Delphi ActiveX

WhatsApp - Send a Previously Uploaded Media Message

Demonstrates how to send a media message where the media content was previously uploaded. 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;
http: TChilkatHttp;
json: TChilkatJsonObject;
resp: TChilkatHttpResponse;
sbResponseBody: TChilkatStringBuilder;
jResp: TChilkatJsonObject;
respStatusCode: Integer;
id: WideString;
i: Integer;
count_i: Integer;

begin
success := 0;

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

http := TChilkatHttp.Create(Self);

// Implements the following CURL command:

// curl -X POST https://example.com/v1/messages \
//   -H "Authorization: Bearer your-auth-token" \
//   -d '
// {
//     "recipient_type": "individual-or-group",
//     "to": "whatsapp-id-or-group-id",
//     "type": "image",
//     "image": {
//      "id": "your-media-id",
//       "caption": "your-image-caption"
//     }
// }'

// 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.

// {
//   "recipient_type": "individual-or-group",
//   "to": "whatsapp-id-or-group-id",
//   "type": "image",
//   "image": {
//     "id": "your-media-id",
//     "caption": "your-image-caption"
//   }
// }

json := TChilkatJsonObject.Create(Self);
json.UpdateString('recipient_type','individual-or-group');
json.UpdateString('to','whatsapp-id-or-group-id');
json.UpdateString('type','image');
json.UpdateString('image.id','your-media-id');
json.UpdateString('image.caption','your-image-caption');

// Adds the "Authorization: Bearer your-auth-token" header.
http.AuthToken := 'your-auth-token';

resp := TChilkatHttpResponse.Create(Self);
success := http.HttpJson('POST','https://example.com/v1/messages',json.ControlInterface,'application/json',resp.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(http.LastErrorText);
    Exit;
  end;

sbResponseBody := TChilkatStringBuilder.Create(Self);
resp.GetBodySb(sbResponseBody.ControlInterface);
jResp := TChilkatJsonObject.Create(Self);
jResp.LoadSb(sbResponseBody.ControlInterface);
jResp.EmitCompact := 0;

Memo1.Lines.Add('Response Body:');
Memo1.Lines.Add(jResp.Emit());

respStatusCode := resp.StatusCode;
Memo1.Lines.Add('Response Status Code = ' + IntToStr(respStatusCode));
if (respStatusCode >= 400) then
  begin
    Memo1.Lines.Add('Response Header:');
    Memo1.Lines.Add(resp.Header);
    Memo1.Lines.Add('Failed.');
    Exit;
  end;

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

// {
//   "messages": [
//     {
//       "id": "gBEGkYiEB1VXAglK1ZEqA1YKPrU"
//     }
//   ]
// }

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

i := 0;
count_i := jResp.SizeOfArray('messages');
while i < count_i do
  begin
    jResp.I := i;
    id := jResp.StringOf('messages[i].id');
    i := i + 1;
  end;
end;