Added AOF rewrite support for functions. (#10141)

Function PR was merged without AOF rw support because we thought this feature was going
to be removed on Redis 7.

Tests was added on aofrw.tcl
Other existing aofrw tests where slow due to unwanted rdb-key-save-delay

Co-authored-by: Oran Agra <oran@redislabs.com>

src/aof.c

@@ -2102,6 +2102,35 @@ int rewriteModuleObject(rio *r, robj *key, robj *o, int dbid) {
     return io.error ? 0 : 1;
 }
 
+static int rewriteFunctions(rio *aof) {
+    dict *functions = functionsLibGet();
+    dictIterator *iter = dictGetIterator(functions);
+    dictEntry *entry = NULL;
+    while ((entry = dictNext(iter))) {
+        functionLibInfo *li = dictGetVal(entry);
+        if (li->desc) {
+            if (rioWrite(aof, "*7\r\n", 4) == 0) goto werr;
+        } else {
+            if (rioWrite(aof, "*5\r\n", 4) == 0) goto werr;
+        }
+        char fucntion_load[] = "$8\r\nFUNCTION\r\n$4\r\nLOAD\r\n";
+        if (rioWrite(aof, fucntion_load, sizeof(fucntion_load) - 1) == 0) goto werr;
+        if (rioWriteBulkString(aof, li->ei->name, sdslen(li->ei->name)) == 0) goto werr;
+        if (rioWriteBulkString(aof, li->name, sdslen(li->name)) == 0) goto werr;
+        if (li->desc) {
+            if (rioWriteBulkString(aof, "description", 11) == 0) goto werr;
+            if (rioWriteBulkString(aof, li->desc, sdslen(li->desc)) == 0) goto werr;
+        }
+        if (rioWriteBulkString(aof, li->code, sdslen(li->code)) == 0) goto werr;
+    }
+    dictReleaseIterator(iter);
+    return 1;
+
+werr:
+    dictReleaseIterator(iter);
+    return 0;
+}
+
 int rewriteAppendOnlyFileRio(rio *aof) {
     dictIterator *di = NULL;
     dictEntry *de;
@@ -2116,6 +2145,8 @@ int rewriteAppendOnlyFileRio(rio *aof) {
         sdsfree(ts);
     }
 
+    if (rewriteFunctions(aof) == 0) goto werr;
+
     for (j = 0; j < server.dbnum; j++) {
         char selectcmd[] = "*2\r\n$6\r\nSELECT\r\n";
         redisDb *db = server.db+j;

tests/unit/aofrw.tcl

@@ -74,6 +74,7 @@ start_server {tags {"aofrw external:skip"} overrides {aof-use-rdb-preamble no}}
         } else {
             fail "Can't find 'Killing AOF child' into recent logs"
         }
+        r config set rdb-key-save-delay 0
     }
 
     foreach d {string int} {
@@ -182,6 +183,19 @@ start_server {tags {"aofrw external:skip"} overrides {aof-use-rdb-preamble no}}
         }
     }
 
+    test "AOF rewrite functions" {
+        r flushall
+        r FUNCTION LOAD LUA test DESCRIPTION {desc} {
+            redis.register_function('test', function() return 1 end)
+        }
+        r bgrewriteaof
+        waitForBgrewriteaof r
+        r function flush
+        r debug loadaof
+        assert_equal [r fcall test 0] 1
+        r FUNCTION LIST
+    } {{library_name test engine LUA description desc functions {{name test description {} flags {}}}}}
+
     test {BGREWRITEAOF is delayed if BGSAVE is in progress} {
         r flushall
         r set k v