Delphi ActiveX

Debug REST HTTP Request

See more REST Examples

Demonstrates how to generate the HTTP Request (with all headers intact) without actually sending the request.

Note: This example requires Chilkat v9.5.0.77 or later.

Delphi ActiveX

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Integer;
rest: TChilkatRest;
bTls: Integer;
port: Integer;
bAutoReconnect: Integer;
json: TChilkatJsonObject;
sbRequestBody: TChilkatStringBuilder;
sbResponseBody: TChilkatStringBuilder;
bdRequest: TChilkatBinData;

begin
success := 0;

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

// This example will connect to the web server, but does not actually send a request.
// When in DebugMode, the request is composed in memory and can be retrieved by calling
// GetLastDebugRequest.

rest := TChilkatRest.Create(Self);

// Connect Code...
// URL: https://test-api.service.hmrc.gov.uk/organisations/vat/MY_HMRC_VRN/returns
bTls := 1;
port := 443;
bAutoReconnect := 1;
success := rest.Connect('test-api.service.hmrc.gov.uk',port,bTls,bAutoReconnect);
if (success <> 1) then
  begin
    Memo1.Lines.Add('ConnectFailReason: ' + IntToStr(rest.ConnectFailReason));
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// Build the request body...
json := TChilkatJsonObject.Create(Self);
json.UpdateString('periodKey','A001');
json.UpdateNumber('vatDueSales','105.50');
json.UpdateNumber('vatDueAcquisitions','-100.45');
json.UpdateNumber('totalVatDue','5.05');
json.UpdateNumber('vatReclaimedCurrPeriod','105.15');
json.UpdateNumber('netVatDue','100.10');
json.UpdateInt('totalValueSalesExVAT',300);
json.UpdateInt('totalValuePurchasesExVAT',300);
json.UpdateInt('totalValueGoodsSuppliedExVAT',3000);
json.UpdateInt('totalAcquisitionsExVAT',3000);
json.UpdateBool('finalised',1);

// Add Headers...
rest.AddHeader('Accept','application/vnd.hmrc.1.0+json');
rest.AddHeader('Authorization','Bearer HMRC_ACCESS_TOKEN');
rest.AddHeader('Content-Type','application/json');

sbRequestBody := TChilkatStringBuilder.Create(Self);
json.EmitSb(sbRequestBody.ControlInterface);

// Set DebugMode so that no request is actually sent.
rest.DebugMode := 1;

sbResponseBody := TChilkatStringBuilder.Create(Self);
success := rest.FullRequestSb('POST','/organisations/vat/MY_HMRC_VRN/returns',sbRequestBody.ControlInterface,sbResponseBody.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// Get the exact contents of what would've been sent.
// This includes the HTTP start line, the HTTP request headers, and the request body.
// Given that it's possible for the request body to contain binary data,
// the GetLastDebugRequest fetches into a BinData object.
// In this case, however, our request body contained JSON, so we can
// examine it as a string..
bdRequest := TChilkatBinData.Create(Self);
success := rest.GetLastDebugRequest(bdRequest.ControlInterface);

Memo1.Lines.Add('----');
Memo1.Lines.Add(bdRequest.GetString('utf-8'));
Memo1.Lines.Add('----');

// The output for the above case:

// POST /organisations/vat/MY_HMRC_VRN/returns HTTP/1.1
// Accept: application/vnd.hmrc.1.0+json
// Host: test-api.service.hmrc.gov.uk
// Authorization: Bearer HMRC_ACCESS_TOKEN
// Content-Type: application/json
// Content-Length: 281
// 
// {"periodKey":"A001","vatDueSales":105.50, ... ,"finalised":true}
// 
// 
end;