[Java Client] Send CloseConsumer on client timeout

pulsar-broker/src/test/java/org/apache/pulsar/client/api/ClientErrorsTest.java

@@ -240,7 +240,7 @@ private void producerCreatedThenFailsRetryTimeout(String topic) throws Exception
         });
 
         // Create producer should succeed then upon closure, it should reattempt creation. The first request will
-        // timeout, which triggers CloseProducer. The client might send send the third Producer command before the
+        // time out, which triggers CloseProducer. The client might send the third Producer command before the
         // below assertion, so we pass with 2 or 3.
         client.newProducer().topic(topic).create();
         Awaitility.await().until(() -> closeProducerCounter.get() == 1);
@@ -249,6 +249,51 @@ private void producerCreatedThenFailsRetryTimeout(String topic) throws Exception
         mockBrokerService.resetHandleCloseProducer();
     }
 
+    @Test
+    public void testCreatedConsumerSendsCloseConsumerAfterTimeout() throws Exception {
+        consumerCreatedThenFailsRetryTimeout("persistent://prop/use/ns/t1");
+    }
+
+    @Test
+    public void testCreatedPartitionedConsumerSendsCloseConsumerAfterTimeout() throws Exception {
+        consumerCreatedThenFailsRetryTimeout("persistent://prop/use/ns/part-t1");
+    }
+
+    private void consumerCreatedThenFailsRetryTimeout(String topic) throws Exception {
+        @Cleanup
+        PulsarClient client = PulsarClient.builder().serviceUrl(mockBrokerService.getBrokerAddress())
+                .operationTimeout(1, TimeUnit.SECONDS).build();
+        final AtomicInteger subscribeCounter = new AtomicInteger(0);
+        final AtomicInteger closeConsumerCounter = new AtomicInteger(0);
+
+        mockBrokerService.setHandleSubscribe((ctx, subscribe) -> {
+            int subscribeCount = subscribeCounter.incrementAndGet();
+            if (subscribeCount == 1) {
+                ctx.writeAndFlush(Commands.newSuccess(subscribe.getRequestId()));
+                // Trigger reconnect
+                ctx.writeAndFlush(Commands.newCloseConsumer(subscribe.getConsumerId(), -1));
+            } else if (subscribeCount != 2) {
+                // Respond to subsequent requests to prevent timeouts
+                ctx.writeAndFlush(Commands.newSuccess(subscribe.getRequestId()));
+            }
+            // Don't respond to the second Subscribe command to ensure timeout
+        });
+
+        mockBrokerService.setHandleCloseConsumer((ctx, closeConsumer) -> {
+            closeConsumerCounter.incrementAndGet();
+            ctx.writeAndFlush(Commands.newSuccess(closeConsumer.getRequestId()));
+        });
+
+        // Create consumer (subscribe) should succeed then upon closure, it should reattempt creation. The first
+        // request will time out, which triggers CloseConsumer. The client might send the third Subscribe command before
+        // the below assertion, so we pass with 2 or 3.
+        client.newConsumer().topic(topic).subscriptionName("test").subscribe();
+        Awaitility.await().until(() -> closeConsumerCounter.get() == 1);
+        Awaitility.await().until(() -> subscribeCounter.get() == 2 || subscribeCounter.get() == 3);
+        mockBrokerService.resetHandleSubscribe();
+        mockBrokerService.resetHandleCloseConsumer();
+    }
+
     @Test
     public void testProducerFailDoesNotFailOtherProducer() throws Exception {
         producerFailDoesNotFailOtherProducer("persistent://prop/use/ns/t1", "persistent://prop/use/ns/t2");

pulsar-client/src/main/java/org/apache/pulsar/client/impl/ConsumerImpl.java

@@ -901,6 +901,15 @@ public void connectionOpened(final ClientCnx cnx) {
                 log.warn("[{}][{}] Failed to subscribe to topic on {}", topic,
                         subscription, cnx.channel().remoteAddress());
 
+                if (e.getCause() instanceof PulsarClientException.TimeoutException) {
+                    // Creating the consumer has timed out. We need to ensure the broker closes the consumer
+                    // in case it was indeed created, otherwise it might prevent new create consumer operation,
+                    // since we are not necessarily closing the connection.
+                    long closeRequestId = client.newRequestId();
+                    ByteBuf cmd = Commands.newCloseConsumer(consumerId, closeRequestId);
+                    cnx.sendRequestWithId(cmd, closeRequestId);
+                }
+
                 if (e.getCause() instanceof PulsarClientException
                         && PulsarClientException.isRetriableError(e.getCause())
                         && System.currentTimeMillis() < SUBSCRIBE_DEADLINE_UPDATER.get(ConsumerImpl.this)) {

site2/docs/developing-binary-protocol.md

@@ -333,6 +333,10 @@ Before creating or connecting a consumer, you need to perform [topic lookup](#to
 
 :::
 
+If the client does not receive a response indicating consumer creation success or failure,
+the client should first send a command to close the original consumer before sending a
+command to re-attempt consumer creation.
+
 #### Flow control
 
 After the consumer is ready, the client needs to *give permission* to the
@@ -479,6 +483,11 @@ This command can be sent by either producer or broker.
 
 This command behaves the same as [`CloseProducer`](#command-closeproducer)
 
+If the client does not receive a response to a `Subscribe` command within a timeout,
+the client must first send a `CloseConsumer` command before sending another
+`Subscribe` command. The client does not need to await a response to the `CloseConsumer`
+command before sending the next `Subscribe` command.
+
 ##### Command RedeliverUnacknowledgedMessages
 
 A consumer can ask the broker to redeliver some or all of the pending messages