Package com.amazonaws.athena.connector.lambda.handlers

Class CompositeHandler

java.lang.Object

com.amazonaws.athena.connector.lambda.handlers.CompositeHandler

All Implemented Interfaces:

com.amazonaws.services.lambda.runtime.RequestStreamHandler

Direct Known Subclasses:

AmazonMskCompositeHandler, AwsCmdbCompositeHandler, BigQueryCompositeHandler, ClickHouseCompositeHandler, CloudwatchCompositeHandler, DataLakeGen2CompositeHandler, Db2As400CompositeHandler, Db2CompositeHandler, DocDBCompositeHandler, DynamoDBCompositeHandler, ElasticsearchCompositeHandler, ExampleCompositeHandler, GcsCompositeHandler, HbaseCompositeHandler, HiveCompositeHandler, HiveCompositeHandler, ImpalaCompositeHandler, KafkaCompositeHandler, MetricsCompositeHandler, MultiplexingJdbcCompositeHandler, MySqlCompositeHandler, NeptuneCompositeHandler, OracleCompositeHandler, PostGreSqlCompositeHandler, RedisCompositeHandler, SaphanaCompositeHandler, SnowflakeCompositeHandler, SqlServerCompositeHandler, SynapseCompositeHandler, TeradataCompositeHandler, TimestreamCompositeHandler, TPCDSCompositeHandler, VerticaCompositeHandler

public class CompositeHandler
extends Object
implements com.amazonaws.services.lambda.runtime.RequestStreamHandler

This class allows you to have a single Lambda function be responsible for both metadata and data operations by composing a MetadataHandler with a RecordHandler and muxing requests to the appropriate class. You might choose to use this CompositeHandler to run a single lambda function for the following reasons: 1. Can be simpler to deploy and manage a single vs multiple Lambda functions 2. You don't need to independently control the cost or performance of metadata vs. data operations.

See Also:

RequestStreamHandler

Constructor Summary

Constructors

Constructor	Description
CompositeHandler(MetadataHandler metadataHandler, RecordHandler recordHandler)	Basic constructor that composes a MetadataHandler with a RecordHandler.
CompositeHandler(MetadataHandler metadataHandler, RecordHandler recordHandler, UserDefinedFunctionHandler udfhandler)	Basic constructor that composes a MetadataHandler, RecordHandler, and a UserDefinedFunctionHandler

Method Summary

Modifier and Type	Method	Description
void	handleRequest(BlockAllocator allocator, FederationRequest rawReq, OutputStream outputStream, com.fasterxml.jackson.databind.ObjectMapper objectMapper)	Handles routing the request to the appropriate Handler, either MetadataHandler or RecordHandler.
void	handleRequest(InputStream inputStream, OutputStream outputStream, com.amazonaws.services.lambda.runtime.Context context)	Required by Lambda's RequestStreamHandler interface.

Methods inherited from class java.lang.Object

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

Constructor Detail

CompositeHandler

public CompositeHandler(MetadataHandler metadataHandler,
                        RecordHandler recordHandler)

Basic constructor that composes a MetadataHandler with a RecordHandler.

Parameters:

metadataHandler - The MetadataHandler to delegate metadata operations to.

recordHandler - The RecordHandler to delegate data operations to.

CompositeHandler

public CompositeHandler(MetadataHandler metadataHandler,
                        RecordHandler recordHandler,
                        UserDefinedFunctionHandler udfhandler)

Basic constructor that composes a MetadataHandler, RecordHandler, and a UserDefinedFunctionHandler

Parameters:

metadataHandler - The MetadataHandler to delegate metadata operations to.

recordHandler - The RecordHandler to delegate data operations to.

udfhandler - The UserDefinedFunctionHandler to delegate UDF operations to.

Method Detail

handleRequest

public final void handleRequest(InputStream inputStream,
                                OutputStream outputStream,
                                com.amazonaws.services.lambda.runtime.Context context)
                         throws IOException

Required by Lambda's RequestStreamHandler interface. In our case we use this method to handle some basic resource lifecycle tasks for the request, namely the BlockAllocator and the request object itself.

Specified by:

handleRequest in interface com.amazonaws.services.lambda.runtime.RequestStreamHandler

Throws:

IOException

handleRequest

public final void handleRequest(BlockAllocator allocator,
                                FederationRequest rawReq,
                                OutputStream outputStream,
                                com.fasterxml.jackson.databind.ObjectMapper objectMapper)
                         throws Exception

Handles routing the request to the appropriate Handler, either MetadataHandler or RecordHandler.

Parameters:

allocator - The BlockAllocator to use for Apache Arrow Resources.

rawReq - The request object itself.

outputStream - The OutputStream to which all responses should be written.

objectMapper - The ObjectMapper that can be used for serializing responses.

Throws:

Exception