Clean up s3-java code example

- Remove unnecessary imports and lines
- Remove gson dependency; example still works as before

Author: yualexan

sample-apps/s3-java/README.md

@@ -79,9 +79,7 @@ To invoke the function directly, run `5-invoke.sh`.
         "ExecutedVersion": "$LATEST"
     }
 
-Let the script invoke the function a few times and then press `CRTL+C` to exit. Note that you
-may see function timeouts in the first few iterations due to cold starts; after a while, they
-should begin to succeed.
+Let the script invoke the function a few times and then press `CRTL+C` to exit.
 
 If you look at the `s3-java-bucket-<random_uuid>` bucket in your account, you should now see a
 key `resized-inbound/sample-s3-java.png` file, which represents the new, shrunken image.

sample-apps/s3-java/build.gradle

@@ -19,7 +19,6 @@ dependencies {
     implementation 'com.amazonaws:aws-xray-recorder-sdk-core'
     implementation 'com.amazonaws:aws-xray-recorder-sdk-aws-sdk'
     implementation 'com.amazonaws:aws-xray-recorder-sdk-aws-sdk-instrumentor'
-    implementation 'com.google.code.gson:gson:2.8.6'
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.6.0'
     testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.6.0'
 }

sample-apps/s3-java/pom.xml

@@ -78,11 +78,6 @@
       <groupId>com.amazonaws</groupId>
       <artifactId>aws-xray-recorder-sdk-aws-sdk-instrumentor</artifactId>
     </dependency>
-    <dependency>
-      <groupId>com.google.code.gson</groupId>
-      <artifactId>gson</artifactId>
-      <version>2.8.6</version>
-    </dependency>
     <dependency>
       <groupId>org.junit.jupiter</groupId>
       <artifactId>junit-jupiter-api</artifactId>

sample-apps/s3-java/src/main/java/example/Handler.java

@@ -4,7 +4,6 @@
 import java.awt.Graphics2D;
 import java.awt.RenderingHints;
 import java.awt.image.BufferedImage;
-import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -19,23 +18,18 @@
 import software.amazon.awssdk.core.sync.RequestBody;
 import software.amazon.awssdk.services.s3.model.GetObjectRequest;
 import software.amazon.awssdk.services.s3.model.PutObjectRequest;
-import software.amazon.awssdk.services.s3.model.S3Object;
 import software.amazon.awssdk.services.s3.S3Client;
 
 import com.amazonaws.services.lambda.runtime.Context;
 import com.amazonaws.services.lambda.runtime.RequestHandler;
 import com.amazonaws.services.lambda.runtime.events.S3Event;
 import com.amazonaws.services.lambda.runtime.events.models.s3.S3EventNotification.S3EventNotificationRecord;
 
-import com.google.gson.Gson;
-import com.google.gson.GsonBuilder;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 // Handler value: example.Handler
 public class Handler implements RequestHandler<S3Event, String> {
-  Gson gson = new GsonBuilder().setPrettyPrinting().create();
   private static final Logger logger = LoggerFactory.getLogger(Handler.class);
   private static final float MAX_DIMENSION = 100;
   private final String REGEX = ".*\\.([^\\.]*)";
@@ -46,7 +40,6 @@ public class Handler implements RequestHandler<S3Event, String> {
   @Override
   public String handleRequest(S3Event s3event, Context context) {
     try {
-      logger.info("EVENT: " + gson.toJson(s3event));
       S3EventNotificationRecord record = s3event.getRecords().get(0);
 
       String srcBucket = record.getS3().getBucket().getName();

sample-apps/s3-java/src/test/java/example/InvokeTest.java

@@ -1,14 +1,10 @@
 package example;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import org.junit.jupiter.api.Test;
 
 import com.amazonaws.services.lambda.runtime.Context;
-import com.amazonaws.services.lambda.runtime.LambdaLogger;
-import com.amazonaws.services.lambda.runtime.RequestHandler;
 import com.amazonaws.services.lambda.runtime.events.S3Event;
-import com.amazonaws.services.lambda.runtime.events.models.s3.S3EventNotification;
 import com.amazonaws.services.lambda.runtime.events.models.s3.S3EventNotification.RequestParametersEntity;
 import com.amazonaws.services.lambda.runtime.events.models.s3.S3EventNotification.ResponseElementsEntity;
 import com.amazonaws.services.lambda.runtime.events.models.s3.S3EventNotification.S3BucketEntity;
@@ -17,10 +13,6 @@
 import com.amazonaws.services.lambda.runtime.events.models.s3.S3EventNotification.S3ObjectEntity;
 import com.amazonaws.services.lambda.runtime.events.models.s3.S3EventNotification.UserIdentityEntity;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.util.List;
 import java.util.ArrayList;
 import java.lang.Long;
 import java.nio.file.Files;
@@ -32,7 +24,6 @@
 import com.amazonaws.xray.strategy.sampling.NoSamplingStrategy;
 
 class InvokeTest {
-  private static final Logger logger = LoggerFactory.getLogger(InvokeTest.class);
 
   public InvokeTest() {
     AWSXRayRecorderBuilder builder = AWSXRayRecorderBuilder.standard();
@@ -67,7 +58,6 @@ void invokeTest() throws IOException {
     S3Event event = new S3Event(records);
 
     Context context = new TestContext();
-    String requestId = context.getAwsRequestId();
     Handler handler = new Handler();
     String result = handler.handleRequest(event, context);
     assertTrue(result.contains("Ok"));