[MEDIUM] add the "fail" condition to monitor requests
Under certain circumstances, it is very useful to be able to fail some
monitor requests. One specific case is when the number of servers in
the backend falls below a certain level. The new "monitor fail" construct
followed by either "if"/"unless" <condition> makes it possible to specify
ACL-based conditions which will make the monitor return 503 instead of
200. Any number of conditions can be passed. Another use may be to limit
the requests to local networks only.
diff --git a/src/cfgparse.c b/src/cfgparse.c
index 869567f..232ae1c 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -564,6 +564,7 @@
LIST_INIT(&curproxy->pendconns);
LIST_INIT(&curproxy->acl);
LIST_INIT(&curproxy->block_cond);
+ LIST_INIT(&curproxy->mon_fail_cond);
LIST_INIT(&curproxy->switching_rules);
/* Timeouts are defined as -1, so we cannot use the zeroed area
@@ -1305,6 +1306,38 @@
return -1;
}
}
+ else if (!strcmp(args[0], "monitor")) {
+ if (warnifnotcap(curproxy, PR_CAP_FE, file, linenum, args[0], NULL))
+ return 0;
+
+ if (strcmp(args[1], "fail") == 0) {
+ /* add a condition to fail monitor requests */
+ int pol = ACL_COND_NONE;
+ struct acl_cond *cond;
+
+ if (!strcmp(args[2], "if"))
+ pol = ACL_COND_IF;
+ else if (!strcmp(args[2], "unless"))
+ pol = ACL_COND_UNLESS;
+
+ if (pol == ACL_COND_NONE) {
+ Alert("parsing [%s:%d] : '%s %s' requires either 'if' or 'unless' followed by a condition.\n",
+ file, linenum, args[0], args[1]);
+ return -1;
+ }
+
+ if ((cond = parse_acl_cond((const char **)args + 3, &curproxy->acl, pol)) == NULL) {
+ Alert("parsing [%s:%d] : error detected while parsing a '%s %s' condition.\n",
+ file, linenum, args[0], args[1]);
+ return -1;
+ }
+ LIST_ADDQ(&curproxy->mon_fail_cond, &cond->list);
+ }
+ else {
+ Alert("parsing [%s:%d] : '%s' only supports 'fail'.\n", file, linenum, args[0]);
+ return -1;
+ }
+ }
#ifdef TPROXY
else if (!strcmp(args[0], "transparent")) {
/* enable transparent proxy connections */