sqsAlertPersist.java Source code

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Here is the source code for sqsAlertPersist.java

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/*
 * Copyright 2010-2015 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import com.amazonaws.AmazonClientException;
import com.amazonaws.AmazonServiceException;
import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.regions.Region;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
import com.amazonaws.services.dynamodbv2.model.AttributeValue;
import com.amazonaws.services.dynamodbv2.model.PutItemRequest;
import com.amazonaws.services.dynamodbv2.model.PutItemResult;
import com.amazonaws.services.sqs.AmazonSQS;
import com.amazonaws.services.sqs.model.DeleteMessageRequest;
import com.amazonaws.services.sqs.model.Message;
import com.amazonaws.services.sqs.model.SendMessageRequest;

/**
 * This sample demonstrates how to make basic requests to Amazon SQS using the
 * AWS SDK for Java.
 * <p>
 * <b>Prerequisites:</b> You must have a valid Amazon Web
 * Services developer account, and be signed up to use Amazon SQS. For more
 * information on Amazon SQS, see http://aws.amazon.com/sqs.
 * <p>
 * Fill in your AWS access credentials in the provided credentials file
 * template, and be sure to move the file to the default location
 * (/Users/johnreilly/.aws/credentials) where the sample code will load the credentials from.
 * <p>
 * <b>WARNING:</b> To avoid accidental leakage of your credentials, DO NOT keep
 * the credentials file in your source directory.
 */
public class sqsAlertPersist {

    static AmazonDynamoDBClient dynamoDB;

    public static void main(String[] args) throws Exception {

        // get credentials
        String user = "jreilly";
        AWSCredentials credentials = whgHelper.getCred(user);

        // use credentials to set access to SQS
        AmazonSQS sqs = whgHelper.setQueueAccess(credentials);

        // define queue that messages will be retrieved from
        String thisQueue = "alertPersist";
        String nextQueue = "alertCache";

        // set access to database with credentials
        dynamoDB = new AmazonDynamoDBClient(credentials);
        Region usEast1 = Region.getRegion(Regions.US_EAST_1);
        dynamoDB.setRegion(usEast1);

        // check for table, create one if missing
        String tableName = "alerts";
        whgHelper.setTable(dynamoDB, tableName);

        while (1 > 0) {

            // pull list of current messages (up to 10) in the queue
            List<Message> messages = whgHelper.getMessagesFromQueue(thisQueue, sqs);
            System.out.println("Count of messages in " + thisQueue + ": " + messages.size());

            try {

                for (Message message : messages) {

                    whgHelper.printMessage(message);
                    for (Entry<String, String> entry : message.getAttributes().entrySet()) {
                        whgHelper.printMessageEntry(entry);
                    }

                    // Add an item to DynamoDB table
                    Map<String, AttributeValue> item = whgHelper.newAlert(message.getBody());
                    PutItemRequest putItemRequest = new PutItemRequest(tableName, item);
                    PutItemResult putItemResult = dynamoDB.putItem(putItemRequest);
                    System.out.println();
                    System.out.println("Result: " + putItemResult);

                    // then send message to cache queue
                    System.out.println("Sending messages to next queue.");
                    sqs.sendMessage(new SendMessageRequest(nextQueue, message.getBody()));

                    // delete message after sending to persist queue
                    System.out.println("Deleting message from this queue.\n");
                    String messageRecieptHandle = message.getReceiptHandle();
                    sqs.deleteMessage(new DeleteMessageRequest(thisQueue, messageRecieptHandle));

                }
                Thread.sleep(20000); // do nothing for 2000 miliseconds (2 second)

            } catch (AmazonServiceException ase) {
                whgHelper.errorMessagesAse(ase);
            } catch (AmazonClientException ace) {
                whgHelper.errorMessagesAce(ace);
            }
        }
    }
}