Pascal (Lazarus/Delphi)

Auth0 Server-to-Server Access Token (Client Credentials flow)

See more HTTP Examples

Demonstrates how to obtain an Auth0 access token using client credentials (client_id and client_secret).

This is just a matter of duplicating this CURL command:

curl --request POST
  --url 'https://chilkat.auth0.com/oauth/token' \
  --header 'content-type: application/json' \
  --data '{"grant_type":"client_credentials","client_id": "xxxx","client_secret": "xxxx","audience": "https://api.example.com/geocoding/v1/"}'

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.HttpResponse,
  Chilkat.JsonObject;

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

procedure RunDemo;
var
  success: Boolean;
  json: TJsonObject;
  http: THttp;
  resp: THttpResponse;
  jsonResp: TJsonObject;

begin
  success := False;

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

  //  We want to duplicate this curl command:
  //  
  //  curl --request POST
  //    --url 'https://chilkat.auth0.com/oauth/token' \
  //    --header 'content-type: application/json' \
  //    --data '{"grant_type":"client_credentials","client_id": "my_client_id","client_secret": "my_client_secret","audience": "https://api.example.com/geocoding/v1/"}'

  //  Build the JSON body of the request.
  json := TJsonObject.Create;
  json.UpdateString('grant_type','client_credentials');
  json.UpdateString('client_id','AUTH0-CLIENT-ID');
  json.UpdateString('client_secret','AUTH0-CLIENT-SECRET');
  json.UpdateString('audience','https://api.example.com/geocoding/v1/');

  //  IMPORTANT: You would use your own url.  You would not use "chilkat.auth0.com".  
  //  Instead you would use "your_name.auth0.com"
  http := THttp.Create;
  resp := THttpResponse.Create;
  success := http.HttpJson('POST','https://chilkat.auth0.com/oauth/token',json,'application/json',resp);
  if (success = False) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;

  //  A 200 response status code indicates success.  In the success case, the response body
  //  contains the JSON access token, such as: 
  //  {
  //    "access_token": "eyJz93a...k4laUWw",
  //    "token_type":"Bearer",
  //    "expires_in":86400
  //  }
  //  

  WriteLn('response status code = ' + resp.StatusCode);

  //  The repsonse is JSON if successful and also JSON for errors.
  jsonResp := TJsonObject.Create;
  jsonResp.EmitCompact := False;
  jsonResp.Load(resp.BodyStr);

  if (resp.StatusCode <> 200) then
    begin
      //  The response body contains error information in JSON format.
      WriteLn(jsonResp.Emit());

      //  An example of an error response:
      //  		{
      //  		  "error": "access_denied",
      //  		  "error_description": "Client is not authorized to access \"https://api.example.com/geocoding/v1/\". You might probably want to create a \"client-grant\" associated to this API. See: https://auth0.com/docs/api/v2#!/Client_Grants/post_client_grants"
      //  		}
      Exit;
    end;

  WriteLn('Success!');
  WriteLn(jsonResp.Emit());

  //  A successful JSON response body looks like this:

  //  {
  //    "access_token": "eyJz93a...k4laUWw",
  //    "token_type":"Bearer",
  //    "expires_in":86400
  //  }


  json.Free;
  http.Free;
  resp.Free;
  jsonResp.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.