Pascal (Lazarus/Delphi)

RSAP Union API - Get OAuth2 Access Token

See more _Miscellaneous_ Examples

Demonstrates how to get an OAuth2 access token for the RSAP Union API. Note: This uses the client credentials flow, which does NOT require an interactive engagement using a browser. 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.StringBuilder,
  Chilkat.JsonObject,
  Chilkat.PrivateKey,
  Chilkat.Cert,
  Chilkat.Http;

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

procedure RunDemo;
var
  success: Boolean;
  http: THttp;
  json: TJsonObject;
  cert: TCert;
  privKey: TPrivateKey;
  resp: THttpResponse;
  sbResponseBody: TStringBuilder;
  jResp: TJsonObject;
  respStatusCode: Integer;

begin
  success := False;

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

  http := THttp.Create;

  //  The following JSON is sent in the request body.

  //  {
  //    "grant_type": "client_credentials",
  //    "client_id": 1234,
  //    "client_secret": "23456abcde"
  //  }

  json := TJsonObject.Create;
  json.UpdateString('grant_type','client_credentials');
  json.UpdateInt('client_id',1234);
  json.UpdateString('client_secret','23456abcde');

  http.SetRequestHeader('Content-type','application/json');

  //  Add the client certificate TLS authentication.
  cert := TCert.Create;
  success := cert.LoadFromFile('qa_data/certs_and_keys/union_client_certificate.crt');
  if (success = False) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  privKey := TPrivateKey.Create;
  success := privKey.LoadAnyFormatFile('qa_data/certs_and_keys/union_client_certificate.nopass.key','');
  if (success = False) then
    begin
      WriteLn(privKey.LastErrorText);
      Exit;
    end;

  //  Associate the private key with the cert.
  //  This will fail if the private key is not actually the correct one that corresponds to the public key stored within the cert.
  success := cert.SetPrivateKey(privKey);
  if (success = False) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  //  Tell HTTP to use the cert for client TLS certificate authentication.
  success := http.SetSslClientCert(cert);
  if (success = False) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;

  resp := THttpResponse.Create;
  success := http.HttpJson('POST','https://api-test.rsap.ca/oauth/token',json,'application/json',resp);
  if (success = False) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;

  sbResponseBody := TStringBuilder.Create;
  resp.GetBodySb(sbResponseBody);
  jResp := TJsonObject.Create;
  jResp.LoadSb(sbResponseBody);
  jResp.EmitCompact := False;

  WriteLn('Response Body:');
  WriteLn(jResp.Emit());

  respStatusCode := resp.StatusCode;
  WriteLn('Response Status Code = ' + respStatusCode);
  if (respStatusCode >= 400) then
    begin
      WriteLn('Response Header:');
      WriteLn(resp.Header);
      WriteLn('Failed.');
      Exit;
    end;

  //  Sample JSON response:
  //  (Sample code for parsing the JSON response is shown below)

  //  {
  //    "token_type": "Bearer",
  //    "expires_in": 3600,
  //    "access_token": "eyJ0eXAi...LnE"
  //  }

  //  This token expires in 1 hour.  Your application could re-use the same token for up to an hour,
  //  or it can simply get a new access token before each request (if you're not doing too many requests).
  success := jResp.WriteFile('qa_data/tokens/rsapToken.json');


  http.Free;
  json.Free;
  cert.Free;
  privKey.Free;
  resp.Free;
  sbResponseBody.Free;
  jResp.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.