From: Nick Kew Date: Tue, 10 Oct 2006 10:33:06 +0000 (+0000) Subject: Add SQL Query capability to RewriteMap X-Git-Tag: 2.3.0~2086 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=0e9e39732f7a94ddb680243dcc60ee9c7289ea2d;p=apache Add SQL Query capability to RewriteMap git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@454683 13f79535-47bb-0310-9956-ffa450edef68 --- diff --git a/CHANGES b/CHANGES index 8e7797f74f..6cc742f404 100644 --- a/CHANGES +++ b/CHANGES @@ -2,6 +2,8 @@ Changes with Apache 2.3.0 [Remove entries to the current 2.0 and 2.2 section below, when backported] + *) mod_rewrite: support rewritemap by SQL query [Nick Kew] + *) Fix issue which could cause piped loggers to be orphaned and never terminate after a graceful restart. PR 40651. [Joe Orton, Ruediger Pluem] diff --git a/docs/manual/mod/mod_rewrite.xml b/docs/manual/mod/mod_rewrite.xml index f8970775a9..a8abddad7b 100644 --- a/docs/manual/mod/mod_rewrite.xml +++ b/docs/manual/mod/mod_rewrite.xml @@ -511,6 +511,26 @@ while (<STDIN>) { synchronization takes place. +
  • +

    SQL Query
    + MapType: dbd or fastdbd, + MapSource: An SQL SELECT statement that takes a single + argument and returns a single value.

    +

    This uses mod_dbd to implement a rewritemap + by lookup in an SQL database. There are two forms: + fastdbd caches database lookups internally, + dbd doesn't. So dbd incurs a + performance penalty but responds immediately if the database + contents are updated, while fastdbd is more + efficient but won't re-read database contents until server + restart.

    +

    If a query returns more than one row, a random row from + the result set is used.

    + +Example +RewriteMap myquery "fastdbd:SELECT destination FROM rewrite WHERE source = %s" + +

    • The RewriteMap directive can occur more than once. For each mapping-function use one diff --git a/modules/mappers/mod_rewrite.c b/modules/mappers/mod_rewrite.c index fceafd606c..9b452a2d7e 100644 --- a/modules/mappers/mod_rewrite.c +++ b/modules/mappers/mod_rewrite.c @@ -54,6 +54,8 @@ #include "apr_signal.h" #include "apr_global_mutex.h" #include "apr_dbm.h" +#include "apr_dbd.h" +#include "mod_dbd.h" #if APR_HAS_THREADS #include "apr_thread_mutex.h" @@ -98,6 +100,9 @@ #include "unixd.h" #endif +static ap_dbd_t *(*dbd_acquire)(request_rec*) = NULL; +static void (*dbd_prepare)(server_rec*, const char*, const char*) = NULL; + /* * in order to improve performance on running production systems, you * may strip all rewritelog code entirely from mod_rewrite by using the @@ -159,6 +164,8 @@ #define MAPTYPE_PRG 1<<2 #define MAPTYPE_INT 1<<3 #define MAPTYPE_RND 1<<4 +#define MAPTYPE_DBD 1<<5 +#define MAPTYPE_DBD_CACHE 1<<6 #define ENGINE_DISABLED 1<<0 #define ENGINE_ENABLED 1<<1 @@ -225,6 +232,7 @@ typedef struct { char *(*func)(request_rec *, /* function pointer for internal maps */ char *); char **argv; /* argv of the external rewrite map */ + const char *dbdq; /* SQL SELECT statement for rewritemap */ } rewritemap_entry; /* special pattern types for RewriteCond */ @@ -1318,6 +1326,51 @@ static char *lookup_map_dbmfile(request_rec *r, const char *file, return value; } +static char *lookup_map_dbd(request_rec *r, char *key, const char *label) +{ + apr_status_t rv; + apr_dbd_prepared_t *stmt; + apr_dbd_results_t *res = NULL; + apr_dbd_row_t *row = NULL; + const char *ret = NULL; + int n = 0; + ap_dbd_t *db = dbd_acquire(r); + + stmt = apr_hash_get(db->prepared, label, APR_HASH_KEY_STRING); + + rv = apr_dbd_pvselect(db->driver, r->pool, db->handle, &res, + stmt, 0, key, NULL); + if (rv != 0) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "rewritemap: error querying for %s", key); + } + while (rv = apr_dbd_get_row(db->driver, r->pool, res, &row, -1), rv == 0) { + ++n; + if (ret == NULL) { + ret = apr_dbd_get_entry(db->driver, row, 0); + } + else { + /* randomise crudely amongst multiple results */ + if ((double)rand() < (double)RAND_MAX/(double)n) { + ret = apr_dbd_get_entry(db->driver, row, 0); + } + } + } + if (rv != -1) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "rewritemap: error looking up %s", key); + } + switch (n) { + case 0: + return NULL; + case 1: + return apr_pstrdup(r->pool, ret); + default: + /* what's a fair rewritelog level for this? */ + rewritelog((r, 3, NULL, "Multiple values found for %s", key)); + return apr_pstrdup(r->pool, ret); + } +} static char *lookup_map_program(request_rec *r, apr_file_t *fpin, apr_file_t *fpout, char *key) @@ -1585,6 +1638,49 @@ static char *lookup_map(request_rec *r, char *name, char *key) name, key, value)); return *value ? value : NULL; + /* + * SQL map without cache + */ + case MAPTYPE_DBD: + value = lookup_map_dbd(r, key, s->dbdq); + if (!value) { + rewritelog((r, 5, NULL, "SQL map lookup FAILED: map %s key=%s", + name, key)); + return NULL; + } + + rewritelog((r, 5, NULL, "SQL map lookup OK: map %s key=%s, val=%s", + name, key, value)); + + return value; + + /* + * SQL map with cache + */ + case MAPTYPE_DBD_CACHE: + value = get_cache_value(s->cachename, st.mtime, key, r->pool); + if (!value) { + rewritelog((r, 6, NULL, + "cache lookup FAILED, forcing new map lookup")); + + value = lookup_map_dbd(r, key, s->dbdq); + if (!value) { + rewritelog((r, 5, NULL, "SQL map lookup FAILED: map %s key=%s", + name, key)); + return NULL; + } + + rewritelog((r, 5, NULL, "SQL map lookup OK: map %s key=%s, val=%s", + name, key, value)); + + set_cache_value(s->cachename, st.mtime, key, value); + return value; + } + + rewritelog((r, 5, NULL, "cache lookup OK: map=%s[SQL] key=%s, val=%s", + name, key, value)); + return *value ? value : NULL; + /* * Program file map */ @@ -2871,6 +2967,24 @@ static const char *cmd_rewritemap(cmd_parms *cmd, void *dconf, const char *a1, newmap->dbmtype, " is invalid", NULL); } } + else if ((strncasecmp(a2, "dbd:", 4) == 0) + || (strncasecmp(a2, "fastdbd:", 8) == 0)) { + if (dbd_prepare == NULL) { + return "RewriteMap types dbd and fastdbd require mod_dbd!"; + } + if ((a2[0] == 'd') || (a2[0] == 'D')) { + newmap->type = MAPTYPE_DBD; + fname = a2+4; + } + else { + newmap->type = MAPTYPE_DBD_CACHE; + fname = a2+8; + newmap->cachename = apr_psprintf(cmd->pool, "%pp:%s", + (void *)cmd->server, a1); + } + newmap->dbdq = a1; + dbd_prepare(cmd->server, fname, newmap->dbdq); + } else if (strncasecmp(a2, "prg:", 4) == 0) { apr_tokenize_to_argv(a2 + 4, &newmap->argv, cmd->pool); @@ -4796,6 +4910,11 @@ static void ap_register_rewrite_mapfunc(char *name, rewrite_mapfunc_t *func) apr_hash_set(mapfunc_hash, name, strlen(name), (const void *)func); } +static void optional_fns(void) { + dbd_acquire = APR_RETRIEVE_OPTIONAL_FN(ap_dbd_acquire); + dbd_prepare = APR_RETRIEVE_OPTIONAL_FN(ap_dbd_prepare); +} + static void register_hooks(apr_pool_t *p) { /* fixup after mod_proxy, so that the proxied url will not @@ -4813,6 +4932,7 @@ static void register_hooks(apr_pool_t *p) ap_hook_fixups(hook_fixup, aszPre, NULL, APR_HOOK_FIRST); ap_hook_fixups(hook_mimetype, NULL, NULL, APR_HOOK_LAST); ap_hook_translate_name(hook_uri2file, NULL, NULL, APR_HOOK_FIRST); + ap_hook_optional_fn_retrieve(optional_fns, NULL, NULL, APR_HOOK_MIDDLE); } /* the main config structure */