RREPLAY command now takes a DB argument

Former-commit-id: 6e1e5bd08b59f8ad4653621a6c01fcf3a76f0692

src/debug.cpp

@@ -682,10 +682,12 @@ NULL
         changeReplicationId();
         clearReplicationId2();
         addReply(c,shared.ok);
-    } else if (!strcasecmp(szFromObj(c->argv[1]),"stringmatch-test") && c->argc == 2)
-    {
+    } else if (!strcasecmp(szFromObj(c->argv[1]),"stringmatch-test") && c->argc == 2) {
         stringmatchlen_fuzz_test();
         addReplyStatus(c,"Apparently Redis did not crash: test passed");
+    } else if (!strcasecmp(szFromObj(c->argv[1]), "force-master") && c->argc == 2) {
+        c->flags |= CLIENT_MASTER | CLIENT_MASTER_FORCE_REPLY;
+        addReply(c, shared.ok);
     } else {
         addReplySubcommandSyntaxError(c);
         return;

src/replication.cpp

@@ -323,9 +323,13 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) {
     char uuid[40] = {'\0'};
     uuid_unparse(cserver.uuid, uuid);
     char proto[1024];
-    int cchProto = snprintf(proto, sizeof(proto), "*3\r\n$7\r\nRREPLAY\r\n$%d\r\n%s\r\n$%lld\r\n", (int)strlen(uuid), uuid, cchbuf);
+    int cchProto = snprintf(proto, sizeof(proto), "*4\r\n$7\r\nRREPLAY\r\n$%d\r\n%s\r\n$%lld\r\n", (int)strlen(uuid), uuid, cchbuf);
     cchProto = std::min((int)sizeof(proto), cchProto);
     long long master_repl_offset_start = g_pserver->master_repl_offset;
+    
+    serverAssert(dictid >= 0);
+    char szDbNum[128];
+    int cchDbNum = snprintf(szDbNum, sizeof(szDbNum), "$%d\r\n%d\r\n", (dictid/10)+1, dictid);
 
     /* Write the command to the replication backlog if any. */
     if (g_pserver->repl_backlog) 
@@ -368,6 +372,7 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) {
             }
             const char *crlf = "\r\n";
             feedReplicationBacklog(crlf, 2);
+            feedReplicationBacklog(szDbNum, cchDbNum);
         }
     }
 
@@ -396,7 +401,10 @@ void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) {
             addReplyProtoAsync(slave, reply->buf(), reply->used);
         }
         if (!fSendRaw)
+        {
             addReplyAsync(slave,shared.crlf);
+            addReplyProtoAsync(slave, szDbNum, cchDbNum);
+        }
     }
 
     freeClient(fake);
@@ -3266,6 +3274,7 @@ void replicaReplayCommand(client *c)
     // the replay command contains two arguments: 
     //  1: The UUID of the source
     //  2: The raw command buffer to be replayed
+    //  3: (OPTIONAL) the database ID the command should apply to
     
     if (!(c->flags & CLIENT_MASTER))
     {
@@ -3298,6 +3307,17 @@ void replicaReplayCommand(client *c)
         return;
     }
 
+    if (c->argc >= 4)
+    {
+        long long db;
+        if (getLongLongFromObject(c->argv[3], &db) != C_OK || db >= cserver.dbnum || selectDb(c, (int)db) != C_OK)
+        {
+            addReplyError(c, "Invalid database ID");
+            s_pstate->Cancel();
+            return;
+        }
+    }
+
     if (FSameUuidNoNil(uuid, cserver.uuid))
     {
         addReply(c, shared.ok);

tests/integration/replication-active.tcl

@@ -93,5 +93,18 @@ start_server {tags {"active-repl"} overrides {active-replica yes}} {
             assert_equal {0} [$master del testkey1]
             assert_equal {0} [$slave del testkey1]
         }
+
+        test {Active replica different databases} {
+            $master select 3
+            $master set testkey abcd
+            $master select 2
+            $master del testkey
+            $slave select 3
+            wait_for_condition 50 1000 {
+                [string match abcd [$slave get testkey]]
+            } else {
+                fail "Replication failed to propogate DB 3"
+            }
+        }
     }
 }

tests/test_helper.tcl

@@ -35,6 +35,7 @@ set ::all_tests {
     unit/quit
     unit/aofrw
     unit/acl
+    unit/rreplay
     integration/block-repl
     integration/replication
     integration/replication-2

tests/unit/rreplay.tcl

@@ -0,0 +1,30 @@
+start_server {tags {"rreplay"}} {
+
+    test {RREPLAY use current db} {
+        r debug force-master
+        r select 4
+        r set dbnum invalid
+        r rreplay "f4d5b2b5-4f07-4ee5-a4f2-5dc98507dfce" "*3\r\n\$3\r\nSET\r\n\$5\r\ndbnum\r\n\$4\r\nfour\r\n"
+        r get dbnum
+    } {four}
+    reconnect
+
+    test {RREPLAY db different} {
+        r debug force-master
+        r select 4
+        r set testkey four
+        r rreplay "f4d5b2b5-4f07-4ee5-a4f2-5dc98507dfce" "*3\r\n\$3\r\nSET\r\n\$7\r\ntestkey\r\n\$4\r\nbebe\r\n" 2
+        r select 4
+        assert { [r get testkey] == "four" }
+        r select 2
+        r get testkey
+    } {bebe}
+
+    reconnect
+
+    test {RREPLAY not master} {
+        assert_error "*master*" {r rreplay "f4d5b2b5-4f07-4ee5-a4f2-5dc98507dfce" "*3\r\n\$3\r\nSET\r\n\$7\r\ntestkey\r\n\$4\r\nbebe\r\n" 2}
+    }
+
+    r flushdb
+}