Amazon SQS Client

Overview

Amazon Simple Queue Service (SQS) is a fully managed message queuing service that enables you to decouple and scale microservices, distributed systems, and serverless applications. SQS eliminates the complexity and overhead associated with managing and operating message oriented middleware, and empowers developers to focus on differentiating work. Using SQS, you can send, store, and receive messages between software components at any volume, without losing messages or requiring other services to be available.

At a glance

Features

• Native Delphi implementation with full ANSI/Unicode support.

Technical specification

Main properties

The principal published / public properties used to configure and drive the component. Consult the online help for the full list.

Main methods

The principal public methods exposed by the component.

Quick Start

Drop the component on a form, configure the properties below and activate it. The snippet that follows shows the typical SQS Client configuration sourced from the online help.

Delphi (VCL / FireMonkey)

// <b>TsgcHTTPAWS_SQS_Client</b> is the component used for connect to Amazon SQS. 
// Client connects using HTTPs protocol and authenticates using Access Key provided by Amazon.
 
// Before you attempt to connect to SQS service, you must set some data in <b>AWSOptions</b> property.
 
// <b>Region:</b> your endpoint region, example: us-east-1.
// <b>AccessKey:</b> access key provided by Amazon.
// <b>SecretKey:</b> secret key provided by Amazon.
 
// The following methods are supported by SQS client:
 
// <b>AddPermission</b>
// Adds a permission to a queue for a specific principal. This allows sharing access to the queue.
 
// <b>ChangeMessageVisibility</b>
// Changes the visibility timeout of a specified message in a queue to a new value. The default visibility timeout for a message is 30 seconds. 
// The minimum is 0 seconds. The maximum is 12 hours.
 
// <b>ChangeMessageVisibilityBatch</b>
 
// Changes the visibility timeout of multiple messages. This is a batch version of ChangeMessageVisibility. 
// The result of the action on each message is reported individually in the response. You can send up to 10 ChangeMessageVisibility requests.
 
// <b>CreateQueue</b>
// Creates a new standard or FIFO queue. You can pass one or more attributes in the request.
 
  vURL := SQS.CreateQueue('sqs_queue');
  if vURL  '' then
    DoLog('#CreateQueue: ' + vURL);
 
// <b>DeleteMessage</b>
// Deletes the specified message from the specified queue. To select the message to delete, use the ReceiptHandle of the message.
 
  if SQS.DeleteMessage('sqs_queue', '...receipt handle goes here...') then
    DoLog('#DeleteMessage: ok');
  else
    DoLog('#DeleteMessage: error');
 
// <b>DeleteMessageBatch</b>
// Deletes up to ten messages from the specified queue. This is a batch version of DeleteMessage. The result of the action on each message is reported individually in the response.
 
// <b>DeleteQueue</b>
// Deletes the queue specified by the queue name, regardless of the queue's contents.
 
  if SQS.DeleteQueue(txtQueueName.Text) then
    DoLog('#Delete Queue: ok')
  else
    DoLog('#Delete Queue: error');
 
// <b>GetQueueAttributes</b>
// Gets attributes for the specified queue.
 
  oAttributes := TsgcSQSAttributes.Create;
  Try
    if SQS.GetQueueAttributes('sqs_queue', oAttributes) then
    begin
      for i := 0 to oAttributes.Count - 1 do
        DoLog('#Attribute: ' + TsgcSQSAttribute(oAttributes->Item[i])
          .AttributeName + ' ' + TsgcSQSAttribute(oAttributes->Item[i])
          .AttributeValue);
    end
    else
      DoLog('#GetQueueAttributes: error');
  Finally
    FreeAndNil(oAttributes);
  End;
 
// <b>GetQueueUrl</b>
// Returns the URL of an existing Amazon SQS queue.
  
// <b>ListDeadLetterSourceQueues</b>
// Returns a list of your queues that have the RedrivePolicy queue attribute configured with a dead-letter queue.
 
// <b>ListQueueTags</b>
// List all cost allocation tags added to the specified Amazon SQS queue.
 
// <b>PurgeQueue</b>
// Deletes the messages in a queue specified by the QueueName parameter.
 
  if SQS.PurgueQueue('sqs_queue') then
    DoLog('#PurgueQueue: ok')
  else
    DoLog('#PurgueQueue: error');
 
// <b>ReceiveMessage</b>
// Retrieves one or more messages (up to 10), from the specified queue.
 
  oResponses := TsgcSQSReceiveMessageResponses.Create;
  Try
    if SQS.ReceiveMessage('sqs_test', oResponses) then
    begin
      for i := 0 to oResponses.Count - 1 do
      begin
        DoLog('#ReceiveMessage: ' + TsgcSQSReceiveMessageResponse(oResponses.Item[i]).Body);
        FReceiptHandle := TsgcSQSReceiveMessageResponse(oResponses.Item[i]).ReceiptHandle;
      end;
    end;
  Finally
    FreeAndNil(oResponses);
  End;
 
// <b>RemovePermission</b>
// Revokes any permissions in the queue policy that matches the specified Label parameter.
 
// <b>SendMessage</b>
// Delivers a message to the specified queue.
 
  if SQS.SendMessage('sqs_queue', 'My First Message') then
    DoLog('#SendMessage: ok')
  else
    DoLog('#SendMessage: error');
 
// <b>SendMessageBatch</b>
// Delivers up to ten messages to the specified queue. This is a batch version of SendMessage.
 
// <b>SetQueueAttributes</b>
// Sets the value of one or more queue attributes. When you change a queue's attributes, the change can take up to 60 seconds 
// for most of the attributes to propagate throughout the Amazon SQS system. 
 
  oAttributes := TsgcSQSAttributes.Create;
  Try
    oAttributes.AddSQSAttribute(sqsatVisibilityTimeout, '45');
    if SQS.SetQueueAttributes('sqs_queue', oAttributes) then
      DoLog('#SetQueueAttributes: ok')
    else
      DoLog('#SetQueueAttributes: error');
  Finally
    FreeAndNil(oAttributes);
  End;
 
// <b>TagQueue</b>
// Add cost allocation tags to the specified Amazon SQS queue.
 
// <b>UntagQueue</b>
// Remove cost allocation tags from the specified Amazon SQS queue.

C++ Builder

// <b>TsgcHTTPAWS_SQS_Client</b> is the component used for connect to Amazon SQS. 
// Client connects using HTTPs protocol and authenticates using Access Key provided by Amazon.
 
// Before you attempt to connect to SQS service, you must set some data in <b>AWSOptions</b> property.
 
// <b>Region:</b> your endpoint region, example: us-east-1.
// <b>AccessKey:</b> access key provided by Amazon.
// <b>SecretKey:</b> secret key provided by Amazon.
 
// The following methods are supported by SQS client:
 
// <b>AddPermission</b>
// Adds a permission to a queue for a specific principal. This allows sharing access to the queue.
 
// <b>ChangeMessageVisibility</b>
// Changes the visibility timeout of a specified message in a queue to a new value. The default visibility timeout for a message is 30 seconds. 
// The minimum is 0 seconds. The maximum is 12 hours.
 
// <b>ChangeMessageVisibilityBatch</b>
 
// Changes the visibility timeout of multiple messages. This is a batch version of ChangeMessageVisibility. 
// The result of the action on each message is reported individually in the response. You can send up to 10 ChangeMessageVisibility requests.
 
// <b>CreateQueue</b>
// Creates a new standard or FIFO queue. You can pass one or more attributes in the request.
 
  vURL = SQS->CreateQueue("sqs_queue");
  if (vURL != "")
  {
    DoLog("#CreateQueue: " + vURL);
  }
 
// <b>DeleteMessage</b>
// Deletes the specified message from the specified queue. To select the message to delete, use the ReceiptHandle of the message.
 
  if (SQS->DeleteMessage("sqs_queue", "...receipt handle goes here...") == true)
  {
    DoLog("#DeleteMessage: ok");
  }
  else
  {
    DoLog("#DeleteMessage: error");
  }
 
// <b>DeleteMessageBatch</b>
// Deletes up to ten messages from the specified queue. This is a batch version of DeleteMessage. The result of the action on each message is reported individually in the response.
 
// <b>DeleteQueue</b>
// Deletes the queue specified by the queue name, regardless of the queue's contents.
 
  if (SQS->DeleteQueue(txtQueueName->Text) == true)
  {
    DoLog("#Delete Queue: ok");
  }
  else
  {
    DoLog("#Delete Queue: error");
  }
 
// <b>GetQueueAttributes</b>
// Gets attributes for the specified queue.
 
  TsgcSQSAttributes *oAttributes = new TsgcSQSAttributes();
  try
  {
    if (SQS->GetQueueAttributes("sqs_queue", oAttributes) == true)
    {
      for (int i = 0; i < oAttributes->Count; i++)
      {
        DoLog("#Attribute: " + static_cast<TsgcSQSAttribute*>(oAttributes->Item[i])
          ->AttributeName + " " + static_cast<TsgcSQSAttribute*>(oAttributes->Item[i])
          ->AttributeValue);
      }
    }
    else
    {
      DoLog("#GetQueueAttributes: error");
    }
  }
  __finally
  {
      oAttributes->Free();
  }
 
// <b>GetQueueUrl</b>
// Returns the URL of an existing Amazon SQS queue.
  
// <b>ListDeadLetterSourceQueues</b>
// Returns a list of your queues that have the RedrivePolicy queue attribute configured with a dead-letter queue.
 
// <b>ListQueueTags</b>
// List all cost allocation tags added to the specified Amazon SQS queue.
 
// <b>PurgeQueue</b>
// Deletes the messages in a queue specified by the QueueName parameter.
 
  if (SQS->PurgueQueue("sqs_queue") == true)
  {
    DoLog("#PurgueQueue: ok");
  }
  else
  {
    DoLog("#PurgueQueue: error");
  }
 
// <b>ReceiveMessage</b>
// Retrieves one or more messages (up to 10), from the specified queue.
 
  TsgcSQSReceiveMessageResponses *oResponses = new TsgcSQSReceiveMessageResponses();
  try
  {
    if (SQS->ReceiveMessage("sqs_test", oResponses) == true)
    {
      for (int i = 0; i < oResponses->Count; i++)
      {
        DoLog("#ReceiveMessage: " + static_cast<TsgcSQSReceiveMessageResponse*>(oResponses->Item[i])->Body);
        FReceiptHandle = static_cast<TsgcSQSReceiveMessageResponse*>(oResponses->Item[i])->ReceiptHandle;
      }
    }
  }
  __finally
  {
    oResponses->Free();
  }
 
// <b>RemovePermission</b>
// Revokes any permissions in the queue policy that matches the specified Label parameter.
 
// <b>SendMessage</b>
// Delivers a message to the specified queue.
 
  if (SQS->SendMessage("sqs_queue", "My First Message") == true)
  {
    DoLog("#SendMessage: ok");
  }
  else
  {
    DoLog("#SendMessage: error");
  }
 
// <b>SendMessageBatch</b>
// Delivers up to ten messages to the specified queue. This is a batch version of SendMessage.
 
// <b>SetQueueAttributes</b>
// Sets the value of one or more queue attributes. When you change a queue's attributes, the change can take up to 60 seconds 
// for most of the attributes to propagate throughout the Amazon SQS system. 
 
  TsgcSQSAttributes *oAttributes = new TsgcSQSAttributes();
  try
  {
    oAttributes->AddSQSAttribute(sqsatVisibilityTimeout, "45");
    if (SQS->SetQueueAttributes("sqs_queue", oAttributes) == true)
    {
      DoLog("#SetQueueAttributes: ok");
    }
    else
    {
      DoLog("#SetQueueAttributes: error");
    }
  }
  __finally
  {
    oAttributes->Free();
  }
 
// <b>TagQueue</b>
// Add cost allocation tags to the specified Amazon SQS queue.
 
// <b>UntagQueue</b>
// Remove cost allocation tags from the specified Amazon SQS queue.

.NET (C#)

Sources used to build this document

Every external claim links back to a primary source. The online-help references decode the canonical deep-link the company maintains for this component.