[Broker] Check allowAutoSubscriptionCreation when creating init sub (…

…apache#14458)

Master Issue: apache#13408 

### Motivation

In apache#13355, we added support for creating initial subscription when creating the producer. But the broker didn't check if the subscription can be created automatically. The initial subscription will be created even if the `allowAutoSubscriptionCreation` is disabled.

pulsar-broker/src/main/java/org/apache/pulsar/broker/service/ServerCnx.java

@@ -1273,6 +1273,20 @@ protected void handleProducer(final CommandProducer cmdProducer) {
                             if (!Strings.isNullOrEmpty(initialSubscriptionName)
                                     && topic.isPersistent()
                                     && !topic.getSubscriptions().containsKey(initialSubscriptionName)) {
+                                if (!this.getBrokerService().isAllowAutoSubscriptionCreation(topicName)) {
+                                    String msg =
+                                            "Could not create the initial subscription due to the auto subscription "
+                                                    + "creation is not allowed.";
+                                    if (producerFuture.completeExceptionally(
+                                            new BrokerServiceException.NotAllowedException(msg))) {
+                                        log.warn("[{}] {} initialSubscriptionName: {}, topic: {}",
+                                                remoteAddress, msg, initialSubscriptionName, topicName);
+                                        commandSender.sendErrorResponse(requestId,
+                                                ServerError.NotAllowedError, msg);
+                                    }
+                                    producers.remove(producerId, producerFuture);
+                                    return;
+                                }
                                 createInitSubFuture =
                                         topic.createSubscription(initialSubscriptionName, InitialPosition.Earliest,
                                                 false);

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

@@ -18,6 +18,7 @@
  */
 package org.apache.pulsar.client.api;
 
+import static org.testng.Assert.fail;
 import org.apache.pulsar.client.admin.PulsarAdminException;
 import org.apache.pulsar.client.impl.ProducerBuilderImpl;
 import org.apache.pulsar.client.impl.ProducerImpl;
@@ -167,4 +168,27 @@ public void testCreateInitialSubscriptionWhenExisting() throws PulsarClientExcep
 
         Assert.assertTrue(admin.topics().getSubscriptions(topic.toString()).contains(initialSubscriptionName));
     }
+
+    @Test
+    public void testInitialSubscriptionCreationWithAutoCreationDisable()
+            throws PulsarAdminException, PulsarClientException {
+        pulsar.getConfiguration().setAllowAutoSubscriptionCreation(false);
+
+        final TopicName topic =
+                TopicName.get("persistent", "public", "default",
+                        "testInitialSubscriptionCreationWithAutoCreationDisable");
+        final String initialSubscriptionName = "init-sub";
+        admin.topics().createNonPartitionedTopic(topic.toString());
+        try {
+            Producer<byte[]> producer = ((ProducerBuilderImpl<byte[]>) pulsarClient.newProducer())
+                    .initialSubscriptionName(initialSubscriptionName)
+                    .topic(topic.toString())
+                    .create();
+            fail("Should not pass");
+        } catch (PulsarClientException.NotAllowedException exception) {
+            // ok
+        }
+
+        Assert.assertFalse(admin.topics().getSubscriptions(topic.toString()).contains(initialSubscriptionName));
+    }
 }

pulsar-client-api/src/main/java/org/apache/pulsar/client/api/DeadLetterPolicy.java

@@ -52,6 +52,8 @@ public class DeadLetterPolicy {
     /**
      * Name of the initial subscription name of the dead letter topic.
      * If this field is not set, the initial subscription for the dead letter topic will not be created.
+     * If this field is set but the broker's `allowAutoSubscriptionCreation` is disabled, the DLQ producer will fail
+     * to be created.
      */
     private String initialSubscriptionName;
 }

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

@@ -328,7 +328,9 @@ public ProducerBuilder<T> enableLazyStartPartitionedProducers(boolean lazyStartP
     /**
      * Use this config to automatically create an initial subscription when creating the topic.
      * If this field is not set, the initial subscription will not be created.
-     * This method is limited to internal use
+     * If this field is set but the broker's `allowAutoSubscriptionCreation` is disabled, the producer will fail to
+     * be created.
+     * This method is limited to internal use. This method will only be used when the consumer creates the dlq producer.
      *
      * @param initialSubscriptionName Name of the initial subscription of the topic.
      * @return the producer builder implementation instance

pulsar-common/src/main/proto/PulsarApi.proto

@@ -497,6 +497,8 @@ message CommandProducer {
 
     // Name of the initial subscription of the topic.
     // If this field is not set, the initial subscription will not be created.
+    // If this field is set but the broker's `allowAutoSubscriptionCreation`
+    // is disabled, the producer will fail to be created.
     optional string initial_subscription_name = 13;
 }
 

site2/docs/concepts-messaging.md

@@ -317,7 +317,7 @@ Consumer<byte[]> consumer = pulsarClient.newConsumer(Schema.BYTES)
                 
 ```
 
-By default, there is no subscription during a DLQ topic creation. Without a just-in-time subscription to the DLQ topic, you may lose messages. To automatically create an initial subscription for the DLQ, you can specify the `initialSubscriptionName` parameter.
+By default, there is no subscription during a DLQ topic creation. Without a just-in-time subscription to the DLQ topic, you may lose messages. To automatically create an initial subscription for the DLQ, you can specify the `initialSubscriptionName` parameter. If this parameter is set but the broker's `allowAutoSubscriptionCreation` is disabled, the DLQ producer will fail to be created.
 
 ```java
 Consumer<byte[]> consumer = pulsarClient.newConsumer(Schema.BYTES)