From: James Brown <jbrown@easypost.com>
Date: Thu, 22 Oct 2015 01:19:05 +0000 (-0700)
Subject: MINOR: check: add agent-send server parameter
X-Git-Tag: v1.7-dev1~52
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=55f9ff11b507eccfebb8f212962e675551d61c7b;p=thirdparty%2Fhaproxy.git

MINOR: check: add agent-send server parameter

Causes HAProxy to emit a static string to the agent on every check,
so that you can independently control multiple services running
behind a single agent port.
---

diff --git a/doc/configuration.txt b/doc/configuration.txt
index 7dea0f6c4a..c3966d709b 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -10058,6 +10058,13 @@ agent-check
 
   Supported in default-server: No
 
+agent-send <string>
+  If this option is specified, haproxy will send the given string (verbatim)
+  to the agent server upon connection. You could, for example, encode
+  the backend name into this string, which would enable your agent to send
+  different responses based on the backend. Make sure to include a '\n' if
+  you want to terminate your request with a newline.
+
 agent-inter <delay>
   The "agent-inter" parameter sets the interval between two agent checks
   to <delay> milliseconds. If left unspecified, the delay defaults to 2000 ms.
diff --git a/include/types/checks.h b/include/types/checks.h
index 02fc743751..dd2018400a 100644
--- a/include/types/checks.h
+++ b/include/types/checks.h
@@ -176,6 +176,8 @@ struct check {
 						 * rise to rise+fall-1 = good */
 	int rise, fall;				/* time in iterations */
 	int type;				/* Check type, one of PR_O2_*_CHK */
+	char *send_string;			/* optionally send a string when connecting to the agent */
+	int send_string_len;			/* length of agent command string */
 	struct server *server;			/* back-pointer to server */
 	char **argv;				/* the arguments to use if running a process-based check */
 	char **envp;				/* the environment to use if running a process-based check */
diff --git a/src/checks.c b/src/checks.c
index 997cf81202..e77926ac3d 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -1459,6 +1459,10 @@ static int connect_conn_chk(struct task *t)
 		}
 	}
 
+	if ((check->type & PR_O2_LB_AGENT_CHK) && check->send_string_len) {
+		bo_putblk(check->bo, check->send_string, check->send_string_len);
+	}
+
 	/* prepare a new connection */
 	conn_init(conn);
 
diff --git a/src/haproxy.c b/src/haproxy.c
index 93423a9b09..973af29182 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -1412,6 +1412,7 @@ void deinit(void)
 			free(s->check.bo);
 			free(s->agent.bi);
 			free(s->agent.bo);
+			free(s->agent.send_string);
 			free((char*)s->conf.file);
 #ifdef USE_OPENSSL
 			if (s->use_ssl || s->check.use_ssl)
diff --git a/src/server.c b/src/server.c
index c92623d481..224d536f19 100644
--- a/src/server.c
+++ b/src/server.c
@@ -984,6 +984,9 @@ int parse_server(const char *file, int linenum, char **args, struct proxy *curpr
 			newsrv->check.downinter	= curproxy->defsrv.check.downinter;
 			newsrv->agent.use_ssl	= curproxy->defsrv.agent.use_ssl;
 			newsrv->agent.port	= curproxy->defsrv.agent.port;
+			if (curproxy->defsrv.agent.send_string != NULL)
+				newsrv->agent.send_string = strdup(curproxy->defsrv.agent.send_string);
+			newsrv->agent.send_string_len = curproxy->defsrv.agent.send_string_len;
 			newsrv->agent.inter	= curproxy->defsrv.agent.inter;
 			newsrv->agent.fastinter	= curproxy->defsrv.agent.fastinter;
 			newsrv->agent.downinter	= curproxy->defsrv.agent.downinter;
@@ -1052,6 +1055,14 @@ int parse_server(const char *file, int linenum, char **args, struct proxy *curpr
 				newsrv->agent.port = atol(args[cur_arg + 1]);
 				cur_arg += 2;
 			}
+			else if (!strcmp(args[cur_arg], "agent-send")) {
+				global.maxsock++;
+				free(newsrv->agent.send_string);
+				newsrv->agent.send_string_len = strlen(args[cur_arg + 1]);
+				newsrv->agent.send_string = calloc(1, newsrv->agent.send_string_len + 1);
+				memcpy(newsrv->agent.send_string, args[cur_arg + 1], newsrv->agent.send_string_len);
+				cur_arg += 2;
+			}
 			else if (!defsrv && !strcmp(args[cur_arg], "cookie")) {
 				newsrv->cookie = strdup(args[cur_arg + 1]);
 				newsrv->cklen = strlen(args[cur_arg + 1]);