Pascal (Lazarus/Delphi)

Create S3 Pre-Signed URL for Upload

See more Amazon S3 Examples

Demonstrates how to generate a pre-signed URL for S3 uploads. 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.HttpResponse,
  Chilkat.Http;

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

procedure RunDemo;
var
  success: Boolean;
  http: THttp;
  bucketName: string;
  objectName: string;
  awsService: string;
  httpVerb: string;
  numSecondsValid: Integer;
  bUseHttps: Boolean;
  preSignedUrl: string;
  resp: THttpResponse;

begin
  success := False;

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

  http := THttp.Create;

  http.AwsAccessKey := 'AWS_ACCESS_KEY';
  http.AwsSecretKey := 'AWS_SECRET_KEY';

  //  Make sure to set your AWS region correctly
  http.AwsRegion := 'us-east-1';

  bucketName := 'chilkat200';
  objectName := 'starfish/starfish.jpg';
  awsService := 's3';
  httpVerb := 'PUT';

  //  The signed URL will be valid for this number of seconds:
  numSecondsValid := 86400;

  //  Choose between a URL beginning with "http://" or "https://"...
  bUseHttps := True;

  //  Generate the pre-signed URL
  preSignedUrl := http.S3_GenPresignedUrl(httpVerb,bUseHttps,bucketName,objectName,numSecondsValid,awsService);
  if (http.LastMethodSuccess = False) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;

  WriteLn('Presigned URL for Upload: ' + preSignedUrl);

  //  Here's an example of a pre-signed URL
  //  
  //  http://chilkat200.s3.amazonaws.com/starfish/starfish.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIBJLOVZVXAU2AFUA%2F20200623%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20200623T234049Z&X-Amz-Expires=86400&X-Amz-SignedHeaders=host&X-Amz-Signature=xxxxxeaea071178d772856c0a4e4c0114a8d9992f0d0812955e490d0exxxxxxx
  //  

  //  You can use the pre-signed URL to upload from Chilkat
  //  For example, upload by streaming from a local file
  resp := THttpResponse.Create;
  success := http.HttpFile('PUT',preSignedUrl,'qa_data/jpg/starfish.jpg','image/jpg',resp);
  if (success = False) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;

  WriteLn('response status code = ' + resp.StatusCode);
  WriteLn('response body size: ' + resp.ContentLength);
  if (resp.ContentLength > 0) then
    begin
      WriteLn('response body:');
      WriteLn(resp.BodyStr);
    end;


  http.Free;
  resp.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.