Pascal (Lazarus/Delphi)
SQS Delete Message

Deletes a message from an SQS queue. You specify the message by using the message's receipt handle and not the message ID you received when you sent the message. This example will first receive a message, and then use the receipt handle to delete it.
See SQS DeleteMessage or detailed information.
Chilkat Pascal (Lazarus/Delphi) Downloads

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Pascal (Lazarus/Delphi)
program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.AuthAws,
  Chilkat.Rest,
  Chilkat.Xml;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  rest: TRest;
  bTls: Boolean;
  port: Integer;
  bAutoReconnect: Boolean;
  authAws: TAuthAws;
  responseXml: string;
  xml: TXml;
  receiptHandle: string;

begin
  success := False;

  //  This example requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  rest := TRest.Create;

  //  Connect to the Amazon AWS REST server.
  //  such as https://sqs.us-west-2.amazonaws.com/
  bTls := True;
  port := 443;
  bAutoReconnect := True;
  success := rest.Connect('sqs.us-west-2.amazonaws.com',port,bTls,bAutoReconnect);

  //  Provide AWS credentials for the REST call.
  authAws := TAuthAws.Create;
  authAws.AccessKey := 'AWS_ACCESS_KEY';
  authAws.SecretKey := 'AWS_SECRET_KEY';
  //  the region should match our URL above..
  authAws.Region := 'us-west-2';
  authAws.ServiceName := 'sqs';

  rest.SetAuthAws(authAws);

  rest.AddQueryParam('Action','ReceiveMessage');
  rest.AddQueryParam('MaxNumberOfMessages','5');
  rest.AddQueryParam('VisibilityTimeout','15');
  rest.AddQueryParam('AttributeName','All');
  rest.AddQueryParam('MessageAttributeName','All');

  //  Use the actual path part of your SQS queue URL here:
  responseXml := rest.FullRequestNoBody('GET','/123456789123/chilkatTest');
  if (rest.LastMethodSuccess <> True) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  A successful response will have a status code equal to 200.
  if (rest.ResponseStatusCode <> 200) then
    begin
      WriteLn('response status code = ' + rest.ResponseStatusCode);
      WriteLn('response status text = ' + rest.ResponseStatusText);
      WriteLn('response header: ' + rest.ResponseHeader);
      WriteLn('response body: ' + responseXml);
      Exit;
    end;

  //  Examine the successful XML response.
  xml := TXml.Create;
  xml.LoadXml(responseXml);

  //  A successful response looks like this:
  //  <?xml version="1.0" encoding="utf-8" ?>
  //  <ReceiveMessageResponse xmlns="http://queue.amazonaws.com/doc/2012-11-05/">
  //      <ReceiveMessageResult>
  //          <Message>
  //              <Body>this is a test</Body>
  //              <MD5OfBody>54b0c58c7ce9f2a8b551351102ee0938</MD5OfBody>
  //              <ReceiptHandle>AQEBMyLof...UbKBTvHtEg==</ReceiptHandle>
  //              <Attribute>
  //                  <Name>SenderId</Name>
  //                  <Value>957491831129</Value>
  //              </Attribute>
  //  ...
  //  ...
  //              <MessageId>52882c65-5e21-4450-9024-93a3b01e61d3</MessageId>
  //              <MD5OfMessageAttributes>2ff68603f4239272bd03f543254ed040</MD5OfMessageAttributes>
  //          </Message>
  //      </ReceiveMessageResult>
  //      <ResponseMetadata>
  //          <RequestId>05ba5c92-80ee-5f87-be76-0cf67b7475d6</RequestId>
  //      </ResponseMetadata>
  //  </ReceiveMessageResponse>

  //  Get some values from the XML:
  receiptHandle := xml.ChilkatPath('ReceiveMessageResult|Message|ReceiptHandle|*');
  WriteLn('ReceiptHandle = ' + receiptHandle);

  //  Now use the receipt handle to delete the message.
  //  Use the same connection (or automatically reconnect if needed)
  rest.ClearAllQueryParams();

  rest.AddQueryParam('Action','DeleteMessage');
  rest.AddQueryParam('ReceiptHandle',receiptHandle);

  //  Use the actual path part of your SQS queue URL here:
  responseXml := rest.FullRequestNoBody('GET','/123456789123/chilkatTest');
  if (rest.LastMethodSuccess <> True) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  A successful response will have a status code equal to 200.
  if (rest.ResponseStatusCode <> 200) then
    begin
      WriteLn('response status code = ' + rest.ResponseStatusCode);
      WriteLn('response status text = ' + rest.ResponseStatusText);
      WriteLn('response header: ' + rest.ResponseHeader);
      WriteLn('response body: ' + responseXml);
      Exit;
    end;

  //  Examine the successful XML response.
  xml.LoadXml(responseXml);
  WriteLn(xml.GetXml());

  //  A successful DeleteMessage response looks like this:
  //  <DeleteMessageResponse>
  //      <ResponseMetadata>
  //          <RequestId>
  //              b5293cb5-d306-4a17-9048-b263635abe42
  //          </RequestId>
  //      </ResponseMetadata>
  //  </DeleteMessageResponse>


  rest.Free;
  authAws.Free;
  xml.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.