Initial commit of ASK redirection fix

michael-grunder · michael-grunder · commit ba73fbee7471 · 2020-01-31T09:14:22.000-08:00
See #1693
diff --git a/cluster_library.c b/cluster_library.c
@@ -1206,8 +1206,7 @@ static int cluster_set_redirection(redisCluster* c, char *msg, int moved)
  *
  * This function will return -1 on a critical error (e.g. parse/communication
  * error, 0 if no redirection was encountered, and 1 if the data was moved. */
-static int cluster_check_response(redisCluster *c, REDIS_REPLY_TYPE *reply_type
-                                 )
+static int cluster_check_response(redisCluster *c, REDIS_REPLY_TYPE *reply_type)
 {
     size_t sz;
 
@@ -1232,15 +1231,17 @@ static int cluster_check_response(redisCluster *c, REDIS_REPLY_TYPE *reply_type
         }
 
         // Check for MOVED or ASK redirection
-        if ((moved = IS_MOVED(inbuf)) || IS_ASK(inbuf)) { // Set our redirection information
-            /* We'll want to invalidate slot cache if we're using one */
-            c->redirections++;
+        if ((moved = IS_MOVED(inbuf)) || IS_ASK(inbuf)) {
+            /* The Redis Cluster specification suggests clients do not update
+             * their slot mapping for an ASK redirection, only for MOVED */
+            if (moved) c->redirections++;
 
+            /* Make sure we can parse the redirection host and port */
             if (cluster_set_redirection(c,inbuf,moved) < 0) {
                 return -1;
             }
 
-            // Data moved
+            /* We've been redirected */
             return 1;
         } else {
             // Capture the error string Redis returned
@@ -1380,8 +1381,7 @@ static int cluster_sock_write(redisCluster *c, const char *cmd, size_t sz,
     /* If in ASK redirection, get/create the node for that host:port, otherwise
      * just use the command socket. */
     if (c->redir_type == REDIR_ASK) {
-        redis_sock = cluster_get_asking_sock(c);
-        if (cluster_send_asking(redis_sock) < 0) {
+        if (cluster_send_asking(c->cmd_sock) < 0) {
             return -1;
         }
     }
@@ -1627,10 +1627,13 @@ PHP_REDIS_API short cluster_send_command(redisCluster *c, short slot, const char
                return -1;
            }
 
-           /* Update mapping if the data has MOVED */
            if (c->redir_type == REDIR_MOVED) {
+               /* For MOVED redirection we want to update our cached mapping */
                cluster_update_slot(c);
                c->cmd_sock = SLOT_SOCK(c, slot);
+           } else if (c->redir_type == REDIR_ASK) {
+               /* For ASK redirection we want to redirect but not update slot mapping */
+               c->cmd_sock = cluster_get_asking_sock(c);
            }
         }
 
diff --git a/cluster_library.h b/cluster_library.h
@@ -26,7 +26,7 @@
 /* MOVED/ASK comparison macros */
 #define IS_MOVED(p) (p[0]=='M' && p[1]=='O' && p[2]=='V' && p[3]=='E' && \
                      p[4]=='D' && p[5]==' ')
-#define IS_ASK(p)   (p[0]=='A' && p[1]=='S' && p[3]=='K' && p[4]==' ')
+#define IS_ASK(p)   (p[0]=='A' && p[1]=='S' && p[2]=='K' && p[3]==' ')
 
 /* MOVED/ASK lengths */
 #define MOVED_LEN (sizeof("MOVED ")-1)

Original file line number	Diff line number	Diff line change
`@@ -1206,8 +1206,7 @@ static int cluster_set_redirection(redisCluster* c, char *msg, int moved)`
`1206`	`1206`	`*`
`1207`	`1207`	`* This function will return -1 on a critical error (e.g. parse/communication`
`1208`	`1208`	`* error, 0 if no redirection was encountered, and 1 if the data was moved. */`
`1209`		`-static int cluster_check_response(redisCluster c, REDIS_REPLY_TYPE reply_type`
`1210`		`- )`
	`1209`	`+static int cluster_check_response(redisCluster c, REDIS_REPLY_TYPE reply_type)`
`1211`	`1210`	`{`
`1212`	`1211`	`size_t sz;`
`1213`	`1212`
`@@ -1232,15 +1231,17 @@ static int cluster_check_response(redisCluster c, REDIS_REPLY_TYPE reply_type`
`1232`	`1231`	`}`
`1233`	`1232`
`1234`	`1233`	`// Check for MOVED or ASK redirection`
`1235`		`- if ((moved = IS_MOVED(inbuf)) \|\| IS_ASK(inbuf)) { // Set our redirection information`
`1236`		`- /* We'll want to invalidate slot cache if we're using one */`
`1237`		`- c->redirections++;`
	`1234`	`+ if ((moved = IS_MOVED(inbuf)) \|\| IS_ASK(inbuf)) {`
	`1235`	`+ /* The Redis Cluster specification suggests clients do not update`
	`1236`	`+ * their slot mapping for an ASK redirection, only for MOVED */`
	`1237`	`+ if (moved) c->redirections++;`
`1238`	`1238`
	`1239`	`+ /* Make sure we can parse the redirection host and port */`
`1239`	`1240`	`if (cluster_set_redirection(c,inbuf,moved) < 0) {`
`1240`	`1241`	`return -1;`
`1241`	`1242`	`}`
`1242`	`1243`
`1243`		`- // Data moved`
	`1244`	`+ /* We've been redirected */`
`1244`	`1245`	`return 1;`
`1245`	`1246`	`} else {`
`1246`	`1247`	`// Capture the error string Redis returned`
`@@ -1380,8 +1381,7 @@ static int cluster_sock_write(redisCluster c, const char cmd, size_t sz,`
`1380`	`1381`	`/* If in ASK redirection, get/create the node for that host:port, otherwise`
`1381`	`1382`	`* just use the command socket. */`
`1382`	`1383`	`if (c->redir_type == REDIR_ASK) {`
`1383`		`- redis_sock = cluster_get_asking_sock(c);`
`1384`		`- if (cluster_send_asking(redis_sock) < 0) {`
	`1384`	`+ if (cluster_send_asking(c->cmd_sock) < 0) {`
`1385`	`1385`	`return -1;`
`1386`	`1386`	`}`
`1387`	`1387`	`}`
`@@ -1627,10 +1627,13 @@ PHP_REDIS_API short cluster_send_command(redisCluster *c, short slot, const char`
`1627`	`1627`	`return -1;`
`1628`	`1628`	`}`
`1629`	`1629`
`1630`		`- /* Update mapping if the data has MOVED */`
`1631`	`1630`	`if (c->redir_type == REDIR_MOVED) {`
	`1631`	`+ /* For MOVED redirection we want to update our cached mapping */`
`1632`	`1632`	`cluster_update_slot(c);`
`1633`	`1633`	`c->cmd_sock = SLOT_SOCK(c, slot);`
	`1634`	`+ } else if (c->redir_type == REDIR_ASK) {`
	`1635`	`+ /* For ASK redirection we want to redirect but not update slot mapping */`
	`1636`	`+ c->cmd_sock = cluster_get_asking_sock(c);`
`1634`	`1637`	`}`
`1635`	`1638`	`}`
`1636`	`1639`