From 3571a648ae0e2620ba9fcfec6033a6d604219824 Mon Sep 17 00:00:00 2001
From: Pavel Rochnyack <pavel2000@ngs.ru>
Date: Thu, 23 Aug 2018 14:35:19 +0700
Subject: [PATCH] redis plugin: Added option for connecting via UNIX socket

---
 src/collectd.conf.in  |  1 +
 src/collectd.conf.pod |  6 ++++++
 src/redis.c           | 28 +++++++++++++++++++++++-----
 3 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/src/collectd.conf.in b/src/collectd.conf.in
index fb1471f1..af652145 100644
--- a/src/collectd.conf.in
+++ b/src/collectd.conf.in
@@ -1276,6 +1276,7 @@
 #   <Node example>
 #      Host "redis.example.com"
 #      Port "6379"
+#      #Socket "/var/run/redis/redis.sock"
 #      Timeout 2000
 #      <Query "LLEN myqueue">
 #        #Database 0
diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index 1134541a..6e6d6eaf 100644
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -7359,6 +7359,7 @@ parameters and set of user-defined queries for this node.
     <Node "example">
         Host "localhost"
         Port "6379"
+        #Socket "/var/run/redis/redis.sock"
         Timeout 2000
         ReportCommandStats false
         ReportCpuUsage true
@@ -7392,6 +7393,11 @@ The B<Port> option is the TCP port on which the Redis instance accepts
 connections. Either a service name of a port number may be given. Please note
 that numerical port numbers must be given as a string, too.
 
+=item B<Socket> I<Path>
+
+Connect to Redis using the UNIX domain socket at I<Path>. If this
+setting is given, the B<Hostname> and B<Port> settings are ignored.
+
 =item B<Password> I<Password>
 
 Use I<Password> to authenticate when connecting to I<Redis>.
diff --git a/src/redis.c b/src/redis.c
index dd4deb17..e24abd54 100644
--- a/src/redis.c
+++ b/src/redis.c
@@ -70,6 +70,7 @@ typedef struct redis_node_s redis_node_t;
 struct redis_node_s {
   char *name;
   char *host;
+  char *socket;
   char *passwd;
   int port;
   struct timeval timeout;
@@ -101,6 +102,7 @@ static void redis_node_free(void *arg) {
     redisFree(rn->redisContext);
   sfree(rn->name);
   sfree(rn->host);
+  sfree(rn->socket);
   sfree(rn->passwd);
   sfree(rn);
 } /* void redis_node_free */
@@ -213,6 +215,8 @@ static int redis_config_node(oconfig_item_t *ci) /* {{{ */
         rn->port = status;
         status = 0;
       }
+    } else if (strcasecmp("Socket", option->key) == 0) {
+      status = cf_util_get_string(option, &rn->socket);
     } else if (strcasecmp("Query", option->key) == 0) {
       redis_query_t *rq = redis_config_query(option);
       if (rq == NULL) {
@@ -591,15 +595,23 @@ static void redis_check_connection(redis_node_t *rn) {
   if (rn->redisContext)
     return;
 
-  redisContext *rh = redisConnectWithTimeout(rn->host, rn->port, rn->timeout);
+  redisContext *rh;
+  if (rn->socket != NULL)
+    rh = redisConnectUnixWithTimeout(rn->socket, rn->timeout);
+  else
+    rh = redisConnectWithTimeout(rn->host, rn->port, rn->timeout);
 
   if (rh == NULL) {
     ERROR("redis plugin: can't allocate redis context");
     return;
   }
   if (rh->err) {
-    ERROR("redis plugin: unable to connect to node `%s' (%s:%d): %s.", rn->name,
-          rn->host, rn->port, rh->errstr);
+    if (rn->socket)
+      ERROR("redis plugin: unable to connect to node `%s' (%s): %s.", rn->name,
+            rn->socket, rh->errstr);
+    else
+      ERROR("redis plugin: unable to connect to node `%s' (%s:%d): %s.",
+            rn->name, rn->host, rn->port, rh->errstr);
     redisFree(rh);
     return;
   }
@@ -760,8 +772,14 @@ static int redis_read(user_data_t *user_data) /* {{{ */
 {
   redis_node_t *rn = user_data->data;
 
-  DEBUG("redis plugin: querying info from node `%s' (%s:%d).", rn->name,
-        rn->host, rn->port);
+#if COLLECT_DEBUG
+  if (rn->socket)
+    DEBUG("redis plugin: querying info from node `%s' (%s).", rn->name,
+          rn->socket);
+  else
+    DEBUG("redis plugin: querying info from node `%s' (%s:%d).", rn->name,
+          rn->host, rn->port);
+#endif
 
   redis_check_connection(rn);
 
-- 
2.11.0