Module cluster flags: add hooks for NO_REDIRECTION flag.

3 files changed, 14 insertions, 4 deletions

diff --git a/src/cluster.c b/src/cluster.c
index ad48641ec..591df418a 100644
--- a/src/cluster.c
+++ b/src/cluster.c
@@ -1589,6 +1589,12 @@ void clusterUpdateSlotsConfigWith(clusterNode *sender, uint64_t senderConfigEpoc
         }
     }
 
+    /* After updating the slots configuration, don't do any actual change
+     * in the state of the server if a module disabled Redis Cluster
+     * keys redirections. */
+    if (server.cluster_module_flags & CLUSTER_MODULE_FLAG_NO_REDIRECTION)
+        return;
+
     /* If at least one slot was reassigned from a node to another node
      * with a greater configEpoch, it is possible that:
      * 1) We are a master left without slots. This means that we were
@@ -5435,6 +5441,10 @@ clusterNode *getNodeByQuery(client *c, struct redisCommand *cmd, robj **argv, in
     multiCmd mc;
     int i, slot = 0, migrating_slot = 0, importing_slot = 0, missing_keys = 0;
 
+    /* Allow any key to be set if a module disabled cluster redirections. */
+    if (server.cluster_module_flags & CLUSTER_MODULE_FLAG_NO_REDIRECTION)
+        return myself;
+
     /* Set error code optimistically for the base case. */
     if (error_code) *error_code = CLUSTER_REDIR_NONE;
 
diff --git a/src/cluster.h b/src/cluster.h
index 68d7af3a4..571b9c543 100644
--- a/src/cluster.h
+++ b/src/cluster.h
@@ -103,9 +103,9 @@ typedef struct clusterLink {
 /* Flags that a module can set in order to prevent certain Redis Cluster
  * features to be enabled. Useful when implementing a different distributed
  * system on top of Redis Cluster message bus, using modules. */
-#define MODULE_CLUSTER_FLAG_NONE 0
-#define MODULE_CLUSTER_FLAG_NO_FAILOVER (1<<1)
-#define MODULE_CLUSTER_FLAG_NO_REDIRECTION (1<<2)
+#define CLUSTER_MODULE_FLAG_NONE 0
+#define CLUSTER_MODULE_FLAG_NO_FAILOVER (1<<1)
+#define CLUSTER_MODULE_FLAG_NO_REDIRECTION (1<<2)
 
 /* This structure represent elements of node->fail_reports. */
 typedef struct clusterNodeFailReport {
diff --git a/src/server.c b/src/server.c
index dee18fa6c..239434a2b 100644
--- a/src/server.c
+++ b/src/server.c
@@ -1621,7 +1621,7 @@ void initServerConfig(void) {
     server.cluster_announce_ip = CONFIG_DEFAULT_CLUSTER_ANNOUNCE_IP;
     server.cluster_announce_port = CONFIG_DEFAULT_CLUSTER_ANNOUNCE_PORT;
     server.cluster_announce_bus_port = CONFIG_DEFAULT_CLUSTER_ANNOUNCE_BUS_PORT;
-    server.cluster_module_flags = MODULE_CLUSTER_FLAG_NONE;
+    server.cluster_module_flags = CLUSTER_MODULE_FLAG_NONE;
     server.migrate_cached_sockets = dictCreate(&migrateCacheDictType,NULL);
     server.next_client_id = 1; /* Client IDs, start from 1 .*/
     server.loading_process_events_interval_bytes = (1024*1024*2);