Tag: lambda

AWS: Java Kinesis Lambda Handler

This entry is part 2 of 5 in the series AWS & Java

If you want to write a Lambda for AWS in Java that connects to a Kinesis Stream. You need to have the handler.

Maven:

  1. <dependency>
  2.     <groupId>com.amazonaws</groupId>
  3.     <artifactId>aws-java-sdk</artifactId>
  4.     <version>1.11.109</version>
  5. </dependency>
  6. <dependency>
  7.     <groupId>com.fasterxml.jackson.core</groupId>
  8.     <artifactId>jackson-databind</artifactId>
  9.     <version>2.7.1</version>
  10. </dependency>

This is the method that AWS Lambda will call. It will look similar to the one below.

  1. import com.amazonaws.services.lambda.runtime.Context;
  2. import com.amazonaws.services.lambda.runtime.events.KinesisEvent;
  3. import com.amazonaws.services.lambda.runtime.events.KinesisEvent.KinesisEventRecord;
  4. import com.amazonaws.services.kinesis.model.Record;
  5. import com.fasterxml.jackson.databind.ObjectMapper;
  6. import com.fasterxml.jackson.databind.JsonNode;
  7.  
  8. public void kinesisRecordHandler(KinesisEvent kinesisEvent, Context context) {
  9. 	final String awsRequestId = context.getAwsRequestId();
  10. 	final int memoryLimitMb = context.getMemoryLimitInMB();
  11. 	final int remainingTimeInMillis = context.getRemainingTimeInMillis();
  12.  
  13. 	for (final KinesisEventRecord kinesisRec : kinesisEvent.getRecords()) {
  14. 		final Record record = kinesisRec.getKinesis();
  15.  
  16. 		//We get the kinesis data information
  17. 		final JsonNode recData = new ObjectMapper().readValue(record.getData().array(), JsonNode.class);
  18.  
  19. 		final String bucketName = recData.get("bucket").asText();
  20. 		final String key = recData.get("key").asText();
  21. 	}
  22. }

The thing to note when you setup you Lambda is how to setup the “Handler” field in the “Configuration” section on AWS. It is in the format “##PACKAGE##.##CLASS##::##METHOD##”.

AWS: Java S3 Lambda Handler

This entry is part 1 of 5 in the series AWS & Java

If you want to write a Lambda for AWS in Java that connects to S3. You need to have the handler.

Maven:

  1. <dependency>
  2.     <groupId>com.amazonaws</groupId>
  3.     <artifactId>aws-java-sdk</artifactId>
  4.     <version>1.11.109</version>
  5. </dependency>

This is the method that AWS Lambda will call. It will look similar to the one below.

  1. import com.amazonaws.services.lambda.runtime.Context;
  2. import com.amazonaws.services.lambda.runtime.events.S3Event;
  3. import com.amazonaws.services.s3.event.S3EventNotification.S3Entity;
  4. import com.amazonaws.services.s3.event.S3EventNotification.S3EventNotificationRecord;
  5.  
  6. public void S3Handler(S3Event s3e, Context context) {
  7. 	final String awsRequestId =  context.getAwsRequestId();
  8. 	final int memoryLimitMb = context.getMemoryLimitInMB();
  9. 	final int remainingTimeInMillis = context.getRemainingTimeInMillis();
  10.  
  11. 	for (final S3EventNotificationRecord s3Rec : s3e.getRecords()) {
  12. 		final S3Entity record = s3Rec.getS3();
  13. 		
  14. 		final String bucketName = record.getBucket().getName()
  15. 		final String key = record.getObject().getKey();
  16. 	}
  17. }

The thing to note when you setup you Lambda is how to setup the “Handler” field in the “Configuration” section on AWS. It is in the format “##PACKAGE##.##CLASS##::##METHOD##”.