[FIXED] JetStream: auto-ack callback ack handling

examples/js-sub.c

@@ -38,7 +38,7 @@ onMsg(natsConnection *nc, natsSubscription *sub, natsMsg *msg, void *closure)
     if (++count == total)
         elapsed = nats_Now() - start;
 
-    natsMsg_Ack(msg, NULL);
+    // Since this is auto-ack callback, we don't need to ack here.
     natsMsg_Destroy(msg);
 }
 

src/js.c

@@ -1000,35 +1000,15 @@ static void
 _autoAckCB(natsConnection *nc, natsSubscription *sub, natsMsg *msg, void *closure)
 {
     jsSub   *jsi = (jsSub*) closure;
-    char    _reply[256];
-    char    *reply = NULL;
-    bool    frply  = false;
 
-    if (msg->reply != NULL)
-    {
-        if (strlen(msg->reply) < sizeof(_reply))
-        {
-            snprintf(_reply, sizeof(_reply), "%s", msg->reply);
-            reply = _reply;
-        }
-        else
-        {
-            reply = NATS_STRDUP(msg->reply);
-            frply = (reply != NULL ? true : false);
-        }
-    }
+    natsMsg_setNoDestroy(msg);
 
     // Invoke user callback
     (jsi->usrCb)(nc, sub, msg, jsi->usrCbClosure);
 
-    // Ack the message (unless we got a failure copying the reply subject)
-    if (reply == NULL)
-        return;
-
-    natsConnection_PublishString(nc, reply, jsAckAck);
-
-    if (frply)
-        NATS_FREE(reply);
+    natsMsg_Ack(msg, &(jsi->js->opts));
+    natsMsg_clearNoDestroy(msg);
+    natsMsg_Destroy(msg);
 }
 
 natsStatus

src/msg.c

@@ -680,6 +680,9 @@ natsMsg_Destroy(natsMsg *msg)
     if (msg == NULL)
         return;
 
+    if (natsMsg_isNoDestroy(msg))
+        return;
+
     if (natsGC_collect((natsGCItem *) msg))
         return;
 

src/msg.h

@@ -37,6 +37,10 @@
 #define natsMsg_isAcked(m)          (((m)->flags &   (1 << 1)) != 0)
 #define natsMsg_clearAcked(m)       ((m)->flags  &= ~(1 << 1))
 
+#define natsMsg_setNoDestroy(m)     ((m)->flags  |=  (1 << 2))
+#define natsMsg_isNoDestroy(m)      (((m)->flags &   (1 << 2)) != 0)
+#define natsMsg_clearNoDestroy(m)   ((m)->flags  &= ~(1 << 2))
+
 struct __natsMsg
 {
     natsGCItem          gc;

test/test.c

@@ -23402,6 +23402,17 @@ _jsMsgHandler(natsConnection *nc, natsSubscription *sub, natsMsg *msg, void *clo
     args->sum++;
     if (args->control == 1)
         natsMsg_Ack(msg, NULL);
+    else if (args->control == 3)
+    {
+        if (args->sum == 1)
+            natsMsg_Nak(msg, NULL);
+        else
+        {
+            while (!args->done)
+                natsCondition_Wait(args->c, args->m);
+            args->msgReceived = true;
+        }
+    }
     if ((args->control != 2) || (args->sum == args->results[0]))
         natsCondition_Broadcast(args->c);
     natsMutex_Unlock(args->m);
@@ -23628,6 +23639,54 @@ test_JetStreamSubscribe(void)
     natsSubscription_Destroy(sub);
     sub = NULL;
 
+    test("Create sub with auto-ack: ");
+    natsMutex_Lock(args.m);
+    args.control = 3;
+    args.sum = 0;
+    natsMutex_Unlock(args.m);
+    jsSubOptions_Init(&so);
+    so.Stream = "TEST";
+    so.Config.DeliverPolicy = js_DeliverLast;
+    s = js_Subscribe(&sub, js, "foo", _jsMsgHandler, (void*)&args, NULL, &so, &jerr);
+    testCond((s == NATS_OK) && (sub != NULL) && (jerr == 0));
+
+    test("Check msgs received: ");
+    natsMutex_Lock(args.m);
+    while ((s != NATS_TIMEOUT) && (args.sum < 1))
+        s = natsCondition_TimedWait(args.c, args.m, 2000);
+    natsMutex_Unlock(args.m);
+    testCond(s == NATS_OK);
+
+    test("Check NAck sent: ");
+    s = natsSubscription_NextMsg(&ack, ackSub, 1000);
+    testCond(s == NATS_OK);
+    natsMsg_Destroy(ack);
+    ack = NULL;
+
+    test("Check no auto-ack: ");
+    s = natsSubscription_NextMsg(&ack, ackSub, 100);
+    testCond((s == NATS_TIMEOUT) && (ack == NULL));
+    nats_clearLastError();
+    s = NATS_OK;
+
+    natsMutex_Lock(args.m);
+    args.done = true;
+    natsCondition_Broadcast(args.c);
+    while ((s != NATS_TIMEOUT) && !args.msgReceived)
+        s = natsCondition_TimedWait(args.c, args.m, 1000);
+    args.done = false;
+    args.msgReceived = false;
+    natsMutex_Unlock(args.m);
+
+    test("Check auto-ack sent: ");
+    s = natsSubscription_NextMsg(&ack, ackSub, 1000);
+    testCond(s == NATS_OK);
+    natsMsg_Destroy(ack);
+    ack = NULL;
+
+    natsSubscription_Destroy(sub);
+    sub = NULL;
+
     test("Create queue sub: ");
     natsMutex_Lock(args.m);
     args.control = 0;