Pascal (Lazarus/Delphi)

Bunny Sign URL and then Download using Signed URL

See more Bunny CDN Examples

Shows how to sign a URL for BunnyCDN Token Authentication and then use it to download. 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.Http,
  Chilkat.StringBuilder,
  Chilkat.Url,
  Chilkat.CkDateTime;

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

procedure RunDemo;
var
  success: Boolean;
  mySecurityKey: string;
  url: string;
  urlObj: TUrl;
  url_scheme: string;
  url_host: string;
  url_path: string;
  expTime: TCkDateTime;
  expires: string;
  sbToHash: TStringBuilder;
  token: string;
  sbSignedUrl: TStringBuilder;
  signedUrl: string;
  http: THttp;

begin
  success := False;

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

  mySecurityKey := 'e7ea8d73-8fa0-44ef-a2cc-91526f7df5ed';

  url := 'https://test.b-cdn.net/sample-pdf-with-images.pdf';

  //  Extract the URL components.
  urlObj := TUrl.Create;
  urlObj.ParseUrl(url);

  url_scheme := 'https';
  if (urlObj.Ssl = False) then
    begin
      url_scheme := 'http';
    end;

  url_host := urlObj.Host;
  url_path := urlObj.Path;

  //  Calculate an expiration time 1 hour from the current date/time.
  expTime := TCkDateTime.Create;
  expTime.SetFromCurrentSystemTime();
  expTime.AddSeconds(3600);
  expires := expTime.GetAsUnixTimeStr(False);

  WriteLn('Expires = ' + expires);

  //  Create the string to hash
  sbToHash := TStringBuilder.Create;
  sbToHash.Append(mySecurityKey);
  sbToHash.Append(url_path);
  sbToHash.Append(expires);

  //  Base64Url encoding is the same as base64, except "-" is used instead of "+",
  //  "_" is used instead of "/", and no "=" padding is added.
  token := sbToHash.GetHash('sha256','base64Url','utf-8');

  sbSignedUrl := TStringBuilder.Create;
  sbSignedUrl.Append(url_scheme);
  sbSignedUrl.Append('://');
  sbSignedUrl.Append(url_host);
  sbSignedUrl.Append(url_path);
  sbSignedUrl.Append('?token=');
  sbSignedUrl.Append(token);
  sbSignedUrl.Append('&expires=');
  sbSignedUrl.Append(expires);

  signedUrl := sbSignedUrl.GetAsString();
  WriteLn('Signed URL: ' + signedUrl);

  //  Use the signed URL to download the file.
  http := THttp.Create;
  success := http.Download(signedUrl,'c:/aaworkarea/sample.pdf');
  if (success = False) then
    begin
      WriteLn(http.LastErrorText);
    end
  else
    begin
      WriteLn('Success.');
    end;


  urlObj.Free;
  expTime.Free;
  sbToHash.Free;
  sbSignedUrl.Free;
  http.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.