I’ve spent some time lately, playing around with the Twitter API. And along with that belongs the TwitPic’s API. I’m using Twitter a lot, to stay in touch with tech news, other developers and just for fun. But it’s getting more and more used for a lot of different things, and I needed it to integrate with an E-commerce platform I’m developing.

The code for post a picture to TwitPic looks like this:

    /// <summary>
    /// URL for the TwitPic API's upload method
    /// </summary>
    private const string TWITPIC_UPLADO_API_URL = "http://twitpic.com/api/upload";

    /// <summary>
    /// URL for the TwitPic API's upload and post method
    /// </summary>
    private const string TWITPIC_UPLOAD_AND_POST_API_URL = "http://twitpic.com/api/uploadAndPost";

    /// <summary>
    /// Uploads the photo and sends a new Tweet
    /// </summary>
    /// <param name="binaryImageData">The binary image data.</param>
    /// <param name="tweetMessage">The tweet message.</param>
    /// <param name="filename">The filename.</param>
    /// <returns>Return true, if the operation was succeded.</returns>
    public bool UploadPhoto(byte[] binaryImageData, string tweetMessage, string filename)
    {
      // Documentation: http://www.twitpic.com/api.do
      string boundary = Guid.NewGuid().ToString();
      string requestUrl = String.IsNullOrEmpty(tweetMessage) ? TWITPIC_UPLADO_API_URL : TWITPIC_UPLOAD_AND_POST_API_URL;
      HttpWebRequest request = (HttpWebRequest)WebRequest.Create(requestUrl);
      string encoding = "iso-8859-1";

      request.PreAuthenticate = true;
      request.AllowWriteStreamBuffering = true;
      request.ContentType = string.Format("multipart/form-data; boundary={0}", boundary);
      request.Method = "POST";

      string header = string.Format("--{0}", boundary);
      string footer = string.Format("--{0}--", boundary);

      StringBuilder contents = new StringBuilder();
      contents.AppendLine(header);

      string fileContentType = GetImageContentType(filename);
      string fileHeader = String.Format("Content-Disposition: file; name=\"{0}\"; filename=\"{1}\"", "media", filename);
      string fileData = Encoding.GetEncoding(encoding).GetString(binaryImageData);

      contents.AppendLine(fileHeader);
      contents.AppendLine(String.Format("Content-Type: {0}", fileContentType));
      contents.AppendLine();
      contents.AppendLine(fileData);

      contents.AppendLine(header);
      contents.AppendLine(String.Format("Content-Disposition: form-data; name=\"{0}\"", "username"));
      contents.AppendLine();
      contents.AppendLine(this.Username);

      contents.AppendLine(header);
      contents.AppendLine(String.Format("Content-Disposition: form-data; name=\"{0}\"", "password"));
      contents.AppendLine();
      contents.AppendLine(this.Password.ToInsecureString());

      if (!String.IsNullOrEmpty(tweetMessage))
      {
        contents.AppendLine(header);
        contents.AppendLine(String.Format("Content-Disposition: form-data; name=\"{0}\"", "message"));
        contents.AppendLine();
        contents.AppendLine(tweetMessage);
      }

      contents.AppendLine(footer);

      byte[] bytes = Encoding.GetEncoding(encoding).GetBytes(contents.ToString());
      request.ContentLength = bytes.Length;

      using (Stream requestStream = request.GetRequestStream())
      {
        requestStream.Write(bytes, 0, bytes.Length);

        using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
        {
          using (StreamReader reader = new StreamReader(response.GetResponseStream()))
          {
            string result = reader.ReadToEnd();

            XDocument doc = XDocument.Parse(result);

            XElement rsp = doc.Element("rsp");
            string status = rsp.Attribute(XName.Get("status")) != null ? rsp.Attribute(XName.Get("status")).Value : rsp.Attribute(XName.Get("stat")).Value;

            return status.ToUpperInvariant().Equals("OK");
          }
        }
      }
    }