org.apache.spark.api.plugin

Interface PluginContext

@DeveloperApi
public interface PluginContext

:: DeveloperApi :: Context information and operations for plugins loaded by Spark.

An instance of this class is provided to plugins in their initialization method. It is safe for plugins to keep a reference to the instance for later use (for example, to send messages to the plugin's driver component).

Context instances are plugin-specific, so metrics and messages are tied each plugin. It is not possible for a plugin to directly interact with other plugins.

Since:

3.0.0

Method Summary

Modifier and Type	Method and Description
Object	ask(Object message) Send an RPC to the plugin's driver-side component.
SparkConf	conf() Configuration of the Spark application.
String	executorID() Executor ID of the process.
String	hostname() The host name which is being used by the Spark process for communication.
com.codahale.metrics.MetricRegistry	metricRegistry() Registry where to register metrics published by the plugin associated with this context.
java.util.Map<String,ResourceInformation>	resources() The custom resources (GPUs, FPGAs, etc) allocated to driver or executor.
void	send(Object message) Send a message to the plugin's driver-side component.

Method Detail

metricRegistry

com.codahale.metrics.MetricRegistry metricRegistry()

Registry where to register metrics published by the plugin associated with this context.

conf

SparkConf conf()

Configuration of the Spark application.

executorID

String executorID()

Executor ID of the process. On the driver, this will identify the driver.

hostname

String hostname()

The host name which is being used by the Spark process for communication.

resources

java.util.Map<String,ResourceInformation> resources()

The custom resources (GPUs, FPGAs, etc) allocated to driver or executor.

send

void send(Object message)
   throws java.io.IOException

Send a message to the plugin's driver-side component.

This method sends a message to the driver-side component of the plugin, without expecting a reply. It returns as soon as the message is enqueued for sending.

The message must be serializable.

Parameters:

message - Message to be sent.

Throws:

java.io.IOException

ask

Object ask(Object message)
    throws Exception

Send an RPC to the plugin's driver-side component.

This method sends a message to the driver-side component of the plugin, and blocks until a reply arrives, or the configured RPC ask timeout (spark.rpc.askTimeout) elapses.

If the driver replies with an error, an exception with the corresponding error will be thrown.

The message must be serializable.

Parameters:

message - Message to be sent.

Returns:

The reply from the driver-side component.

Throws:

Exception