From Googerl to googleatom_app

Hi, (a quick post)
I've been busy this weekend working on a more generic layer for google API. Here comes the 'googleatom_app'.

I've uploaded it in the googerl project.
The application needs 'crypto, ssl, inets' to work.

[ application:start(X) || X <- [crypto, ssl, inets, googleatom] ]

should start the application.
There's currently not much documentation, this is still at a very early stage. Here's a list of what you can do now:

• Post an article into blogger
• Post a photo into picasa, taken from a file or from a URL (inets download the image and send it to picasa)

Once the application has started, you'll see two new registered processes 'blogger_srv' and 'picasa_srv'. The first thing you need to do before being able to use thoses process is setting your google credentials:

picasa_srv:auth(Username, Password).

Once the call returns you'll receive a google token string. If not you'll have to investigate a little :).
Ok now that you're authenticated you can post a nice photo into your gallery:

picasa_srv:new(Username, Album, "http://www.aniceimageservier.com/superimage.jpg", "Fake Image Name").

Since the process of posting images takes time, picasa_srv uses 'gen_server:cast', and now the success is indicated by some 'error_logger:info_msg' ... (xmerl is used to extract various new urls of your posted photo).

That's it for this really quick introduction, I'll will update files within days, actually some funs are not available everywhere, I'll fix this.

I'll post a googleatom_app tutorial later this week...

Erlang Picasa API, it works, and here's some reason why...

The Post request to the picasa web service:

request_picasa(AuthToken, User, ImgName, Data) ->
     Body = iolist_to_binary(Data),
     Authorization = <<"GoogleLogin auth=", AuthToken/binary>>,
     Url = "http://picasaweb.google.com/data/feed/api/user/" ++ User ++ "/album/blog",
     case http:request(post,
                     {       Url,
                             [ { "Authorization", binary_to_list(Authorization) },
                               { "Slug", ImgName }
                             ],
                             "image/jpeg",                           % Content-type
                             Body                                    % Body
                     },
             [ {timeout, 30000}, {sync, false} ],            % HTTPOptions
             [ {body_format, binary} ]) of                   % Options

             {ok, Result} ->
                     case Result of
                             {{_, 201, _}, Headers, Response} ->
                                     {ok, Headers, Response};

                             {_,_,Response} ->
                                     Response
                     end;

             {error, Reason} ->
                     io:format("Error: ~p~n", [Reason])
     end.

And what's you must note is the following:

• a new url to Post your image.
• a new header named 'Slug' holding the value of the filename you want for your image
• a timeout of 30 seconds, letting enough time for the upload process to complete.

Other headers are mandatory, and hopefully already set by 'http:request':

• content-length holding the size of the binary data of your image
• content-type holding the image type, here 'image/jpeg'

I choose to use the 'prim_file:load_file/1' fun to retrieve a binary stream of octet composing the image I want to upload:

      {ok, File} = prim_file:read_file(Image),
      {value, {_, Auth}} = lists:keysearch(picasa, 1, State#state.auth),
      case request_picasa(Auth, User, ImgName, File ) of

The variable File holds the binary data, the Auth variable holds the 'correct' Picasa AuthToken, so the 'request_picasa/4' fun can be called correctly...

I'll upgrade later the project http://code.google.com/p/googerl, because I want the 'request_picasa' fun to return {ok, ImageUrl}, and to do that I need to parse the atom response sent by Google... And I'm asking myself wether I doit using xmerl or leex ;]