OK</code>, <code>apache2.DONE</code>, or
<code>apache2.DECLINED</code>, or else an HTTP status code.</p>


<pre class="prettyprint lang-lua">
<strong>translate_name.lua</strong><br />
-- example hook that rewrites the URI to a filesystem path.

require 'apache2'

function translate_name(r)
    if r.uri == "/translate-name" then
        r.filename = r.document_root .. "/find_me.txt"
        return apache2.OK
    end
    -- we don't care about this URL, give another module a chance
    return apache2.DECLINED
end</pre>



<pre class="prettyprint lang-lua">
<strong>translate_name2.lua</strong><br />
--[[ example hook that rewrites one URI to another URI. It returns a
     apache2.DECLINED to give other URL mappers a chance to work on the
     substitution, including the core translate_name hook which maps based
     on the DocumentRoot.

     Note: Use the early/late flags in the directive to make it run before
           or after mod_alias.
--]]

require 'apache2'

function translate_name(r)
    if r.uri == "/translate-name" then
        r.uri = "/find_me.txt"
        return apache2.DECLINED
    end
    return apache2.DECLINED
end</pre>

</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="datastructures" id="datastructures">Data Structures</a></h2>

<dl>
<dt>request_rec</dt>
        <dd>
        <p>The request_rec is mapped in as a userdata. It has a metatable
        which lets you do useful things with it. For the most part it
        has the same fields as the request_rec struct, many of which are writable as
        well as readable.  (The table fields' content can be changed, but the
        fields themselves cannot be set to different tables.)</p>

        <table class="bordered"><tr class="header">
          <th><strong>Name</strong></th>
          <th><strong>Lua type</strong></th>
          <th><strong>Writable</strong></th>
          <th><strong>Description</strong></th>
        </tr>
<tr>
          <td><code>allowoverrides</code></td>
          <td>string</td>
          <td>no</td>
          <td>The AllowOverride options applied to the current request.</td>
        </tr>
<tr class="odd">
          <td><code>ap_auth_type</code></td>
          <td>string</td>
          <td>no</td>
          <td>If an authentication check was made, this is set to the type 
          of authentication (f.x. <code>basic</code>)</td>
        </tr>
<tr>
          <td><code>args</code></td>
          <td>string</td>
          <td>yes</td>
          <td>The query string arguments extracted from the request 
            (f.x. <code>foo=bar&amp;name=johnsmith</code>)</td>
        </tr>
<tr class="odd">
          <td><code>assbackwards</code></td>
          <td>boolean</td>
          <td>no</td>
          <td>Set to true if this is an HTTP/0.9 style request 
            (e.g. <code>GET /foo</code> (with no headers) )</td>
        </tr>
<tr>
          <td><code>auth_name</code></td>
          <td>string</td>
          <td>no</td>
          <td>The realm name used for authorization (if applicable).</td>
        </tr>
<tr class="odd">
          <td><code>banner</code></td>
          <td>string</td>
          <td>no</td>
          <td>The server banner, f.x. <code>Apache HTTP Server/2.4.3 openssl/0.9.8c</code></td>
        </tr>
<tr>
          <td><code>basic_auth_pw</code></td>
          <td>string</td>
          <td>no</td>
          <td>The basic auth password sent with this request, if any</td>
        </tr>
<tr class="odd">
          <td><code>canonical_filename</code></td>
          <td>string</td>
          <td>no</td>
          <td>The canonical filename of the request</td>
        </tr>
<tr>
          <td><code>content_encoding</code></td>
          <td>string</td>
          <td>no</td>
          <td>The content encoding of the current request</td>
        </tr>
<tr class="odd">
          <td><code>content_type</code></td>
          <td>string</td>
          <td>yes</td>
          <td>The content type of the current request, as determined in the 
            type_check phase (f.x. <code>image/gif</code> or <code>text/html</code>)</td>
        </tr>
<tr>
          <td><code>context_prefix</code></td>
          <td>string</td>
          <td>no</td>
          <td />
        </tr>
<tr class="odd">
          <td><code>context_document_root</code></td>
          <td>string</td>
          <td>no</td>
          <td />
        </tr>
<tr>
          <td><code>document_root</code></td>
          <td>string</td>
          <td>no</td>
          <td>The document root of the host</td>
        </tr>
<tr class="odd">
          <td><code>err_headers_out</code></td>
          <td>table</td>
          <td>no</td>
          <td>MIME header environment for the response, printed even on errors and
            persist across internal redirects.  A read-only lua table suitable for iteration is available as r:err_headers_out_table().</td>
        </tr>
<tr>
          <td><code>filename</code></td>
          <td>string</td>
          <td>yes</td>
          <td>The file name that the request maps to, f.x. /www/example.com/foo.txt. This can be 
            changed in the pre-translate-name, translate-name or map-to-storage phases of a request to allow the
            default handler (or script handlers) to serve a different file than what was requested.</td>
        </tr>
<tr class="odd">
          <td><code>handler</code></td>
          <td>string</td>
          <td>yes</td>
          <td>The name of the <a href="../handler.html">handler</a> that should serve this request, f.x. 
            <code>lua-script</code> if it is to be served by mod_lua. This is typically set by the 
            <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code> or <code class="directive"><a href="../mod/core.html#sethandler">SetHandler</a></code> 
            directives, but could also be set via mod_lua to allow another handler to serve up a specific request 
            that would otherwise not be served by it.
            </td>
        </tr>
<tr>
          <td><code>headers_in</code></td>
          <td>table</td>
          <td>yes</td>
          <td>MIME header environment from the request. This contains headers such as <code>Host, 
            User-Agent, Referer</code> and so on. A read-only lua table suitable for iteration is available as r:headers_in_table().</td>
        </tr>
<tr class="odd">
          <td><code>headers_out</code></td>
          <td>table</td>
          <td>yes</td>
          <td>MIME header environment for the response. A read-only lua table suitable for iteration is available as r:headers_out_table().</td>
        </tr>
<tr>
          <td><code>hostname</code></td>
          <td>string</td>
          <td>no</td>
          <td>The host name, as set by the <code>Host:</code> header or by a full URI.</td>
        </tr>
<tr class="odd">
          <td><code>is_https</code></td>
          <td>boolean</td>
          <td>no</td>
          <td>Whether or not this request is done via HTTPS</td>
        </tr>
<tr>
          <td><code>is_initial_req</code></td>
          <td>boolean</td>
          <td>no</td>
          <td>Whether this request is the initial request or a sub-request</td>
        </tr>
<tr class="odd">
          <td><code>limit_req_body</code></td>
          <td>number</td>
          <td>no</td>
          <td>The size limit of the request body for this request, or 0 if no limit.</td>
        </tr>
<tr>
          <td><code>log_id</code></td>
          <td>string</td>
          <td>no</td>
          <td>The ID to identify request in access and error log.</td>
        </tr>
<tr class="odd">
          <td><code>method</code></td>
          <td>string</td>
          <td>no</td>
          <td>The request method, f.x. <code>GET</code> or <code>POST</code>.</td>
        </tr>
<tr>
          <td><code>notes</code></td>
          <td>table</td>
          <td>yes</td>
          <td>A list of notes that can be passed on from one module to another.  A read-only lua table suitable for iteration is available as r:notes_table().</td>
        </tr>
<tr class="odd">
          <td><code>options</code></td>
          <td>string</td>
          <td>no</td>
          <td>The Options directive applied to the current request.</td>
        </tr>
<tr>
          <td><code>path_info</code></td>
          <td>string</td>
          <td>no</td>
          <td>The PATH_INFO extracted from this request.</td>
        </tr>
<tr class="odd">
          <td><code>port</code></td>
          <td>number</td>
          <td>no</td>
          <td>The server port used by the request.</td>
        </tr>
<tr>
          <td><code>protocol</code></td>
          <td>string</td>
          <td>no</td>
          <td>The protocol used, f.x. <code>HTTP/1.1</code></td>
        </tr>
<tr class="odd">
          <td><code>proxyreq</code></td>
          <td>string</td>
          <td>yes</td>
          <td>Denotes whether this is a proxy request or not. This value is generally set in 
            the post_read_request/pre_translate_name/translate_name phase of a request.</td>
        </tr>
<tr>
          <td><code>range</code></td>
          <td>string</td>
          <td>no</td>
          <td>The contents of the <code>Range:</code> header.</td>
        </tr>
<tr class="odd">
          <td><code>remaining</code></td>
          <td>number</td>
          <td>no</td>
          <td>The number of bytes remaining to be read from the request body.</td>
        </tr>
<tr>
          <td><code>server_built</code></td>
          <td>string</td>
          <td>no</td>
          <td>The time the server executable was built.</td>
        </tr>
<tr class="odd">
          <td><code>server_name</code></td>
          <td>string</td>
          <td>no</td>
          <td>The server name for this request.</td>
        </tr>
<tr>
          <td><code>some_auth_required</code></td>
          <td>boolean</td>
          <td>no</td>
          <td>Whether some authorization is/was required for this request.</td>
        </tr>
<tr class="odd">
          <td><code>subprocess_env</code></td>
          <td>table</td>
          <td>yes</td>
          <td>The environment variables set for this request. A read-only lua table suitable for iteration is available as r:subprocess_env_table().</td>
        </tr>
<tr>
          <td><code>started</code></td>
          <td>number</td>
          <td>no</td>
          <td>The time the server was (re)started, in seconds since the epoch (Jan 1st, 1970)</td>
        </tr>
<tr class="odd">
          <td><code>status</code></td>
          <td>number</td>
          <td>yes</td>
          <td>The (current) HTTP return code for this request, f.x. <code>200</code> or <code>404</code>.</td>
        </tr>
<tr>
          <td><code>the_request</code></td>
          <td>string</td>
          <td>no</td>
          <td>The request string as sent by the client, f.x. <code>GET /foo/bar HTTP/1.1</code>.</td>
        </tr>
<tr class="odd">
          <td><code>unparsed_uri</code></td>
          <td>string</td>
          <td>no</td>
          <td>The unparsed URI of the request</td>
        </tr>
<tr>
          <td><code>uri</code></td>
          <td>string</td>
          <td>yes</td>
          <td>The URI after it has been parsed by httpd</td>
        </tr>
<tr class="odd">
          <td><code>user</code></td>
          <td>string</td>
          <td>yes</td>
          <td>If an authentication check has been made, this is set to the name of the authenticated user.</td>
        </tr>
<tr>
          <td><code>useragent_ip</code></td>
          <td>string</td>
          <td>no</td>
          <td>The IP of the user agent making the request</td>
        </tr>
</table>
           </dd>
    </dl>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="functions" id="functions">Built in functions</a></h2>

<p>The request_rec object has (at least) the following methods:</p>

<pre class="prettyprint lang-lua">r:flush()   -- flushes the output buffer.
            -- Returns true if the flush was successful, false otherwise.

while we_have_stuff_to_send do
    r:puts("Bla bla bla\n") -- print something to client
    r:flush() -- flush the buffer (send to client)
    r.usleep(500000) -- fake processing time for 0.5 sec. and repeat
end</pre>


<pre class="prettyprint lang-lua">r:add_output_filter(filter_name) -- add an output filter:

r:add_output_filter("fooFilter") -- add the fooFilter to the output stream</pre>


<pre class="prettyprint lang-lua">r:sendfile(filename) -- sends an entire file to the client, using sendfile if supported by the current platform:

if use_sendfile_thing then
    r:sendfile("/var/www/large_file.img")
end</pre>


<pre class="prettyprint lang-lua">r:parseargs() -- returns two tables; one standard key/value table for regular GET data, 
              -- and one for multi-value data (fx. foo=1&amp;foo=2&amp;foo=3):

local GET, GETMULTI = r:parseargs()
r:puts("Your name is: " .. GET['name'] or "Unknown")</pre>


<pre class="prettyprint lang-lua">r:parsebody([sizeLimit]) -- parse the request body as a POST and return two lua tables,
                         -- just like r:parseargs().
                         -- An optional number may be passed to specify the maximum number 
                         -- of bytes to parse. Default is 8192 bytes:
                 
local POST, POSTMULTI = r:parsebody(1024*1024)
r:puts("Your name is: " .. POST['name'] or "Unknown")</pre>


<pre class="prettyprint lang-lua">r:puts("hello", " world", "!") -- print to response body, self explanatory</pre>


<pre class="prettyprint lang-lua">r:write("a single string") -- print to response body, self explanatory</pre>


<pre class="prettyprint lang-lua">r:escape_html("&lt;html&gt;test&lt;/html&gt;") -- Escapes HTML code and returns the escaped result</pre>


<pre class="prettyprint lang-lua">r:base64_encode(string) -- Encodes a string using the Base64 encoding standard:

local encoded = r:base64_encode("This is a test") -- returns VGhpcyBpcyBhIHRlc3Q=</pre>


<pre class="prettyprint lang-lua">r:base64_decode(string) -- Decodes a Base64-encoded string:

local decoded = r:base64_decode("VGhpcyBpcyBhIHRlc3Q=") -- returns 'This is a test'</pre>


<pre class="prettyprint lang-lua">r:md5(string) -- Calculates and returns the MD5 digest of a string (binary safe):

local hash = r:md5("This is a test") -- returns ce114e4501d2f4e2dcea3e17b546f339</pre>


<pre class="prettyprint lang-lua">r:sha1(string) -- Calculates and returns the SHA1 digest of a string (binary safe):

local hash = r:sha1("This is a test") -- returns a54d88e06612d820bc3be72877c74f257b561b19</pre>


<pre class="prettyprint lang-lua">r:escape(string) -- URL-Escapes a string:

local url = "http://foo.bar/1 2 3 &amp; 4 + 5"
local escaped = r:escape(url) -- returns 'http%3a%2f%2ffoo.bar%2f1+2+3+%26+4+%2b+5'</pre>


<pre class="prettyprint lang-lua">r:unescape(string) -- Unescapes an URL-escaped string:

local url = "http%3a%2f%2ffoo.bar%2f1+2+3+%26+4+%2b+5"
local unescaped = r:unescape(url) -- returns 'http://foo.bar/1 2 3 &amp; 4 + 5'</pre>


<pre class="prettyprint lang-lua">r:construct_url(string) -- Constructs an URL from an URI

local url = r:construct_url(r.uri)</pre>


<pre class="prettyprint lang-lua">r.mpm_query(number) -- Queries the server for MPM information using ap_mpm_query:

local mpm = r.mpm_query(14)
if mpm == 1 then
    r:puts("This server uses the Event MPM")
end</pre>


<pre class="prettyprint lang-lua">r:expr(string) -- Evaluates an <a href="../expr.html">expr</a> string.

if r:expr("%{HTTP_HOST} =~ /^www/") then
    r:puts("This host name starts with www")
end</pre>


<pre class="prettyprint lang-lua">r:scoreboard_process(a) -- Queries the server for information about the process at position <code>a</code>:

local process = r:scoreboard_process(1)
r:puts("Server 1 has PID " .. process.pid)</pre>


<pre class="prettyprint lang-lua">r:scoreboard_worker(a, b) -- Queries for information about the worker thread, <code>b</code>, in process <code>a</code>:

local thread = r:scoreboard_worker(1, 1)
r:puts("Server 1's thread 1 has thread ID " .. thread.tid .. " and is in " .. thread.status .. " status")</pre>



<pre class="prettyprint lang-lua">r:clock() -- Returns the current time with microsecond precision</pre>


<pre class="prettyprint lang-lua">r:requestbody(filename) -- Reads and returns the request body of a request.
                -- If 'filename' is specified, it instead saves the
                -- contents to that file:
                
local input = r:requestbody()
r:puts("You sent the following request body to me:\n")
r:puts(input)</pre>


<pre class="prettyprint lang-lua">r:add_input_filter(filter_name) -- Adds 'filter_name' as an input filter</pre>


<pre class="prettyprint lang-lua">r.module_info(module_name) -- Queries the server for information about a module

local mod = r.module_info("mod_lua.c")
if mod then
    for k, v in pairs(mod.commands) do
       r:puts( ("%s: %s\n"):format(k,v)) -- print out all directives accepted by this module
    end
end</pre>


<pre class="prettyprint lang-lua">r:loaded_modules() -- Returns a list of modules loaded by httpd:

for k, module in pairs(r:loaded_modules()) do
    r:puts("I have loaded module " .. module .. "\n")
end</pre>


<pre class="prettyprint lang-lua">r:runtime_dir_relative(filename) -- Compute the name of a run-time file (e.g., shared memory "file") 
                         -- relative to the appropriate run-time directory.</pre>


<pre class="prettyprint lang-lua">r:server_info() -- Returns a table containing server information, such as 
                -- the name of the httpd executable file, mpm used etc.</pre>


<pre class="prettyprint lang-lua">r:set_document_root(file_path) -- Sets the document root for the request to file_path</pre>




<pre class="prettyprint lang-lua">r:set_context_info(prefix, docroot) -- Sets the context prefix and context document root for a request</pre>


<pre class="prettyprint lang-lua">r:os_escape_path(file_path) -- Converts an OS path to a URL in an OS dependent way</pre>


<pre class="prettyprint lang-lua">r:escape_logitem(string) -- Escapes a string for logging</pre>


<pre class="prettyprint lang-lua">r.strcmp_match(string, pattern) -- Checks if 'string' matches 'pattern' using strcmp_match (globs).
                        -- fx. whether 'www.example.com' matches '*.example.com':
                        
local match = r.strcmp_match("foobar.com", "foo*.com")
if match then 
    r:puts("foobar.com matches foo*.com")
end</pre>


<pre class="prettyprint lang-lua">r:set_keepalive() -- Sets the keepalive status for a request. Returns true if possible, false otherwise.</pre>


<pre class="prettyprint lang-lua">r:make_etag() -- Constructs and returns the etag for the current request.</pre>


<pre class="prettyprint lang-lua">r:send_interim_response(clear) -- Sends an interim (1xx) response to the client.
                       -- if 'clear' is true, available headers will be sent and cleared.</pre>


<pre class="prettyprint lang-lua">r:custom_response(status_code, string) -- Construct and set a custom response for a given status code.
                               -- This works much like the ErrorDocument directive:
                               
r:custom_response(404, "Baleted!")</pre>


<pre class="prettyprint lang-lua">r.exists_config_define(string) -- Checks whether a configuration definition exists or not:

if r.exists_config_define("FOO") then
    r:puts("httpd was probably run with -DFOO, or it was defined in the configuration")
end</pre>


<pre class="prettyprint lang-lua">r:state_query(string) -- Queries the server for state information</pre>


<pre class="prettyprint lang-lua">r:stat(filename [,wanted]) -- Runs stat() on a file, and returns a table with file information:

local info = r:stat("/var/www/foo.txt")
if info then
    r:puts("This file exists and was last modified at: " .. info.modified)
end</pre>


<pre class="prettyprint lang-lua">r:regex(string, pattern [,flags]) -- Runs a regular expression match on a string, returning captures if matched:

local matches = r:regex("foo bar baz", [[foo (\w+) (\S*)]])
if matches then
    r:puts("The regex matched, and the last word captured ($2) was: " .. matches[2])
end

-- Example ignoring case sensitivity:
local matches = r:regex("FOO bar BAz", [[(foo) bar]], 1)

-- Flags can be a bitwise combination of:
-- 0x01: Ignore case
-- 0x02: Multiline search</pre>


<pre class="prettyprint lang-lua">r.usleep(number_of_microseconds) -- Puts the script to sleep for a given number of microseconds.</pre>


<pre class="prettyprint lang-lua">r:dbacquire(dbType[, dbParams]) -- Acquires a connection to a database and returns a database class.
                        -- See '<a href="#databases">Database connectivity</a>' for details.</pre>


<pre class="prettyprint lang-lua">r:ivm_set("key", value) -- Set an Inter-VM variable to hold a specific value.
                        -- These values persist even though the VM is gone or not being used,
                        -- and so should only be used if MaxConnectionsPerChild is &gt; 0
                        -- Values can be numbers, strings and booleans, and are stored on a 
                        -- per process basis (so they won't do much good with a prefork mpm)
                        
r:ivm_get("key")        -- Fetches a variable set by ivm_set. Returns the contents of the variable
                        -- if it exists or nil if no such variable exists.
                        
-- An example getter/setter that saves a global variable outside the VM:
function handle(r)
    -- First VM to call this will get no value, and will have to create it
    local foo = r:ivm_get("cached_data")
    if not foo then
        foo = do_some_calcs() -- fake some return value
        r:ivm_set("cached_data", foo) -- set it globally
    end
    r:puts("Cached data is: ", foo)
end</pre>


<pre class="prettyprint lang-lua">r:htpassword(string [,algorithm [,cost]]) -- Creates a password hash from a string.
                                          -- algorithm: 0 = APMD5 (default), 1 = SHA, 2 = BCRYPT, 3 = CRYPT.
                                          -- cost: only valid with BCRYPT algorithm (default = 5).</pre>


<pre class="prettyprint lang-lua">r:mkdir(dir [,mode]) -- Creates a directory and sets mode to optional mode parameter.</pre>


<pre class="prettyprint lang-lua">r:mkrdir(dir [,mode]) -- Creates directories recursive and sets mode to optional mode parameter.</pre>


<pre class="prettyprint lang-lua">r:rmdir(dir) -- Removes a directory.</pre>


<pre class="prettyprint lang-lua">r:touch(file [,mtime]) -- Sets the file modification time to current time or to optional mtime msec value.</pre>


<pre class="prettyprint lang-lua">r:get_direntries(dir) -- Returns a table with all directory entries.

function handle(r)
  local dir = r.context_document_root
  for _, f in ipairs(r:get_direntries(dir)) do
    local info = r:stat(dir .. "/" .. f)
    if info then
      local mtime = os.date(fmt, info.mtime / 1000000)
      local ftype = (info.filetype == 2) and "[dir] " or "[file]"
      r:puts( ("%s %s %10i %s\n"):format(ftype, mtime, info.size, f) )
    end
  end
end</pre>


<pre class="prettyprint lang-lua">r.date_parse_rfc(string) -- Parses a date/time string and returns seconds since epoche.</pre>


<pre class="prettyprint lang-lua">r:getcookie(key) -- Gets a HTTP cookie</pre>


<pre class="prettyprint lang-lua">r:setcookie{
  key = [key],
  value = [value],
  expires = [expiry],
  secure = [boolean],
  httponly = [boolean],
  path = [path],
  domain = [domain]
} -- Sets a HTTP cookie, for instance:

r:setcookie{
  key = "cookie1",
  value = "HDHfa9eyffh396rt",
  expires = os.time() + 86400,
  secure = true
}</pre>


<pre class="prettyprint lang-lua">r:wsupgrade() -- Upgrades a connection to WebSockets if possible (and requested):
if r:wsupgrade() then -- if we can upgrade:
    r:wswrite("Welcome to websockets!") -- write something to the client
    r:wsclose()  -- goodbye!
end</pre>


<pre class="prettyprint lang-lua">r:wsread() -- Reads a WebSocket frame from a WebSocket upgraded connection (see above):

local line, isFinal = r:wsread() -- isFinal denotes whether this is the final frame.
                                 -- If it isn't, then more frames can be read
r:wswrite("You wrote: " .. line)</pre>


<pre class="prettyprint lang-lua">r:wswrite(line) -- Writes a frame to a WebSocket client:
r:wswrite("Hello, world!")</pre>


<pre class="prettyprint lang-lua">r:wsclose() -- Closes a WebSocket request and terminates it for httpd:

if r:wsupgrade() then
    r:wswrite("Write something: ")
    local line = r:wsread() or "nothing"
    r:wswrite("You wrote: " .. line);
    r:wswrite("Goodbye!")
    r:wsclose()
end</pre>


</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="logging" id="logging">Logging Functions</a></h2>

<pre class="prettyprint lang-lua">-- examples of logging messages
r:trace1("This is a trace log message") -- trace1 through trace8 can be used
r:debug("This is a debug log message")
r:info("This is an info log message")
r:notice("This is a notice log message")
r:warn("This is a warn log message")
r:err("This is an err log message")
r:alert("This is an alert log message")
r:crit("This is a crit log message")
r:emerg("This is an emerg log message")</pre>


</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="apache2" id="apache2">apache2 Package</a></h2>
<p>A package named <code>apache2</code> is available with (at least) the following contents.</p>
<dl>
  <dt>apache2.OK</dt>
  <dd>internal constant OK.  Handlers should return this if they've
  handled the request.</dd>
  <dt>apache2.DECLINED</dt>
  <dd>internal constant DECLINED.  Handlers should return this if
  they are not going to handle the request.</dd>
  <dt>apache2.DONE</dt>
  <dd>internal constant DONE.</dd>
  <dt>apache2.version</dt>
  <dd>Apache HTTP server version string</dd>
  <dt>apache2.HTTP_MOVED_TEMPORARILY</dt>
  <dd>HTTP status code</dd>
  <dt>apache2.PROXYREQ_NONE, apache2.PROXYREQ_PROXY, apache2.PROXYREQ_REVERSE, apache2.PROXYREQ_RESPONSE</dt>
  <dd>internal constants used by <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code></dd>
  <dt>apache2.AUTHZ_DENIED, apache2.AUTHZ_GRANTED, apache2.AUTHZ_NEUTRAL, apache2.AUTHZ_GENERAL_ERROR, apache2.AUTHZ_DENIED_NO_USER</dt>
  <dd>internal constants used by <code class="module"><a href="../mod/mod_authz_core.html">mod_authz_core</a></code></dd>

</dl>
<p>(Other HTTP status codes are not yet implemented.)</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="modifying_buckets" id="modifying_buckets">Modifying contents with Lua filters</a></h2>
    
    <p>
    Filter functions implemented via <code class="directive"><a href="#luainputfilter">LuaInputFilter</a></code> 
    or <code class="directive"><a href="#luaoutputfilter">LuaOutputFilter</a></code> are designed as 
    three-stage non-blocking functions using coroutines to suspend and resume a 
    function as buckets are sent down the filter chain. The core structure of 
    such a function is:
    </p>
    <pre class="prettyprint lang-lua">function filter(r)
    -- Our first yield is to signal that we are ready to receive buckets.
    -- Before this yield, we can set up our environment, check for conditions,
    -- and, if we deem it necessary, decline filtering a request altogether:
    if something_bad then
        return -- This would skip this filter.
    end
    -- Regardless of whether we have data to prepend, a yield MUST be called here.
    -- Note that only output filters can prepend data. Input filters must use the 
    -- final stage to append data to the content.
    coroutine.yield([optional header to be prepended to the content])
    
    -- After we have yielded, buckets will be sent to us, one by one, and we can 
    -- do whatever we want with them and then pass on the result.
    -- Buckets are stored in the global variable 'bucket', so we create a loop
    -- that checks if 'bucket' is not nil:
    while bucket ~= nil do
        local output = mangle(bucket) -- Do some stuff to the content
        coroutine.yield(output) -- Return our new content to the filter chain
    end

    -- Once the buckets are gone, 'bucket' is set to nil, which will exit the 
    -- loop and land us here. Anything extra we want to append to the content
    -- can be done by doing a final yield here. Both input and output filters 
    -- can append data to the content in this phase.
    coroutine.yield([optional footer to be appended to the content])
end</pre>

</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="databases" id="databases">Database connectivity</a></h2>
    
    <p>
    Mod_lua implements a simple database feature for querying and running commands
    on the most popular database engines (mySQL, PostgreSQL, FreeTDS, ODBC, SQLite, Oracle)
    as well as mod_dbd.</p>
    <p>
    The <code>dbType</code> to use as the first parameter of <code>dbacquire</code>
    is case sensitive.</p>
    <p>
    It should be one of <code>mysql</code>, <code>pgsql</code>, <code>freetds</code>,
    <code>odbc</code>, <code>sqlite2</code>, <code>sqlite3</code>, <code>oracle</code>
    or <code>mod_dbd</code>.
    </p>
    <p>The example below shows how to acquire a database handle and return information from a table:</p>
    <pre class="prettyprint lang-lua">function handle(r)
    -- Acquire a database handle
    local database, err = r:dbacquire("mysql", "server=localhost,user=someuser,pass=somepass,dbname=mydb")
    if not err then
        -- Select some information from it
        local results, err = database:select(r, "SELECT `name`, `age` FROM `people` WHERE 1")
        if not err then
            local rows = results(0) -- fetch all rows synchronously
            for k, row in pairs(rows) do
                r:puts( string.format("Name: %s, Age: %s&lt;br/&gt;", row[1], row[2]) )
            end
        else
            r:puts("Database query error: " .. err)
        end
        database:close()
    else
        r:puts("Could not connect to the database: " .. err)
    end
end</pre>

    <p>
    To utilize <code class="module"><a href="../mod/mod_dbd.html">mod_dbd</a></code>, specify <code>mod_dbd</code>
    as the database type, or leave the field blank:
    </p>
    <pre class="prettyprint lang-lua">local database = r:dbacquire("mod_dbd")</pre>

    <h3><a name="database_object" id="database_object">Database object and contained functions</a></h3>
        
        <p>The database object returned by <code>dbacquire</code> has the following methods:</p>
        <p><strong>Normal select and query from a database:</strong></p>
    <pre class="prettyprint lang-lua">-- Run a statement and return the number of rows affected:
local affected, errmsg = database:query(r, "DELETE FROM `tbl` WHERE 1")

-- Run a statement and return a result set that can be used synchronously or async:
local result, errmsg = database:select(r, "SELECT * FROM `people` WHERE 1")</pre>

        <p><strong>Using prepared statements (recommended):</strong></p>
    <pre class="prettyprint lang-lua">-- Create and run a prepared statement:
local statement, errmsg = database:prepare(r, "DELETE FROM `tbl` WHERE `age` &gt; %u")
if not errmsg then
    local result, errmsg = statement:query(20) -- run the statement with age &gt; 20
end

-- Fetch a prepared statement from a DBDPrepareSQL directive:
local statement, errmsg = database:prepared(r, "someTag")
if not errmsg then
    local result, errmsg = statement:select("John Doe", 123) -- inject the values "John Doe" and 123 into the statement
end</pre>

        <p><strong>Escaping values, closing databases etc:</strong></p>
    <pre class="prettyprint lang-lua">-- Escape a value for use in a statement:
local escaped = database:escape(r, [["'|blabla]])

-- Close a database connection and free up handles:
database:close()

-- Check whether a database connection is up and running:
local connected = database:active()</pre>

    
    <h3><a name="result_sets" id="result_sets">Working with result sets</a></h3>
    
    <p>The result set returned by <code>db:select</code> or by the prepared statement functions 
    created through <code>db:prepare</code> can be used to
    fetch rows synchronously or asynchronously, depending on the row number specified:<br />
    <code>result(0)</code> fetches all rows in a synchronous manner, returning a table of rows.<br />
    <code>result(-1)</code> fetches the next available row in the set, asynchronously.<br />
    <code>result(N)</code> fetches row number <code>N</code>, asynchronously:
    </p>
    <pre class="prettyprint lang-lua">-- fetch a result set using a regular query:
local result, err = db:select(r, "SELECT * FROM `tbl` WHERE 1")

local rows = result(0) -- Fetch ALL rows synchronously
local row = result(-1) -- Fetch the next available row, asynchronously
local row = result(1234) -- Fetch row number 1234, asynchronously
local row = result(-1, true) -- Fetch the next available row, using row names as key indexes.</pre>

    <p>One can construct a function that returns an iterative function to iterate over all rows 
    in a synchronous or asynchronous way, depending on the async argument:
    </p>
    <pre class="prettyprint lang-lua">function rows(resultset, async)
    local a = 0
    local function getnext()
        a = a + 1
        local row = resultset(-1)
        return row and a or nil, row
    end
    if not async then
        return pairs(resultset(0))
    else
        return getnext, self
    end
end

local statement, err = db:prepare(r, "SELECT * FROM `tbl` WHERE `age` &gt; %u")
if not err then
     -- fetch rows asynchronously:
    local result, err = statement:select(20)
    if not err then
        for index, row in rows(result, true) do
            ....
        end
    end

     -- fetch rows synchronously:
    local result, err = statement:select(20)
    if not err then
        for index, row in rows(result, false) do
            ....
        end
    end
end</pre>

    
    <h3><a name="closing_databases" id="closing_databases">Closing a database connection</a></h3>
        

    <p>Database handles should be closed using <code>database:close()</code> when they are no longer
    needed. If you do not close them manually, they will eventually be garbage collected and 
    closed by mod_lua, but you may end up having too many unused connections to the database 
    if you leave the closing up to mod_lua. Essentially, the following two measures are
    the same:
    </p>
    <pre class="prettyprint lang-lua">-- Method 1: Manually close a handle
local database = r:dbacquire("mod_dbd")
database:close() -- All done

-- Method 2: Letting the garbage collector close it
local database = r:dbacquire("mod_dbd")
database = nil -- throw away the reference
collectgarbage() -- close the handle via GC</pre>

    
    <h3><a name="database_caveat" id="database_caveat">Precautions when working with databases</a></h3>
    
    <p>Although the standard <code>query</code> and <code>run</code> functions are freely 
    available, it is recommended that you use prepared statements whenever possible, to 
    both optimize performance (if your db handle lives on for a long time) and to minimize 
    the risk of SQL injection attacks. <code>run</code> and <code>query</code> should only
    be used when there are no variables inserted into a statement (a static statement). 
    When using dynamic statements, use <code>db:prepare</code> or <code>db:prepared</code>.
    </p>
    

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaAuthzProvider" id="LuaAuthzProvider">LuaAuthzProvider</a> <a name="luaauthzprovider" id="luaauthzprovider">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Plug an authorization provider function into <code class="module"><a href="../mod/mod_authz_core.html">mod_authz_core</a></code>
</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaAuthzProvider provider_name /path/to/lua/script.lua function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.4.3 and later</td></tr>
</table>
<p>After a lua function has been registered as authorization provider, it can be used
with the <code class="directive"><a href="../mod/mod_authz_core.html#require">Require</a></code> directive:</p>

<pre class="prettyprint lang-config">LuaRoot "/usr/local/apache2/lua"
LuaAuthzProvider foo authz.lua authz_check_foo
&lt;Location "/"&gt;
  Require foo johndoe
&lt;/Location&gt;</pre>

<pre class="prettyprint lang-lua">require "apache2"
function authz_check_foo(r, who)
    if r.user ~= who then return apache2.AUTHZ_DENIED
    return apache2.AUTHZ_GRANTED
end</pre>




</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaCodeCache" id="LuaCodeCache">LuaCodeCache</a> <a name="luacodecache" id="luacodecache">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configure the compiled code cache.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaCodeCache stat|forever|never</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaCodeCache stat</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table><p>
    Specify the behavior of the in-memory code cache. The default
    is stat, which stats the top level script (not any included
    ones) each time that file is needed, and reloads it if the
    modified time indicates it is newer than the one it has
    already loaded. The other values cause it to keep the file
    cached forever (don't stat and replace) or to never cache the
    file.</p>

    <p>In general stat or forever is good for production, and stat or never
    for development.</p>

    <div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">LuaCodeCache stat
LuaCodeCache forever
LuaCodeCache never</pre>
</div>


</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookAccessChecker" id="LuaHookAccessChecker">LuaHookAccessChecker</a> <a name="luahookaccesschecker" id="luahookaccesschecker">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the access_checker phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookAccessChecker  /path/to/lua/script.lua  hook_function_name [early|late]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The optional third argument is supported in 2.3.15 and later</td></tr>
</table>
<p>Add your hook to the access_checker phase.  An access checker
hook function usually returns OK, DECLINED, or HTTP_FORBIDDEN.</p>
   <div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late" 
   control when this script runs relative to other modules.</p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookAuthChecker" id="LuaHookAuthChecker">LuaHookAuthChecker</a> <a name="luahookauthchecker" id="luahookauthchecker">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the auth_checker phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookAuthChecker  /path/to/lua/script.lua hook_function_name [early|late]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The optional third argument is supported in 2.3.15 and later</td></tr>
</table>
<p>Invoke a lua function in the auth_checker phase of processing
a request.  This can be used to implement arbitrary authentication
and authorization checking.  A very simple example:
</p>
<pre class="prettyprint lang-lua">require 'apache2'

-- fake authcheck hook
-- If request has no auth info, set the response header and
-- return a 401 to ask the browser for basic auth info.
-- If request has auth info, don't actually look at it, just
-- pretend we got userid 'foo' and validated it.
-- Then check if the userid is 'foo' and accept the request.
function authcheck_hook(r)

   -- look for auth info
   auth = r.headers_in['Authorization']
   if auth ~= nil then
     -- fake the user
     r.user = 'foo'
   end

   if r.user == nil then
      r:debug("authcheck: user is nil, returning 401")
      r.err_headers_out['WWW-Authenticate'] = 'Basic realm="WallyWorld"'
      return 401
   elseif r.user == "foo" then
      r:debug('user foo: OK')
   else
      r:debug("authcheck: user='" .. r.user .. "'")
      r.err_headers_out['WWW-Authenticate'] = 'Basic realm="WallyWorld"'
      return 401
   end
   return apache2.OK
end</pre>

   <div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late" 
   control when this script runs relative to other modules.</p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookCheckUserID" id="LuaHookCheckUserID">LuaHookCheckUserID</a> <a name="luahookcheckuserid" id="luahookcheckuserid">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the check_user_id phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookCheckUserID  /path/to/lua/script.lua hook_function_name [early|late]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The optional third argument is supported in 2.3.15 and later</td></tr>
</table><p>...</p>
   <div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late" 
   control when this script runs relative to other modules.</p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookFixups" id="LuaHookFixups">LuaHookFixups</a> <a name="luahookfixups" id="luahookfixups">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the fixups phase of a request
processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookFixups  /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
<p>
    Just like LuaHookTranslateName, but executed at the fixups phase
</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookInsertFilter" id="LuaHookInsertFilter">LuaHookInsertFilter</a> <a name="luahookinsertfilter" id="luahookinsertfilter">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the insert_filter phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookInsertFilter  /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table><p>Not Yet Implemented</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookLog" id="LuaHookLog">LuaHookLog</a> <a name="luahooklog" id="luahooklog">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the access log phase of a request
processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookLog  /path/to/lua/script.lua log_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
<p>
    This simple logging hook allows you to run a function when httpd enters the 
    logging phase of a request. With it, you can append data to your own logs, 
    manipulate data before the regular log is written, or prevent a log entry 
    from being created. To prevent the usual logging from happening, simply return
    <code>apache2.DONE</code> in your logging handler, otherwise return 
    <code>apache2.OK</code> to tell httpd to log as normal.
</p>
<p>Example:</p>
<pre class="prettyprint lang-config">LuaHookLog "/path/to/script.lua" logger</pre>

<pre class="prettyprint lang-lua">-- /path/to/script.lua --
function logger(r)
    -- flip a coin:
    -- If 1, then we write to our own Lua log and tell httpd not to log
    -- in the main log.
    -- If 2, then we just sanitize the output a bit and tell httpd to 
    -- log the sanitized bits.

    if math.random(1,2) == 1 then
        -- Log stuff ourselves and don't log in the regular log
        local f = io.open("/foo/secret.log", "a")
        if f then
            f:write("Something secret happened at " .. r.uri .. "\n")
            f:close()
        end
        return apache2.DONE -- Tell httpd not to use the regular logging functions
    else
        r.uri = r.uri:gsub("somesecretstuff", "") -- sanitize the URI
        return apache2.OK -- tell httpd to log it.
    end
end</pre>


</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookMapToStorage" id="LuaHookMapToStorage">LuaHookMapToStorage</a> <a name="luahookmaptostorage" id="luahookmaptostorage">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the map_to_storage phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookMapToStorage  /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
    <p>Like <code class="directive">LuaHookTranslateName</code> but executed at the 
    map-to-storage phase of a request. Modules like <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> run at this phase,
    which makes for an interesting example on what to do here:</p>
    <pre class="prettyprint lang-config">LuaHookMapToStorage "/path/to/lua/script.lua" check_cache</pre>

    <pre class="prettyprint lang-lua">require"apache2"
cached_files = {}

function read_file(filename) 
    local input = io.open(filename, "r")
    if input then
        local data = input:read("*a")
        cached_files[filename] = data
        file = cached_files[filename]
        input:close()
    end
    return cached_files[filename]
end

function check_cache(r)
    if r.filename:match("%.png$") then -- Only match PNG files
        local file = cached_files[r.filename] -- Check cache entries
        if not file then
            file = read_file(r.filename)  -- Read file into cache
        end
        if file then -- If file exists, write it out
            r.status = 200
            r:write(file)
            r:info(("Sent %s to client from cache"):format(r.filename))
            return apache2.DONE -- skip default handler for PNG files
        end
    end
    return apache2.DECLINED -- If we had nothing to do, let others serve this.
end</pre>


    
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookPreTranslate" id="LuaHookPreTranslate">LuaHookPreTranslate</a> <a name="luahookpretranslate" id="luahookpretranslate">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the pre_translate phase of a request
processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookPreTranslate  /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
<p>
    Just like LuaHookTranslateName, but executed at the pre_translate phase,
    where the URI-path is not percent decoded.
</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookTranslateName" id="LuaHookTranslateName">LuaHookTranslateName</a> <a name="luahooktranslatename" id="luahooktranslatename">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the translate name phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookTranslateName  /path/to/lua/script.lua  hook_function_name [early|late]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The optional third argument is supported in 2.3.15 and later</td></tr>
</table><p>
    Add a hook (at APR_HOOK_MIDDLE) to the translate name phase of
    request processing. The hook function receives a single
    argument, the request_rec, and should return a status code,
    which is either an HTTP error code, or the constants defined
    in the apache2 module: apache2.OK, apache2.DECLINED, or
    apache2.DONE. </p>

    <p>For those new to hooks, basically each hook will be invoked
    until one of them returns apache2.OK. If your hook doesn't
    want to do the translation it should just return
    apache2.DECLINED. If the request should stop processing, then
    return apache2.DONE.</p>

    <p>Example:</p>

<pre class="prettyprint lang-config"># httpd.conf
LuaHookTranslateName "/scripts/conf/hooks.lua" silly_mapper</pre>


<pre class="prettyprint lang-lua">-- /scripts/conf/hooks.lua --
require "apache2"
function silly_mapper(r)
    if r.uri == "/" then
        r.filename = "/var/www/home.lua"
        return apache2.OK
    else
        return apache2.DECLINED
    end
end</pre>


   <div class="note"><h3>Context</h3><p>This directive is not valid in <code class="directive"><a href="../mod/core.html#directory">&lt;Directory&gt;</a></code>, <code class="directive"><a href="../mod/core.html#files">&lt;Files&gt;</a></code>, or htaccess
   context.</p></div>

   <div class="note"><h3>Ordering</h3><p>The optional arguments "early" or "late" 
   control when this script runs relative to other modules.</p></div>


</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaHookTypeChecker" id="LuaHookTypeChecker">LuaHookTypeChecker</a> <a name="luahooktypechecker" id="luahooktypechecker">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the type_checker phase of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaHookTypeChecker  /path/to/lua/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table><p>
    This directive provides a hook for the type_checker phase of the request processing. 
    This phase is where requests are assigned a content type and a handler, and thus can 
    be used to modify the type and handler based on input:
    </p>
    <pre class="prettyprint lang-config">LuaHookTypeChecker "/path/to/lua/script.lua" type_checker</pre>

    <pre class="prettyprint lang-lua">    function type_checker(r)
        if r.uri:match("%.to_gif$") then -- match foo.png.to_gif
            r.content_type = "image/gif" -- assign it the image/gif type
            r.handler = "gifWizard"      -- tell the gifWizard module to handle this
            r.filename = r.uri:gsub("%.to_gif$", "") -- fix the filename requested
            return apache2.OK
        end

        return apache2.DECLINED
    end</pre>


</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaInherit" id="LuaInherit">LuaInherit</a> <a name="luainherit" id="luainherit">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Controls how parent configuration sections are merged into children</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaInherit none|parent-first|parent-last</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaInherit parent-first</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.4.0 and later</td></tr>
</table><p>By default, if LuaHook* directives are used in overlapping
    Directory or Location configuration sections, the scripts defined in the
    more specific section are run <em>after</em> those defined in the more
    generic section (LuaInherit parent-first).  You can reverse this order, or
    make the parent context not apply at all.</p>
    
    <p> In previous 2.3.x releases, the default was effectively to ignore LuaHook*
    directives from parent configuration sections.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaInputFilter" id="LuaInputFilter">LuaInputFilter</a> <a name="luainputfilter" id="luainputfilter">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a Lua function for content input filtering</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaInputFilter filter_name /path/to/lua/script.lua function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.4.5 and later</td></tr>
</table>
<p>Provides a means of adding a Lua function as an input filter. 
As with output filters, input filters work as coroutines, 
first yielding before buffers are sent, then yielding whenever 
a bucket needs to be passed down the chain, and finally (optionally) 
yielding anything that needs to be appended to the input data. The 
global variable <code>bucket</code> holds the buckets as they are passed 
onto the Lua script:
</p>

<pre class="prettyprint lang-config">LuaInputFilter myInputFilter "/www/filter.lua" input_filter
&lt;Files "*.lua"&gt;
  SetInputFilter myInputFilter
&lt;/Files&gt;</pre>

<pre class="prettyprint lang-lua">--[[
    Example input filter that converts all POST data to uppercase.
]]--
function input_filter(r)
    print("luaInputFilter called") -- debug print
    coroutine.yield() -- Yield and wait for buckets
    while bucket do -- For each bucket, do...
        local output = string.upper(bucket) -- Convert all POST data to uppercase
        coroutine.yield(output) -- Send converted data down the chain
    end
    -- No more buckets available.
    coroutine.yield("&amp;filterSignature=1234") -- Append signature at the end
end</pre>

<p>
The input filter supports denying/skipping a filter if it is deemed unwanted:
</p>
<pre class="prettyprint lang-lua">function input_filter(r)
    if not good then
        return -- Simply deny filtering, passing on the original content instead
    end
    coroutine.yield() -- wait for buckets
    ... -- insert filter stuff here
end</pre>

<p>
See "<a href="#modifying_buckets">Modifying contents with Lua 
filters</a>" for more information.
</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaMapHandler" id="LuaMapHandler">LuaMapHandler</a> <a name="luamaphandler" id="luamaphandler">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Map a path to a lua handler</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaMapHandler uri-pattern /path/to/lua/script.lua [function-name]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
    <p>This directive matches a uri pattern to invoke a specific
    handler function in a specific file. It uses PCRE regular
    expressions to match the uri, and supports interpolating
    match groups into both the file path and the function name. 
    Be careful writing your regular expressions to avoid security
    issues.</p>
   <div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">LuaMapHandler "/(\w+)/(\w+)" "/scripts/$1.lua" "handle_$2"</pre>
</div>
        <p>This would match uri's such as /photos/show?id=9
        to the file /scripts/photos.lua and invoke the
        handler function handle_show on the lua vm after
        loading that file.</p>

<pre class="prettyprint lang-config">LuaMapHandler "/bingo" "/scripts/wombat.lua"</pre>

        <p>This would invoke the "handle" function, which
        is the default if no specific function name is
        provided.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaOutputFilter" id="LuaOutputFilter">LuaOutputFilter</a> <a name="luaoutputfilter" id="luaoutputfilter">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a Lua function for content output filtering</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaOutputFilter filter_name /path/to/lua/script.lua function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>2.4.5 and later</td></tr>
</table>
<p>Provides a means of adding a Lua function as an output filter. 
As with input filters, output filters work as coroutines, 
first yielding before buffers are sent, then yielding whenever 
a bucket needs to be passed down the chain, and finally (optionally) 
yielding anything that needs to be appended to the input data. The 
global variable <code>bucket</code> holds the buckets as they are passed 
onto the Lua script:
</p>

<pre class="prettyprint lang-config">LuaOutputFilter myOutputFilter "/www/filter.lua" output_filter
&lt;Files "*.lua"&gt;
  SetOutputFilter myOutputFilter
&lt;/Files&gt;</pre>

<pre class="prettyprint lang-lua">--[[
    Example output filter that escapes all HTML entities in the output
]]--
function output_filter(r)
    coroutine.yield("(Handled by myOutputFilter)&lt;br/&gt;\n") -- Prepend some data to the output,
                                                          -- yield and wait for buckets.
    while bucket do -- For each bucket, do...
        local output = r:escape_html(bucket) -- Escape all output
        coroutine.yield(output) -- Send converted data down the chain
    end
    -- No more buckets available.
end</pre>

<p>
As with the input filter, the output filter supports denying/skipping a filter 
if it is deemed unwanted:
</p>
<pre class="prettyprint lang-lua">function output_filter(r)
    if not r.content_type:match("text/html") then
        return -- Simply deny filtering, passing on the original content instead
    end
    coroutine.yield() -- wait for buckets
    ... -- insert filter stuff here
end</pre>

<div class="note"><h3>Lua filters with <code class="module"><a href="../mod/mod_filter.html">mod_filter</a></code></h3>
<p> When a Lua filter is used as the underlying provider via the 
<code class="directive"><a href="../mod/mod_filter.html#filterprovider">FilterProvider</a></code> directive, filtering 
will only work when the <var>filter-name</var> is identical to the <var>provider-name</var>.
</p> </div>

<p>
See "<a href="#modifying_buckets">Modifying contents with Lua filters</a>" for more 
information.
</p>


</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaPackageCPath" id="LuaPackageCPath">LuaPackageCPath</a> <a name="luapackagecpath" id="luapackagecpath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Add a directory to lua's package.cpath</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaPackageCPath /path/to/include/?.soa</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
    <p>Add a path to lua's shared library search path. Follows the same
    conventions as lua. This just munges the package.cpath in the
    lua vms.</p>


</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaPackagePath" id="LuaPackagePath">LuaPackagePath</a> <a name="luapackagepath" id="luapackagepath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Add a directory to lua's package.path</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaPackagePath /path/to/include/?.lua</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table><p>Add a path to lua's module search path. Follows the same
    conventions as lua. This just munges the package.path in the
    lua vms.</p>

    <div class="example"><h3>Examples:</h3><pre class="prettyprint lang-config">LuaPackagePath "/scripts/lib/?.lua"
LuaPackagePath "/scripts/lib/?/init.lua"</pre>
</div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaQuickHandler" id="LuaQuickHandler">LuaQuickHandler</a> <a name="luaquickhandler" id="luaquickhandler">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Provide a hook for the quick handler of request processing</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaQuickHandler /path/to/script.lua hook_function_name</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
    <p>
    This phase is run immediately after the request has been mapped to a virtual host, 
    and can be used to either do some request processing before the other phases kick 
    in, or to serve a request without the need to translate, map to storage et cetera. 
    As this phase is run before anything else, directives such as <code class="directive"><a href="../mod/core.html#location">&lt;Location&gt;</a></code> or <code class="directive"><a href="../mod/core.html#directory">&lt;Directory&gt;</a></code> are void in this phase, just as 
    URIs have not been properly parsed yet.
    </p>
   <div class="note"><h3>Context</h3><p>This directive is not valid in <code class="directive"><a href="../mod/core.html#directory">&lt;Directory&gt;</a></code>, <code class="directive"><a href="../mod/core.html#files">&lt;Files&gt;</a></code>, or htaccess
   context.</p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaRoot" id="LuaRoot">LuaRoot</a> <a name="luaroot" id="luaroot">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Specify the base path for resolving relative paths for mod_lua directives</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaRoot /path/to/a/directory</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
    <p>Specify the base path which will be used to evaluate all
    relative paths within mod_lua. If not specified they
    will be resolved relative to the current working directory,
    which may not always work well for a server.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="LuaScope" id="LuaScope">LuaScope</a> <a name="luascope" id="luascope">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>One of once, request, conn, thread -- default is once</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LuaScope once|request|conn|thread|server [min] [max]</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LuaScope once</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>All</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_lua</td></tr>
</table>
    <p>Specify the life cycle scope of the Lua interpreter which will
    be used by handlers in this "Directory." The default is "once"</p>

   <dl>
    <dt>once:</dt> <dd>use the interpreter once and throw it away.</dd>

    <dt>request:</dt> <dd>use the interpreter to handle anything based on
             the same file within this request, which is also
             request scoped.</dd>

    <dt>conn:</dt> <dd>Same as request but attached to the connection_rec</dd>

    <dt>thread:</dt> <dd>Use the interpreter for the lifetime of the thread 
            handling the request (only available with threaded MPMs).</dd>

    <dt>server:</dt>  <dd>This one is different than others because the
            server scope is quite long lived, and multiple threads
            will have the same server_rec. To accommodate this,
            server scoped Lua states are stored in an apr
            resource list. The <code>min</code> and <code>max</code> arguments 
            specify the minimum and maximum number of Lua states to keep in the 
            pool.</dd>
   </dl>
    <p>
    Generally speaking, the <code>thread</code> and <code>server</code> scopes 
    execute roughly 2-3 times faster than the rest, because they don't have to 
    spawn new Lua states on every request (especially with the event MPM, as 
    even keepalive requests will use a new thread for each request). If you are 
    satisfied that your scripts will not have problems reusing a state, then 
    the <code>thread</code> or <code>server</code> scopes should be used for 
    maximum performance. While the <code>thread</code> scope will provide the 
    fastest responses, the <code>server</code> scope will use less memory, as 
    states are pooled, allowing f.x. 1000 threads to share only 100 Lua states, 
    thus using only 10% of the memory required by the <code>thread</code> scope.
    </p>

</div>
</div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="../en/mod/mod_lua.html" title="English">&nbsp;en&nbsp;</a> |
<a href="../fr/mod/mod_lua.html" hreflang="fr" rel="alternate" title="Français">&nbsp;fr&nbsp;</a></p>
</div><div class="top"><a href="#page-header"><img src="../images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&amp;A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Libera.chat, or sent to our <a href="https://httpd.apache.org/lists.html">mailing lists</a>.</div>
<script type="text/javascript"><!--//--><![CDATA[//><!--
var comments_shortname = 'httpd';
var comments_identifier = 'http://httpd.apache.org/docs/2.4/mod/mod_lua.html';
(function(w, d) {
    if (w.location.hostname.toLowerCase() == "httpd.apache.org") {
        d.write('<div id="comments_thread"><\/div>');
        var s = d.createElement('script');
        s.type = 'text/javascript';
        s.async = true;
        s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier;
        (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s);
    }
    else { 
        d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>');
    }
})(window, document);
//--><!]]></script></div><div id="footer">
<p class="apache">Copyright 2023 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div><script type="text/javascript"><!--//--><![CDATA[//><!--
if (typeof(prettyPrint) !== 'undefined') {
    prettyPrint();
}
//--><!]]></script>
</body></html>