Pascal (Lazarus/Delphi)

OpenAI (ChatGPT) Create Chat Completion

See more OpenAI ChatGPT Examples

Shows how to create a model response for a given chat conversation. 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.HttpResponse,
  Chilkat.JsonObject;

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

procedure RunDemo;
var
  success: Boolean;
  http: THttp;
  json: TJsonObject;
  resp: THttpResponse;
  sbResponseBody: TStringBuilder;
  jResp: TJsonObject;
  respStatusCode: Integer;
  index: Integer;
  Role: string;
  Content: string;
  finish_reason: string;
  id: string;
  v_object: string;
  created: Integer;
  Prompt_tokens: Integer;
  Completion_tokens: Integer;
  Total_tokens: Integer;
  i: Integer;
  count_i: 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;

  //  Implements the following CURL command:

  //  curl https://api.openai.com/v1/chat/completions \
  //    -H "Content-Type: application/json" \
  //    -H "Authorization: Bearer $OPENAI_API_KEY" \
  //    -d '{
  //      "model": "gpt-3.5-turbo",
  //      "messages": [{"role": "user", "content": "Hello!"}]
  //    }'

  //  Use the following online tool to generate HTTP code from a CURL command
  //  Convert a cURL Command to HTTP Source Code

  //  Use this online tool to generate code from sample JSON:
  //  Generate Code to Create JSON

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

  //  {
  //    "model": "gpt-3.5-turbo",
  //    "messages": [
  //      {
  //        "role": "user",
  //        "content": "Hello!"
  //      }
  //    ]
  //  }

  json := TJsonObject.Create;
  json.UpdateString('model','gpt-3.5-turbo');
  json.UpdateString('messages[0].role','user');
  json.UpdateString('messages[0].content','Hello!');

  //  Adds the "Authorization: Bearer $OPENAI_API_KEY" header.
  //  This is NOT a real key.  Change the "sk-vi...." to your own key.
  http.AuthToken := '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';
  http.SetRequestHeader('Content-Type','application/json');

  resp := THttpResponse.Create;
  success := http.HttpJson('POST','https://api.openai.com/v1/chat/completions',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)

  //  {
  //    "id": "chatcmpl-123",
  //    "object": "chat.completion",
  //    "created": 1677652288,
  //    "choices": [
  //      {
  //        "index": 0,
  //        "message": {
  //          "role": "assistant",
  //          "content": "\n\nHello there, how may I assist you today?"
  //        },
  //        "finish_reason": "stop"
  //      }
  //    ],
  //    "usage": {
  //      "prompt_tokens": 9,
  //      "completion_tokens": 12,
  //      "total_tokens": 21
  //    }
  //  }

  //  Sample code for parsing the JSON response...
  //  Use the following online tool to generate parsing code from sample JSON:
  //  Generate Parsing Code from JSON

  id := jResp.StringOf('id');
  v_object := jResp.StringOf('object');
  created := jResp.IntOf('created');
  Prompt_tokens := jResp.IntOf('usage.prompt_tokens');
  Completion_tokens := jResp.IntOf('usage.completion_tokens');
  Total_tokens := jResp.IntOf('usage.total_tokens');
  i := 0;
  count_i := jResp.SizeOfArray('choices');
  while i < count_i do
    begin
      jResp.I := i;
      index := jResp.IntOf('choices[i].index');
      Role := jResp.StringOf('choices[i].message.role');
      Content := jResp.StringOf('choices[i].message.content');
      finish_reason := jResp.StringOf('choices[i].finish_reason');
      i := i + 1;
    end;



  http.Free;
  json.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.