com.snowplowanalytics.snowplow.tracker.emitter

Class BatchEmitter

java.lang.Object

com.snowplowanalytics.snowplow.tracker.emitter.BatchEmitter

All Implemented Interfaces:

Emitter, java.io.Closeable, java.lang.AutoCloseable

public class BatchEmitter
extends java.lang.Object
implements Emitter, java.io.Closeable

An emitter that emits a batch of events in a single HTTP request. It uses the POST method of the underlying HTTP adapter. When a new event (TrackerPayload) is received and added to the buffer, the BatchEmitter checks the number of buffered events. If it is equal to or greater than the `batchSize`, an attempt is made to send a batch of events as one request. Events are sent asynchronously. If the request is unsuccessful, the events are returned to the buffer. A delay is introduced for all event sending attempts. This increases exponentially until a request succeeds, when it is reset to 0. Retry will continue indefinitely. If the buffer becomes full due to network problems, newer events will be lost.

Constructor Summary

Constructors

Constructor and Description
BatchEmitter(NetworkConfiguration networkConfig) Creates a BatchEmitter instance using a NetworkConfiguration.
BatchEmitter(NetworkConfiguration networkConfig, EmitterConfiguration emitterConfig) Creates a BatchEmitter object from configuration objects.

Method Summary

Modifier and Type	Method and Description
boolean	add(TrackerPayload payload) Adds a TrackerPayload to the EventStore buffer.
void	close() Attempt to send all remaining events, then shut down the ExecutorService.
void	flushBuffer() Forces all the payloads currently in the buffer to be sent immediately, as a single request.
int	getBatchSize() Gets the Emitter batchSize
java.util.List<TrackerPayload>	getBuffer() Returns a List of Payloads that are in the buffer.
protected boolean	isSuccessfulSend(int code) Checks whether the response code was a success or not.
void	setBatchSize(int batchSize) Customize the emitter batch size to any valid integer greater than zero.
protected boolean	shouldRetry(int code)

Methods inherited from class java.lang.Object

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

Constructor Detail

BatchEmitter

public BatchEmitter(NetworkConfiguration networkConfig,
                    EmitterConfiguration emitterConfig)

Creates a BatchEmitter object from configuration objects.

Parameters:

networkConfig - a NetworkConfiguration object

emitterConfig - an EmitterConfiguration object

BatchEmitter

public BatchEmitter(NetworkConfiguration networkConfig)

Creates a BatchEmitter instance using a NetworkConfiguration.

Parameters:

networkConfig - a NetworkConfiguration object

Method Detail

add

public boolean add(TrackerPayload payload)

Adds a TrackerPayload to the EventStore buffer. If the buffer is full, the payload will be lost.

Implementation note: As a side effect it triggers an Emitter thread to emit a batch of events.

Specified by:

add in interface Emitter

Parameters:

payload - a TrackerPayload

Returns:

whether the payload has been successfully added to the buffer.

flushBuffer

public void flushBuffer()

Forces all the payloads currently in the buffer to be sent immediately, as a single request.

Specified by:

flushBuffer in interface Emitter

getBuffer

public java.util.List<TrackerPayload> getBuffer()

Returns a List of Payloads that are in the buffer.

Specified by:

getBuffer in interface Emitter

Returns:

the buffered events

setBatchSize

public void setBatchSize(int batchSize)

Customize the emitter batch size to any valid integer greater than zero.

Specified by:

setBatchSize in interface Emitter

Parameters:

batchSize - number of events to send in one request

getBatchSize

public int getBatchSize()

Gets the Emitter batchSize

Specified by:

getBatchSize in interface Emitter

Returns:

the batch size

isSuccessfulSend

protected boolean isSuccessfulSend(int code)

Checks whether the response code was a success or not.

Parameters:

code - the response code

Returns:

whether it is in the success range

shouldRetry

protected boolean shouldRetry(int code)

close

public void close()

Attempt to send all remaining events, then shut down the ExecutorService.

Implementation note: Be aware that calling `close()` has a side-effect of shutting down the Emitter ScheduledExecutorService.

Specified by:

close in interface Emitter

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable