Handle integer replies, implement a connect timeout and dynamic config in VCL

README.md

@@ -14,6 +14,17 @@ So far the module builds and runs on FreeBSD--on other platforms, you are on you
 Functions and procedures
 ------------------------
 
+*redis.init_redis(host, port, timeout_ms)*
+
+Use the redis server at the given _host_ and _port_ with a timeout
+of _timeout__ms_ milliseconds.
+If _port_ is less than or equal to zero, the default port of 6379 is used.
+If _timeout__ms_ is less than or equal to zero, a default timeout of 200ms is used.
+
+This function is supposed to be called from the Varnish subroutine _vcl__init_.
+If the call is left out, the module will attempt to connect to the Redis server
+at 127.0.0.1:6379 with a connect timeout of 200ms.
+
 *redis.send(command)*
 
 Sends the given _command_ to redis; the response will be ignored.

examples/example.vcl

@@ -9,9 +9,20 @@ backend be1 {
   .port = "80";
 }
 
+#sub vcl_init {
+  #
+  # By default, the redis module will attempt to connect to a Redis server
+  # at 127.0.0.1:6379 with a connect timeout of 200 milliseconds.
+  #
+  # The function redis.init_redis(host, port, timeout_ms) may be used to
+  # connect to an alternate Redis server or use a different connect timeout.
+  #
+  # redis.init_redis("localhost", 6379, 200);  /* default values */
+#}
+
 sub vcl_recv {
   #
-  # redis.call is a procedure, it will send the command to redis and ignore
+  # redis.send is a procedure, it will send the command to redis and ignore
   # the response. If the command errors out, it will be logged but the VCL
   # will not know.
   #

src/vmod_redis.c

@@ -1,5 +1,6 @@
 #include <stdlib.h>
 #include <stdio.h>
+#include <sys/time.h>
 
 #include "vrt.h"
 #include "bin/varnishd/cache.h"
@@ -10,6 +11,9 @@
 #include <hiredis/hiredis.h>
 
 
+#define REDIS_TIMEOUT_MS	200	/* 200 milliseconds */
+
+
 #define	LOG_E(...) fprintf(stderr, __VA_ARGS__);
 #ifdef DEBUG
 #	define	LOG_T(...) fprintf(stderr, __VA_ARGS__);
@@ -20,6 +24,7 @@
 typedef struct redisConfig {
 	char *host;
 	int port;
+	struct timeval timeout;
 } config_t;
 
 static pthread_key_t redis_key;
@@ -44,36 +49,73 @@ make_key()
 {
 	(void)pthread_key_create(&redis_key, NULL);
 }
+
+static config_t *
+make_config(const char *host, int port, int timeout_ms)
+{
+	config_t *cfg;
+
+	LOG_T("make_config(%s,%d,%d)\n", host, port, timeout_ms);
+
+	cfg = malloc(sizeof(config_t));
+	if(cfg == NULL)
+		return NULL;
+
+	if(port <= 0)
+		port = 6379;
+
+	if(timeout_ms <= 0)
+		timeout_ms = REDIS_TIMEOUT_MS;
+
+	cfg->host = strdup(host);
+	cfg->port = port;
+
+	cfg->timeout.tv_sec = timeout_ms / 1000;
+	cfg->timeout.tv_usec = (timeout_ms % 1000) * 1000;
+
+	return cfg;
+}
 
 int
 init_function(struct vmod_priv *priv, const struct VCL_conf *conf)
 {
+	config_t *cfg;
+
 	LOG_T("redis init called\n");
 
 	(void)pthread_once(&redis_key_once, make_key);
 
+	if (priv->priv == NULL) {
+		priv->priv = make_config("127.0.0.1", 6379, REDIS_TIMEOUT_MS);
+		priv->free = free;
+	}
+
 	return (0);
 }
 
+void
+vmod_init_redis(struct sess *sp, struct vmod_priv *priv, const char *host, int port, int timeout_ms)
+{
+	config_t *old_cfg = priv->priv;
+
+	priv->priv = make_config(host, port, timeout_ms);
+	if(priv->priv && old_cfg) {
+		free(old_cfg->host);
+		free(old_cfg);
+	}
+}
+
 static redisReply *
 redis_common(struct sess *sp, struct vmod_priv *priv, const char *command)
 {
-	config_t *cfg;
+	config_t *cfg = priv->priv;
 	redisContext *c;
 	redisReply *reply = NULL;
 
 	LOG_T("redis(%x): running %s %p\n", pthread_self(), command, priv->priv);
 
-	cfg = priv->priv;
-	if (cfg == NULL) {
-		priv->priv = cfg = malloc(sizeof(config_t));
-		priv->free = free;
-		cfg->host = strdup("127.0.0.1");
-		cfg->port = 6379;
-	}
-
 	if ((c = pthread_getspecific(redis_key)) == NULL) {
-		c = redisConnect(cfg->host, cfg->port);
+		c = redisConnectWithTimeout(cfg->host, cfg->port, cfg->timeout);
 		if (c->err) {
 			LOG_E("redis error (connect): %s\n", c->errstr);
 		}
@@ -82,7 +124,7 @@ redis_common(struct sess *sp, struct vmod_priv *priv, const char *command)
 
 	reply = redisCommand(c, command);
 	if (reply == NULL && c->err == REDIS_ERR_EOF) {
-		c = redisConnect(cfg->host, cfg->port);
+		c = redisConnectWithTimeout(cfg->host, cfg->port, cfg->timeout);
 		if (c->err) {
 			LOG_E("redis error (reconnect): %s\n", c->errstr);
 			redisFree(c);
@@ -114,6 +156,7 @@ vmod_call(struct sess *sp, struct vmod_priv *priv, const char *command)
 {
 	redisReply *reply = NULL;
 	const char *ret = NULL;
+	char *digits;
 
 	reply = redis_common(sp, priv, command);
 	if (reply == NULL) {
@@ -128,7 +171,10 @@ vmod_call(struct sess *sp, struct vmod_priv *priv, const char *command)
 		ret = strdup(reply->str);
 		break;
 	case REDIS_REPLY_INTEGER:
-		ret = strdup("integer");	/* FIXME */
+		digits = malloc(21); /* sizeof(long long) == 8; 20 digits + NUL */
+		if(digits)
+			sprintf(digits, "%lld", reply->integer);
+		ret = digits;
 		break;
 	case REDIS_REPLY_NIL:
 		ret = NULL;

src/vmod_redis.vcc

@@ -1,4 +1,5 @@
 Module redis
 Init init_function
-Function VOID send(PRIV_CALL, STRING)
-Function STRING call(PRIV_CALL, STRING)
+Function VOID init_redis(PRIV_VCL, STRING, INT, INT)
+Function VOID send(PRIV_VCL, STRING)
+Function STRING call(PRIV_VCL, STRING)