http: Add "if" option to match object

src/nxt_conf_validation.c

@@ -684,6 +684,10 @@ static nxt_conf_vldt_object_t  nxt_conf_vldt_match_members[] = {
         .type       = NXT_CONF_VLDT_OBJECT | NXT_CONF_VLDT_ARRAY,
         .validator  = nxt_conf_vldt_match_patterns_sets,
         .u.string   = "cookies"
+    }, {
+        .name       = nxt_string("if"),
+        .type       = NXT_CONF_VLDT_STRING,
+        .flags      = NXT_CONF_VLDT_TSTR,
     },
 
     NXT_CONF_VLDT_END

src/nxt_http_route.c

@@ -51,6 +51,7 @@ typedef struct {
     nxt_conf_value_t               *query;
     nxt_conf_value_t               *source;
     nxt_conf_value_t               *destination;
+    nxt_conf_value_t               *condition;
 } nxt_http_route_match_conf_t;
 
 
@@ -138,6 +139,7 @@ typedef union {
 
 typedef struct {
     uint32_t                       items;
+    nxt_tstr_t                     *condition;
     nxt_http_action_t              action;
     nxt_http_route_test_t          test[];
 } nxt_http_route_match_t;
@@ -204,6 +206,8 @@ static nxt_http_action_t *nxt_http_route_handler(nxt_task_t *task,
     nxt_http_request_t *r, nxt_http_action_t *start);
 static nxt_http_action_t *nxt_http_route_match(nxt_task_t *task,
     nxt_http_request_t *r, nxt_http_route_match_t *match);
+static nxt_int_t nxt_http_route_match_if(nxt_task_t *task,
+    nxt_http_request_t *r, nxt_tstr_t *condition);
 static nxt_int_t nxt_http_route_table(nxt_http_request_t *r,
     nxt_http_route_table_t *table);
 static nxt_int_t nxt_http_route_ruleset(nxt_http_request_t *r,
@@ -350,6 +354,12 @@ static nxt_conf_map_t  nxt_http_route_match_conf[] = {
         NXT_CONF_MAP_PTR,
         offsetof(nxt_http_route_match_conf_t, destination),
     },
+
+    {
+        nxt_string("if"),
+        NXT_CONF_MAP_PTR,
+        offsetof(nxt_http_route_match_conf_t, condition),
+    },
 };
 
 
@@ -397,14 +407,17 @@ nxt_http_route_match_create(nxt_task_t *task, nxt_router_temp_conf_t *tmcf,
     uint32_t                     n;
     nxt_mp_t                     *mp;
     nxt_int_t                    ret;
-    nxt_conf_value_t             *match_conf, *action_conf;
+    nxt_str_t                    str;
+    nxt_conf_value_t             *match_conf, *action_conf, *condition;
+    nxt_router_conf_t            *rtcf;
     nxt_http_route_test_t        *test;
     nxt_http_route_rule_t        *rule;
     nxt_http_route_table_t       *table;
     nxt_http_route_match_t       *match;
     nxt_http_route_addr_rule_t   *addr_rule;
     nxt_http_route_match_conf_t  mtcf;
 
+    static const nxt_str_t  if_path = nxt_string("/if");
     static const nxt_str_t  match_path = nxt_string("/match");
     static const nxt_str_t  action_path = nxt_string("/action");
 
@@ -413,9 +426,21 @@ nxt_http_route_match_create(nxt_task_t *task, nxt_router_temp_conf_t *tmcf,
     n = (match_conf != NULL) ? nxt_conf_object_members_count(match_conf) : 0;
     size = sizeof(nxt_http_route_match_t) + n * sizeof(nxt_http_route_test_t *);
 
-    mp = tmcf->router_conf->mem_pool;
+    rtcf = tmcf->router_conf;
+    mp = rtcf->mem_pool;
+
+    condition = NULL;
+
+    if (match_conf != NULL) {
+        condition = nxt_conf_get_path(match_conf, &if_path);
+
+        if (condition != NULL) {
+            n--;
+            size -= sizeof(nxt_http_route_test_t *);
+        }
+    }
 
-    match = nxt_mp_alloc(mp, size);
+    match = nxt_mp_zalloc(mp, size);
     if (nxt_slow_path(match == NULL)) {
         return NULL;
     }
@@ -432,7 +457,7 @@ nxt_http_route_match_create(nxt_task_t *task, nxt_router_temp_conf_t *tmcf,
         return NULL;
     }
 
-    if (n == 0) {
+    if (n == 0 && condition == NULL) {
         return match;
     }
 
@@ -445,6 +470,15 @@ nxt_http_route_match_create(nxt_task_t *task, nxt_router_temp_conf_t *tmcf,
         return NULL;
     }
 
+    if (condition != NULL) {
+        nxt_conf_get_string(condition, &str);
+
+        match->condition = nxt_tstr_compile(rtcf->tstr_state, &str, 0);
+        if (nxt_slow_path(match->condition == NULL)) {
+            return NULL;
+        }
+    }
+
     test = &match->test[0];
 
     if (mtcf.scheme != NULL) {
@@ -1594,8 +1628,17 @@ nxt_http_route_match(nxt_task_t *task, nxt_http_request_t *r,
     nxt_http_route_match_t *match)
 {
     nxt_int_t              ret;
+    nxt_http_action_t      *action;
     nxt_http_route_test_t  *test, *end;
 
+    if (match->condition != NULL) {
+        ret = nxt_http_route_match_if(task, r, match->condition);
+        if (ret <= 0) {
+            action = (nxt_http_action_t *) (intptr_t) ret;
+            return action;
+        }
+    }
+
     test = &match->test[0];
     end = test + match->items;
 
@@ -1631,6 +1674,40 @@ nxt_http_route_match(nxt_task_t *task, nxt_http_request_t *r,
 }
 
 
+static nxt_int_t
+nxt_http_route_match_if(nxt_task_t *task, nxt_http_request_t *r,
+    nxt_tstr_t *condition)
+{
+    nxt_int_t          ret;
+    nxt_str_t          str;
+    nxt_router_conf_t  *rtcf;
+
+    rtcf = r->conf->socket_conf->router_conf;
+
+    ret = nxt_tstr_query_init(&r->tstr_query, rtcf->tstr_state, &r->tstr_cache,
+                              r, r->mem_pool);
+    if (nxt_slow_path(ret != NXT_OK)) {
+        return NXT_ERROR;
+    }
+
+    ret = nxt_tstr_query(task, r->tstr_query, condition, &str);
+    if (nxt_slow_path(ret != NXT_OK)) {
+        return NXT_ERROR;
+    }
+
+    if (str.length == 0
+        || nxt_str_eq(&str, "0", 1)
+        || nxt_str_eq(&str, "false", 5)
+        || nxt_str_eq(&str, "null", 4)
+        || nxt_str_eq(&str, "undefined", 9))
+    {
+        return 0;
+    }
+
+    return 1;
+}
+
+
 static nxt_int_t
 nxt_http_route_table(nxt_http_request_t *r, nxt_http_route_table_t *table)
 {