Redis TTL

cachedb/cachedb.c

@@ -160,7 +160,7 @@ testframe_lookup(struct module_env* env, struct cachedb_env* cachedb_env,
 
 static void
 testframe_store(struct module_env* env, struct cachedb_env* cachedb_env,
-	char* key, uint8_t* data, size_t data_len)
+	char* key, uint8_t* data, size_t data_len, uint64_t ttl)
 {
 	struct testframe_moddata* d = (struct testframe_moddata*)
 		cachedb_env->backend_data;
@@ -606,7 +606,8 @@ cachedb_extcache_store(struct module_qstate* qstate, struct cachedb_env* ie)
 	/* call backend */
 	(*ie->backend->store)(qstate->env, ie, key,
 		sldns_buffer_begin(qstate->env->scratch_buffer),
-		sldns_buffer_limit(qstate->env->scratch_buffer));
+		sldns_buffer_limit(qstate->env->scratch_buffer),
+		(uint64_t)qstate->return_msg->rep->ttl);
 }
 
 /**

cachedb/cachedb.h

@@ -84,7 +84,7 @@ struct cachedb_backend {
 
 	/** Store (env, cachedb_env, key, data, data_len) */
 	void (*store)(struct module_env*, struct cachedb_env*, char*,
-		uint8_t*, size_t);
+		uint8_t*, size_t, uint64_t);
 };
 
 #define CACHEDB_HASHSIZE 256 /* bit hash */

cachedb/redis.c

@@ -47,6 +47,7 @@
 #include "util/alloc.h"
 #include "util/config_file.h"
 #include "sldns/sbuffer.h"
+#include <stdbool.h>
 
 #ifdef USE_REDIS
 #include "hiredis/hiredis.h"
@@ -249,16 +250,37 @@ redis_lookup(struct module_env* env, struct cachedb_env* cachedb_env,
 
 static void
 redis_store(struct module_env* env, struct cachedb_env* cachedb_env,
-	char* key, uint8_t* data, size_t data_len)
+	char* key, uint8_t* data, size_t data_len, uint64_t ttl)
 {
 	redisReply* rep;
-	char cmdbuf[4+(CACHEDB_HASHSIZE/8)*2+3+1]; /* "SET " + key + " %b" */
 	int n;
+	int size;
+	bool set_ttl = !env->cfg->serve_expired || env->cfg->serve_expired_ttl > 0;
 
-	verbose(VERB_ALGO, "redis_store %s (%d bytes)", key, (int)data_len);
+        if (env->cfg->serve_expired_ttl > 0) {
+		ttl += env->cfg->serve_expired_ttl;
+	}
+
+	if (!set_ttl) {
+		size = 4+(CACHEDB_HASHSIZE/8)*2+3+1;
+	}
+	else {
+		size = 4+(CACHEDB_HASHSIZE/8)*2+3+4+sizeof(uint64_t)+1;
+	}
+
+	char cmdbuf[size]; /* "SET " + key + " %b EX " + ttl */
+
+	if (!set_ttl) {
+		verbose(VERB_ALGO, "redis_store %s (%d bytes)", key, (int)data_len);
+		/* build command to set to a binary safe string */
+		n = snprintf(cmdbuf, sizeof(cmdbuf), "SET %s %%b", key);
+	}
+	else {
+		verbose(VERB_ALGO, "redis_store %s (%d bytes) with ttl %d", key, (int)data_len, ttl);
+		/* build command to set to a binary safe string */
+		n = snprintf(cmdbuf, sizeof(cmdbuf), "SET %s %%b EX %d", key, ttl);
+	}
 
-	/* build command to set to a binary safe string */
-	n = snprintf(cmdbuf, sizeof(cmdbuf), "SET %s %%b", key);
 	if(n < 0 || n >= (int)sizeof(cmdbuf)) {
 		log_err("redis_store: unexpected failure to build command");
 		return;