(Delphi DLL) Upload Media to Twitter

Demonstrates uploading image or video files to Twitter. After uploading, the media_id can be used to attach the uploaded media to a tweet.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Http, CkByteData, HttpResponse, FileAccess, JsonObject, HttpRequest;

...

procedure TForm1.Button1Click(Sender: TObject);
var
jsonToken: HCkJsonObject;
success: Boolean;
http: HCkHttp;
req: HCkHttpRequest;
fac: HCkFileAccess;
jpgBytes: HCkByteData;
resp: HCkHttpResponse;
jsonResponse: HCkJsonObject;

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

// Assume we've previously obtained an access token and saved it to a JSON file..
jsonToken := CkJsonObject_Create();
success := CkJsonObject_LoadFile(jsonToken,'qa_data/tokens/twitter.json');

http := CkHttp_Create();

// Provide the OAuth 1.0a credentials:
CkHttp_putOAuth1(http,True);
CkHttp_putOAuthConsumerKey(http,'TWITTER_CONSUMER_KEY');
CkHttp_putOAuthConsumerSecret(http,'TWITTER_CONSUMER_SECRET');
CkHttp_putOAuthToken(http,CkJsonObject__stringOf(jsonToken,'oauth_token'));
CkHttp_putOAuthTokenSecret(http,CkJsonObject__stringOf(jsonToken,'oauth_token_secret'));

req := CkHttpRequest_Create();
CkHttpRequest_putHttpVerb(req,'POST');
CkHttpRequest_putContentType(req,'multipart/form-data');
CkHttpRequest_putPath(req,'/1.1/media/upload.json');

CkHttpRequest_AddHeader(req,'Expect','100-continue');

// Add a JPEG image file to the upload.
fac := CkFileAccess_Create();
jpgBytes := CkByteData_Create();
success := CkFileAccess_ReadEntireFile(fac,'qa_data/jpg/starfish.jpg',jpgBytes);
CkHttpRequest_AddBytesForUpload(req,'media','starfish.jpg',jpgBytes);

resp := CkHttp_SynchronousRequest(http,'upload.twitter.com',443,True,req);
if (CkHttp_getLastMethodSuccess(http) <> True) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

jsonResponse := CkJsonObject_Create();
CkJsonObject_putEmitCompact(jsonResponse,False);
CkJsonObject_Load(jsonResponse,CkHttpResponse__bodyStr(resp));

if (CkHttpResponse_getStatusCode(resp) <> 200) then
  begin
    Memo1.Lines.Add(CkJsonObject__emit(jsonResponse));
    Exit;
  end;

CkHttpResponse_Dispose(resp);

// Show the successful response:
Memo1.Lines.Add(CkJsonObject__emit(jsonResponse));
Memo1.Lines.Add('Success.');

// A successful JSON response looks like this:

// 	{
// 	  "media_id": 793137045996646400,
// 	  "media_id_string": "793137045996646400",
// 	  "size": 6229,
// 	  "expires_after_secs": 86400,
// 	  "image": {
// 	    "image_type": "image\/jpeg",
// 	    "w": 120,
// 	    "h": 120
// 	  }
// 	}
// 

// Get the information from the JSON:
Memo1.Lines.Add('media_id_string = ' + CkJsonObject__stringOf(jsonResponse,'media_id_string'));
Memo1.Lines.Add('size = ' + IntToStr(CkJsonObject_IntOf(jsonResponse,'size')));
Memo1.Lines.Add('image_type = ' + CkJsonObject__stringOf(jsonResponse,'image.image_type'));
Memo1.Lines.Add('height/width = ' + IntToStr(CkJsonObject_IntOf(jsonResponse,'image.w')) + ',' + IntToStr(CkJsonObject_IntOf(jsonResponse,'image.h')));

CkJsonObject_Dispose(jsonToken);
CkHttp_Dispose(http);
CkHttpRequest_Dispose(req);
CkFileAccess_Dispose(fac);
CkByteData_Dispose(jpgBytes);
CkJsonObject_Dispose(jsonResponse);

end;