I want to make a HTTP post with TLS 1.2. I managed to make this work with Clever Internet Suite but failed with Synapse (downloaded 2025-02). I have to make a POST request in order to get a bearer (in JSON format) that I have to add in header in any following request (POST or GET).

This is used in both projects:

const 
c_username = 'AUSERNAME'; 
c_password = 'APASSWORD'; 
c_client_id= 'ACLIENTID'; 
c_url      = '';

Succeeded test with Clever Internet Suite

procedure TForm2.ButtonA2Click(Sender: TObject);
var  AHTTP:TclHttp;
     AReq:TclHttpRequest;     AItem:TclHttpRequestItem;
     s:string;   aurl,FErrorDescr:string;
     ResObj,HelpObj: TJsonObject;  FTokenLimit:TDateTime;
begin
  try
    try
      AHTTP:=TclHttp.Create(nil);     Areq:= TclHttpRequest.create(nil);
      with AHTTP do begin
        HttpVersion:=hvHttp1_1;
        TLSFlags:=[tfUseTLS12];
        UseTLS:=ctAutomatic;
      end;
      with Areq do begin
        AITem:=AReq.Items.Add(TclFormFieldRequestItem);
          with TclFormFieldRequestItem(AITem) do begin
            FieldName:='grant_type'; FieldValue:='password';
          end;
        AITem:=AReq.Items.Add(TclFormFieldRequestItem);
          with TclFormFieldRequestItem(AITem) do begin
            FieldName:='username'; FieldValue:=c_username;
          end;
        AITem:=AReq.Items.Add(TclFormFieldRequestItem);
          with TclFormFieldRequestItem(AITem) do begin
            FieldName:='password'; FieldValue:=c_password;
          end;
        AITem:=AReq.Items.Add(TclFormFieldRequestItem);
          with TclFormFieldRequestItem(AITem) do begin
            FieldName:='client_id'; FieldValue:=c_client_id;
          end;
      end;
      aurl:=c_url;
      s:=AHTTP.Post(aurl,Areq);
      Memo1.Lines.add(s);
      ResObj:=TJsonObject.Parse(s) as TJsonObject;
      if AHTTP.StatusCode = 200 then begin    
      end else begin
      end;
    except
      on E:Exception do begin
        ShowMessage(E.Message);
      end;
    end;
  finally
    AHTTP.Free;  AReq.Free;
  end;
end;

Failed test with Ararat Synapse

{ *** Notes *** 
the following DLLs (32bit, as my appl) are in application's folder: 
  libssl-1_1.dll      : v.1.1.1.23 1.1.1w    date 11.9.2023 
  libcrypto-1_1.dll   : v.1.1.1.23 1.1.1w    date 11.9.2023 
  libssl-3.dll        : v.3.4.1.0   date 11.2.2025 
  libcrypto-3.dll     : v.3.4.1.0   date 11.2.2025

What happens: MyHttpPostURL returns true (no error happened) but access is denied

> Access Denied
> You don't have permission to access "; on this server.<P> 
>> Reference #18.777ecdd4.1739735221.243974bb
>> .777ecdd4.1739735221.243974bb
}

uses 
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, 
Vcl.Controls, Vcl.Forms, Vcl.Dialogs,System.strutils,Vcl.StdCtrls,Vcl.Graphics,
HttpSend,blcksock, synautil, synaip, synacode, synsock,
ssl_openssl11, ssl_openssl11_lib 
//or (alternatively)  ssl_openssl3_lib, ssl_openssl3 

function MyHttpPostURL(const URL, URLData: string; const Data: TStream): Boolean;
{ MyHttpPostURL is exact copy of Synapse library's HttpPostUrl with the addition
  of lines:
  HTTP.protocol:='1.1';
  HTTP.Sock.SSL.SSLType:=LT_TLSv1_2;
  HTTP.UserAgent:='Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:47.0) Gecko/20100101 Firefox/47.0';
  So the WriteStrToStream procedure is Synapse original code
}
var
  HTTP: THTTPSend;
begin
  HTTP := THTTPSend.Create;
  HTTP.protocol:='1.1';
  HTTP.Sock.SSL.SSLType:=LT_TLSv1_2;
  HTTP.UserAgent:='Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:47.0) Gecko/20100101 Firefox/47.0';
  try
    WriteStrToStream(HTTP.Document, URLData);
    HTTP.MimeType := 'application/x-www-form-urlencoded';
    Result := HTTP.HTTPMethod('POST', URL);
    if Result then
      Data.CopyFrom(HTTP.Document, 0);
  finally
    HTTP.Free;
  end;
end;

procedure TForm2.SB_Auth2Click(Sender: TObject);
var MS:TMemoryStream;    URL,params:string;    AList:TStrings;
begin
  try
    MS:=TMemoryStream.create;     AList:=TStringList.Create;
    url:= c_url;
    params:='grant_type='+EncodeURLElement('password')+'&'
            +'username='+EncodeURLElement(c_username)+'&'
            +'password='+EncodeURLElement(c_password)+'&'
            +'client_id='+EncodeURLElement(c_client_id);
    try
      if MyHttpPostURL(URL, Params, MS) then begin
        Memo1.Lines.add('Boolean:true');
      end else begin
        Memo1.Lines.add('Boolean:false');
      end;
      MS.Position:=0;
      AList.LoadFromStream(MS);
      memo1.Lines.add(AList.text);
    except
      on E:Exception do begin
        ShowMessage(E.Message);
      end;
    end;
  finally
    MS.Free;   AList.Free;
  end;
end;