com.google.cloud.pubsub.v1

Class Subscriber.Builder

java.lang.Object

com.google.cloud.pubsub.v1.Subscriber.Builder

Enclosing class:

Subscriber

public static final class Subscriber.Builder
extends Object

Builder of Subscribers.

Method Summary

Modifier and Type	Method and Description
Subscriber	build()
Subscriber.Builder	setChannelProvider(TransportChannelProvider channelProvider) ChannelProvider to use to create Channels, which must point at Cloud Pub/Sub endpoint.
Subscriber.Builder	setCredentialsProvider(CredentialsProvider credentialsProvider) CredentialsProvider to use to create Credentials to authenticate calls.
Subscriber.Builder	setExecutorProvider(ExecutorProvider executorProvider) Gives the ability to set a custom executor.
Subscriber.Builder	setFlowControlSettings(FlowControlSettings flowControlSettings) Sets the flow control settings.
Subscriber.Builder	setHeaderProvider(HeaderProvider headerProvider) Sets the static header provider.
Subscriber.Builder	setMaxAckExtensionPeriod(org.threeten.bp.Duration maxAckExtensionPeriod) Set the maximum period a message ack deadline will be extended.
Subscriber.Builder	setParallelPullCount(int parallelPullCount) Sets the number of pullers used to pull messages from the subscription.
Subscriber.Builder	setSystemExecutorProvider(ExecutorProvider executorProvider) Gives the ability to set a custom executor for managing lease extensions.

Methods inherited from class java.lang.Object

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

Method Detail

setChannelProvider

public Subscriber.Builder setChannelProvider(TransportChannelProvider channelProvider)

ChannelProvider to use to create Channels, which must point at Cloud Pub/Sub endpoint.

For performance, this client benefits from having multiple channels open at once. Users are encouraged to provide instances of ChannelProvider that creates new channels instead of returning pre-initialized ones.

setHeaderProvider

@BetaApi
public Subscriber.Builder setHeaderProvider(HeaderProvider headerProvider)

Sets the static header provider. The header provider will be called during client construction only once. The headers returned by the provider will be cached and supplied as is for each request issued by the constructed client. Some reserved headers can be overridden (e.g. Content-Type) or merged with the default value (e.g. User-Agent) by the underlying transport layer.

Parameters:

headerProvider - the header provider

Returns:

the builder

setFlowControlSettings

public Subscriber.Builder setFlowControlSettings(FlowControlSettings flowControlSettings)

Sets the flow control settings.

In the example below, the Subscriber will make sure that

• there are at most ten thousand outstanding messages, and
• the combined size of outstanding messages does not exceed 1GB.

"Outstanding messages" here means the messages that have already been given to MessageReceiver but not yet acked() or nacked().

 FlowControlSettings flowControlSettings =
  FlowControlSettings.newBuilder()
      .setMaxOutstandingElementCount(10_000L)
      .setMaxOutstandingRequestBytes(1_000_000_000L)
      .build();
 Subscriber subscriber =
     Subscriber.newBuilder(subscriptionName, receiver)
         .setFlowControlSettings(flowControlSettings)
         .build();
 

setMaxAckExtensionPeriod

public Subscriber.Builder setMaxAckExtensionPeriod(org.threeten.bp.Duration maxAckExtensionPeriod)

Set the maximum period a message ack deadline will be extended. Defaults to one hour.

It is recommended to set this value to a reasonable upper bound of the subscriber time to process any message. This maximum period avoids messages to be locked by a subscriber in cases when the ack reply is lost.

A zero duration effectively disables auto deadline extensions.

setExecutorProvider

public Subscriber.Builder setExecutorProvider(ExecutorProvider executorProvider)

Gives the ability to set a custom executor. ExecutorProvider.getExecutor() will be called parallelPullCount times.

setCredentialsProvider

public Subscriber.Builder setCredentialsProvider(CredentialsProvider credentialsProvider)

CredentialsProvider to use to create Credentials to authenticate calls.

setSystemExecutorProvider

public Subscriber.Builder setSystemExecutorProvider(ExecutorProvider executorProvider)

Gives the ability to set a custom executor for managing lease extensions. If none is provided a shared one will be used by all Subscriber instances.

setParallelPullCount

public Subscriber.Builder setParallelPullCount(int parallelPullCount)

Sets the number of pullers used to pull messages from the subscription. Defaults to one.

build

public Subscriber build()