com.google.cloud.spring.pubsub.core.subscriber

Class PubSubSubscriberTemplate

java.lang.Object

com.google.cloud.spring.pubsub.core.subscriber.PubSubSubscriberTemplate

All Implemented Interfaces:

PubSubSubscriberOperations, org.springframework.beans.factory.DisposableBean

public class PubSubSubscriberTemplate
extends Object
implements PubSubSubscriberOperations, org.springframework.beans.factory.DisposableBean

Default implementation of PubSubSubscriberOperations.

The main Google Cloud Pub/Sub integration component for consuming messages from subscriptions asynchronously or by pulling. A custom Executor can be injected to control per-subscription batch parallelization in acknowledgement and deadline operations. By default, this is a single thread executor, created per instance of the PubSubSubscriberTemplate. A custom Executor can be injected to control the threads that process the responses of the asynchronous pull callback operations. By default, this is executed on the same thread that executes the callback.

Since:

1.1

Author:

Vinicius Carvalho, João André Martins, Mike Eltsufin, Chengyuan Zhao, Doug Hoard, Elena Felder, Maurice Zeijen

Constructor Summary

Constructors

Constructor and Description
PubSubSubscriberTemplate(SubscriberFactory subscriberFactory) Default PubSubSubscriberTemplate constructor.

Method Summary

Modifier and Type	Method and Description
org.springframework.util.concurrent.ListenableFuture<Void>	ack(Collection<? extends AcknowledgeablePubsubMessage> acknowledgeablePubsubMessages) Acknowledge messages in per-subscription batches.
void	destroy() Destroys the default executor, regardless of whether it was used.
PubSubMessageConverter	getMessageConverter() Get the converter used to convert a message payload to the desired type.
SubscriberFactory	getSubscriberFactory()
org.springframework.util.concurrent.ListenableFuture<Void>	modifyAckDeadline(Collection<? extends AcknowledgeablePubsubMessage> acknowledgeablePubsubMessages, int ackDeadlineSeconds) Modify multiple messages' ack deadline in per-subscription batches.
org.springframework.util.concurrent.ListenableFuture<Void>	nack(Collection<? extends AcknowledgeablePubsubMessage> acknowledgeablePubsubMessages) Nack messages in per-subscription batches.
List<AcknowledgeablePubsubMessage>	pull(String subscription, Integer maxMessages, Boolean returnImmediately) Pull a number of messages from a Google Cloud Pub/Sub subscription.
List<com.google.pubsub.v1.PubsubMessage>	pullAndAck(String subscription, Integer maxMessages, Boolean returnImmediately) Pull and auto-acknowledge a number of messages from a Google Cloud Pub/Sub subscription.
org.springframework.util.concurrent.ListenableFuture<List<com.google.pubsub.v1.PubsubMessage>>	pullAndAckAsync(String subscription, Integer maxMessages, Boolean returnImmediately) Asynchronously pull and auto-acknowledge a number of messages from a Google Cloud Pub/Sub subscription.
<T> List<ConvertedAcknowledgeablePubsubMessage<T>>	pullAndConvert(String subscription, Integer maxMessages, Boolean returnImmediately, Class<T> payloadType) Pull a number of messages from a Google Cloud Pub/Sub subscription and convert them to Spring messages with the desired payload type.
<T> org.springframework.util.concurrent.ListenableFuture<List<ConvertedAcknowledgeablePubsubMessage<T>>>	pullAndConvertAsync(String subscription, Integer maxMessages, Boolean returnImmediately, Class<T> payloadType) Asynchronously pull a number of messages from a Google Cloud Pub/Sub subscription and convert them to Spring messages with the desired payload type.
org.springframework.util.concurrent.ListenableFuture<List<AcknowledgeablePubsubMessage>>	pullAsync(String subscription, Integer maxMessages, Boolean returnImmediately) Asynchronously pull a number of messages from a Google Cloud Pub/Sub subscription.
com.google.pubsub.v1.PubsubMessage	pullNext(String subscription) Pull and auto-acknowledge a message from a Google Cloud Pub/Sub subscription.
org.springframework.util.concurrent.ListenableFuture<com.google.pubsub.v1.PubsubMessage>	pullNextAsync(String subscription) Asynchronously pull and auto-acknowledge a message from a Google Cloud Pub/Sub subscription.
void	setAckExecutor(Executor ackExecutor) Sets the Executor to control per-subscription batch parallelization in acknowledgement and deadline operations.
void	setAsyncPullExecutor(Executor asyncPullExecutor) Set a custom Executor to control the threads that process the responses of the asynchronous pull callback operations.
void	setMessageConverter(PubSubMessageConverter pubSubMessageConverter) Set the converter used to convert a message payload to the desired type.
Subscriber	subscribe(String subscription, Consumer<BasicAcknowledgeablePubsubMessage> messageConsumer) Add a callback method to an existing subscription.
<T> Subscriber	subscribeAndConvert(String subscription, Consumer<ConvertedBasicAcknowledgeablePubsubMessage<T>> messageConsumer, Class<T> payloadType) Add a callback method to an existing subscription that receives Pub/Sub messages converted to the requested payload type.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PubSubSubscriberTemplate

public PubSubSubscriberTemplate(SubscriberFactory subscriberFactory)

Default PubSubSubscriberTemplate constructor.

Parameters:

subscriberFactory - the Subscriber factory to subscribe to subscriptions or pull messages.

Method Detail

getMessageConverter

public PubSubMessageConverter getMessageConverter()

Get the converter used to convert a message payload to the desired type.

Returns:

the currently used converter

setMessageConverter

public void setMessageConverter(PubSubMessageConverter pubSubMessageConverter)

Set the converter used to convert a message payload to the desired type.

Parameters:

pubSubMessageConverter - the converter to set

setAckExecutor

public void setAckExecutor(Executor ackExecutor)

Sets the Executor to control per-subscription batch parallelization in acknowledgement and deadline operations.

Parameters:

ackExecutor - the executor to set

setAsyncPullExecutor

public void setAsyncPullExecutor(Executor asyncPullExecutor)

Set a custom Executor to control the threads that process the responses of the asynchronous pull callback operations.

Parameters:

asyncPullExecutor - the executor to set

subscribe

public Subscriber subscribe(String subscription,
                            Consumer<BasicAcknowledgeablePubsubMessage> messageConsumer)

Description copied from interface: PubSubSubscriberOperations

Add a callback method to an existing subscription.

The created Subscriber is returned so it can be stopped.

Specified by:

subscribe in interface PubSubSubscriberOperations

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

messageConsumer - the callback method triggered when new messages arrive

Returns:

subscriber listening to new messages

subscribeAndConvert

public <T> Subscriber subscribeAndConvert(String subscription,
                                          Consumer<ConvertedBasicAcknowledgeablePubsubMessage<T>> messageConsumer,
                                          Class<T> payloadType)

Description copied from interface: PubSubSubscriberOperations

Add a callback method to an existing subscription that receives Pub/Sub messages converted to the requested payload type.

The created Subscriber is returned so it can be stopped.

Specified by:

subscribeAndConvert in interface PubSubSubscriberOperations

Type Parameters:

T - the type of the payload

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

messageConsumer - the callback method triggered when new messages arrive

payloadType - the type to which the payload of the Pub/Sub message should be converted

Returns:

subscriber listening to new messages

pull

public List<AcknowledgeablePubsubMessage> pull(String subscription,
                                               Integer maxMessages,
                                               Boolean returnImmediately)

Description copied from interface: PubSubSubscriberOperations

Pull a number of messages from a Google Cloud Pub/Sub subscription.

Specified by:

pull in interface PubSubSubscriberOperations

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

maxMessages - the maximum number of pulled messages. If this value is null then up to Integer.MAX_VALUE messages will be requested.

returnImmediately - returns immediately even if subscription doesn't contain enough messages to satisfy maxMessages. Setting this parameter to true is not recommended as it may result in long delays in message delivery.

Returns:

the list of received acknowledgeable messages

pullAsync

public org.springframework.util.concurrent.ListenableFuture<List<AcknowledgeablePubsubMessage>> pullAsync(String subscription,
                                                                                                          Integer maxMessages,
                                                                                                          Boolean returnImmediately)

Description copied from interface: PubSubSubscriberOperations

Asynchronously pull a number of messages from a Google Cloud Pub/Sub subscription.

Specified by:

pullAsync in interface PubSubSubscriberOperations

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

maxMessages - the maximum number of pulled messages. If this value is null then up to Integer.MAX_VALUE messages will be requested.

returnImmediately - returns immediately even if subscription doesn't contain enough messages to satisfy maxMessages. Setting this parameter to true is not recommended as it may result in long delays in message delivery.

Returns:

the ListenableFuture for the asynchronous execution, returning the list of received acknowledgeable messages

pullAndConvert

public <T> List<ConvertedAcknowledgeablePubsubMessage<T>> pullAndConvert(String subscription,
                                                                         Integer maxMessages,
                                                                         Boolean returnImmediately,
                                                                         Class<T> payloadType)

Description copied from interface: PubSubSubscriberOperations

Pull a number of messages from a Google Cloud Pub/Sub subscription and convert them to Spring messages with the desired payload type.

Specified by:

pullAndConvert in interface PubSubSubscriberOperations

Type Parameters:

T - the type of the payload

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

maxMessages - the maximum number of pulled messages. If this value is null then up to Integer.MAX_VALUE messages will be requested.

returnImmediately - returns immediately even if subscription doesn't contain enough messages to satisfy maxMessages. Setting this parameter to true is not recommended as it may result in long delays in message delivery.

payloadType - the type to which the payload of the Pub/Sub messages should be converted

Returns:

the list of received acknowledgeable messages

pullAndConvertAsync

public <T> org.springframework.util.concurrent.ListenableFuture<List<ConvertedAcknowledgeablePubsubMessage<T>>> pullAndConvertAsync(String subscription,
                                                                                                                                    Integer maxMessages,
                                                                                                                                    Boolean returnImmediately,
                                                                                                                                    Class<T> payloadType)

Description copied from interface: PubSubSubscriberOperations

Asynchronously pull a number of messages from a Google Cloud Pub/Sub subscription and convert them to Spring messages with the desired payload type.

Specified by:

pullAndConvertAsync in interface PubSubSubscriberOperations

Type Parameters:

T - the type of the payload

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

maxMessages - the maximum number of pulled messages. If this value is null then up to Integer.MAX_VALUE messages will be requested.

returnImmediately - returns immediately even if subscription doesn't contain enough messages to satisfy maxMessages. Setting this parameter to true is not recommended as it may result in long delays in message delivery.

payloadType - the type to which the payload of the Pub/Sub messages should be converted

Returns:

the ListenableFuture for the asynchronous execution, returning the list of received acknowledgeable messages

pullAndAck

public List<com.google.pubsub.v1.PubsubMessage> pullAndAck(String subscription,
                                                           Integer maxMessages,
                                                           Boolean returnImmediately)

Description copied from interface: PubSubSubscriberOperations

Pull and auto-acknowledge a number of messages from a Google Cloud Pub/Sub subscription.

Specified by:

pullAndAck in interface PubSubSubscriberOperations

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

maxMessages - the maximum number of pulled messages. If this value is null then up to Integer.MAX_VALUE messages will be requested.

returnImmediately - returns immediately even if subscription doesn't contain enough messages to satisfy maxMessages. Setting this parameter to true is not recommended as it may result in long delays in message delivery.

Returns:

the list of received messages

pullAndAckAsync

public org.springframework.util.concurrent.ListenableFuture<List<com.google.pubsub.v1.PubsubMessage>> pullAndAckAsync(String subscription,
                                                                                                                      Integer maxMessages,
                                                                                                                      Boolean returnImmediately)

Description copied from interface: PubSubSubscriberOperations

Asynchronously pull and auto-acknowledge a number of messages from a Google Cloud Pub/Sub subscription.

Specified by:

pullAndAckAsync in interface PubSubSubscriberOperations

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

maxMessages - the maximum number of pulled messages. If this value is null then up to Integer.MAX_VALUE messages will be requested.

returnImmediately - returns immediately even if subscription doesn't contain enough messages to satisfy maxMessages. Setting this parameter to true is not recommended as it may result in long delays in message delivery.

Returns:

the ListenableFuture for the asynchronous execution, returning the list of received acknowledgeable messages

pullNext

public com.google.pubsub.v1.PubsubMessage pullNext(String subscription)

Description copied from interface: PubSubSubscriberOperations

Pull and auto-acknowledge a message from a Google Cloud Pub/Sub subscription.

Specified by:

pullNext in interface PubSubSubscriberOperations

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

Returns:

a received message, or null if none exists in the subscription

pullNextAsync

public org.springframework.util.concurrent.ListenableFuture<com.google.pubsub.v1.PubsubMessage> pullNextAsync(String subscription)

Description copied from interface: PubSubSubscriberOperations

Asynchronously pull and auto-acknowledge a message from a Google Cloud Pub/Sub subscription.

Specified by:

pullNextAsync in interface PubSubSubscriberOperations

Parameters:

subscription - canonical subscription name, e.g., "subscriptionName", or the fully-qualified subscription name in the projects/<project_name>/subscriptions/<subscription_name> format

Returns:

the ListenableFuture for the asynchronous execution, returning a received message, or null if none exists in the subscription

getSubscriberFactory

public SubscriberFactory getSubscriberFactory()

ack

public org.springframework.util.concurrent.ListenableFuture<Void> ack(Collection<? extends AcknowledgeablePubsubMessage> acknowledgeablePubsubMessages)

Acknowledge messages in per-subscription batches. If any batch fails, the returned Future is marked as failed. If multiple batches fail, the returned Future will contain whichever exception was detected first.

Specified by:

ack in interface PubSubSubscriberOperations

Parameters:

acknowledgeablePubsubMessages - messages, potentially from different subscriptions.

Returns:

ListenableFuture indicating overall success or failure.

nack

public org.springframework.util.concurrent.ListenableFuture<Void> nack(Collection<? extends AcknowledgeablePubsubMessage> acknowledgeablePubsubMessages)

Nack messages in per-subscription batches. If any batch fails, the returned Future is marked as failed. If multiple batches fail, the returned Future will contain whichever exception was detected first.

Specified by:

nack in interface PubSubSubscriberOperations

Parameters:

acknowledgeablePubsubMessages - messages, potentially from different subscriptions.

Returns:

ListenableFuture indicating overall success or failure.

modifyAckDeadline

public org.springframework.util.concurrent.ListenableFuture<Void> modifyAckDeadline(Collection<? extends AcknowledgeablePubsubMessage> acknowledgeablePubsubMessages,
                                                                                    int ackDeadlineSeconds)

Modify multiple messages' ack deadline in per-subscription batches. If any batch fails, the returned Future is marked as failed. If multiple batches fail, the returned Future will contain whichever exception was detected first.

Specified by:

modifyAckDeadline in interface PubSubSubscriberOperations

Parameters:

acknowledgeablePubsubMessages - messages, potentially from different subscriptions.

ackDeadlineSeconds - the new ack deadline in seconds. A deadline of 0 effectively nacks the messages.

Returns:

ListenableFuture indicating overall success or failure.

destroy

public void destroy()

Destroys the default executor, regardless of whether it was used.

Specified by:

destroy in interface org.springframework.beans.factory.DisposableBean