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2 changes: 1 addition & 1 deletion .github/workflows/workflow.yml
Original file line number Diff line number Diff line change
Expand Up @@ -31,7 +31,7 @@ jobs:
with:
aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
aws-region: us-east-1 #AWS region where you want to use CodeGuru
aws-region: eu-west-1 #AWS region where you want to use CodeGuru

- name: CodeGuru Reviewer
uses: aws-actions/codeguru-reviewer@v1.1
Expand Down
48 changes: 48 additions & 0 deletions pom.xml
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@@ -0,0 +1,48 @@
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>sample-applications</groupId>
<artifactId>Guru-Sample-application</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>Guru-Sample-application</name>
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-lambda-java-core</artifactId>
<version>1.2.0</version>
</dependency>
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-lambda-java-events</artifactId>
<version>2.2.6</version>
</dependency>
<dependency>
<groupId>com.amazonaws</groupId>
<artifactId>aws-java-sdk-s3</artifactId>
<version>1.11.624</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.8</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.2.1</version>
</plugin>
</plugins>
</build>
</project>
174 changes: 174 additions & 0 deletions src/main/java/EventHandler.java
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@@ -0,0 +1,174 @@
package com.shipmentEvents.handlers;

import java.time.Duration;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import com.amazonaws.regions.Regions;
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.LambdaLogger;
import com.amazonaws.services.lambda.runtime.events.ScheduledEvent;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.DeleteObjectsRequest;
import com.amazonaws.services.s3.model.DeleteObjectsRequest.KeyVersion;
import com.amazonaws.services.s3.model.ObjectListing;
import com.amazonaws.services.s3.model.S3ObjectSummary;
import com.shipmentEvents.util.Constants;

import org.apache.commons.lang3.tuple.MutablePair;
import org.apache.commons.lang3.tuple.Pair;


public class EventHandler implements RequestHandler<ScheduledEvent, String> {

/**
* Shipment events for a carrier are uploaded to separate S3 buckets based on the source of events. E.g., events originating from
* the hand-held scanner are stored in a separate bucket than the ones from mobile App. The Lambda processes events from multiple
* sources and updates the latest status of the package in a summary S3 bucket every 15 minutes.
*
* The events are stored in following format:
* - Each status update is a file, where the name of the file is tracking number + random id.
* - Each file has status and time-stamp as the first 2 lines respectively.
* - The time at which the file is stored in S3 is not an indication of the time-stamp of the event.
* - Once the status is marked as DELIVERED, we can stop tracking the package.
*
* A Sample files looks as below:
* FILE-NAME-> '8787323232232332--55322798-dd29-4a04-97f4-93e18feed554'
* >status:IN TRANSIT
* >timestamp: 1573410202
* >Other fields like...tracking history and address
*/
public String handleRequest(ScheduledEvent scheduledEvent, Context context) {

final LambdaLogger logger = context.getLogger();
try {
processShipmentUpdates(logger);
return "SUCCESS";
} catch (final Exception ex) {
logger.log(String.format("Failed to process shipment Updates in %s due to %s", scheduledEvent.getAccount(), ex.getMessage()));
throw new RuntimeException(ex);
}
}


private void processShipmentUpdates(final LambdaLogger logger) throws InterruptedException {

final List<String> bucketsToProcess = Constants.BUCKETS_TO_PROCESS;
final Map<String, Pair<Long, String>> latestStatusForTrackingNumber = new HashMap<String, Pair<Long, String>>();
final Map<String, List<KeyVersion>> filesToDelete = new HashMap<String, List<DeleteObjectsRequest.KeyVersion>>();
for (final String bucketName : bucketsToProcess) {
final List<KeyVersion> filesProcessed = processEventsInBucket(bucketName, logger, latestStatusForTrackingNumber);
filesToDelete.put(bucketName, filesProcessed);
}
final AmazonS3 s3Client = EventHandler.getS3Client();

//Create a new file in the Constants.SUMMARY_BUCKET
logger.log("Map of statuses -> " + latestStatusForTrackingNumber);
String summaryUpdateName = Long.toString(System.currentTimeMillis());

EventHandler.getS3Client().putObject(Constants.SUMMARY_BUCKET, summaryUpdateName, latestStatusForTrackingNumber.toString());

long expirationTime = System.currentTimeMillis() + Duration.ofMinutes(1).toMillis();
while(System.currentTimeMillis() < expirationTime) {
if (s3Client.doesObjectExist(Constants.SUMMARY_BUCKET, summaryUpdateName)) {

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Recommendation generated by Amazon CodeGuru Reviewer. Leave feedback on this recommendation by replying to the comment or by reacting to the comment using emoji.

This code appears to be waiting for a resource before it runs. You could use the waiters feature to help improve efficiency. Consider using ObjectExists or ObjectNotExists. For more information, see https://aws.amazon.com/blogs/developer/waiters-in-the-aws-sdk-for-java/

break;
}
logger.log("waiting for file to be created " + summaryUpdateName);
Thread.sleep(1000);
}

// Before we delete the shipment updates make sure the summary update file exists
if (EventHandler.getS3Client().doesObjectExist(Constants.SUMMARY_BUCKET, summaryUpdateName)) {
deleteProcessedFiles(filesToDelete);
logger.log("All updates successfully processed");
} else {
throw new RuntimeException("Failed to write summary status, will be retried in 15 minutes");
}

}

private List<KeyVersion> processEventsInBucket(String bucketName, LambdaLogger logger, Map<String, Pair<Long, String>> latestStatusForTrackingNumber) {
final AmazonS3 s3Client = EventHandler.getS3Client();
logger.log("Processing Bucket: " + bucketName);

ObjectListing files = s3Client.listObjects(bucketName);

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Recommendation generated by Amazon CodeGuru Reviewer. Leave feedback on this recommendation by replying to the comment or by reacting to the comment using emoji.

This code uses an outdated API. ListObjectsV2 is the revised List Objects API, and we recommend you use this revised API for new application developments.

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Recommendation generated by Amazon CodeGuru Reviewer. Leave feedback on this recommendation by replying to the comment or by reacting to the comment using emoji.

This code might not produce accurate results if the operation returns paginated results instead of all results. Consider adding another call to check for additional results.

List<KeyVersion> filesProcessed = new ArrayList<DeleteObjectsRequest.KeyVersion>();

for (Iterator<?> iterator = files.getObjectSummaries().iterator(); iterator.hasNext(); ) {
S3ObjectSummary summary = (S3ObjectSummary) iterator.next();
logger.log("Reading Object: " + summary.getKey());

String trackingNumber = summary.getKey().split("--")[0];
Pair<Long, String> lastKnownStatus = latestStatusForTrackingNumber.get(trackingNumber);

// Check if this shipment has already been delivered, skip this file
if (lastKnownStatus != null && "DELIVERED".equals(lastKnownStatus.getRight())) {
continue;
}

String fileContents = s3Client.getObjectAsString(bucketName, summary.getKey());

if (!isValidFile(fileContents)) {
logger.log(String.format("Skipping invalid file %s", summary.getKey()));
continue;
}

if (!fileContents.contains("\n")) {

}
String[] lines = fileContents.split("\n");
String line1 = lines[0];
String line2 = lines[1];

String status = line1.split(":")[1];
Long timeStamp = Long.parseLong(line2.split(":")[1]);


if (null == lastKnownStatus || lastKnownStatus.getLeft() < timeStamp) {
lastKnownStatus = new MutablePair<Long, String>(timeStamp, status);
latestStatusForTrackingNumber.put(trackingNumber, lastKnownStatus);
}

//Add to list of processed files
filesProcessed.add(new KeyVersion(summary.getKey()));
logger.log("logging file contents" + fileContents);
}
return filesProcessed;
}


private void deleteProcessedFiles(Map<String, List<KeyVersion>> filesToDelete) {
final AmazonS3 s3Client = EventHandler.getS3Client();
for (Entry<String, List<KeyVersion>> entry : filesToDelete.entrySet()) {
final DeleteObjectsRequest deleteRequest = new DeleteObjectsRequest(entry.getKey()).withKeys(entry.getValue()).withQuiet(false);
s3Client.deleteObjects(deleteRequest);
}
}

private boolean isValidFile(String fileContents) {
if (!fileContents.contains("\n")) {
return false;
}
String[] lines = fileContents.split("\n");
for (String l: lines) {
if (!l.contains(":")) {
return false;
}
}
return true;
}

public static AmazonS3 getS3Client() {
return AmazonS3ClientBuilder.standard().withRegion(Regions.DEFAULT_REGION).build();

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Recommendation generated by Amazon CodeGuru Reviewer. Leave feedback on this recommendation by replying to the comment or by reacting to the comment using emoji.

This code is written so that the client cannot be reused across invocations of the Lambda function.
To improve the performance of the Lambda function, consider using static initialization/constructor, global/static variables and singletons. It allows to keep alive and reuse HTTP connections that were established during a previous invocation.
Learn more about best practices for working with AWS Lambda functions.

}


}


10 changes: 10 additions & 0 deletions src/main/java/com/shipmentEvents/util/Constants.java
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package com.shipmentEvents.util;

import java.util.Arrays;
import java.util.List;

public final class Constants {

public static final List<String> BUCKETS_TO_PROCESS = Arrays.asList("shipment-events-from-scanner", "shipment-events-from-mobile-app");
public static final String SUMMARY_BUCKET = "shipment-events-summary";
}
13 changes: 13 additions & 0 deletions src/main/java/com/shipmentEvents/util/S3ClientUtil.java
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package com.shipmentEvents.util;

import com.amazonaws.regions.Regions;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;

public class S3ClientUtil {

public static AmazonS3 getS3Client() {
return AmazonS3ClientBuilder.standard().withRegion(Regions.DEFAULT_REGION).build();
}

}