More things about the blogger API...

I've reworked many times the atom template I use to post things to blogger, and what I'll describe here is a design I found simple and efficient, so here's the code :

This is the main function:

entry_new(Title, Author, { Content, ContentType }, Tags) when is_list(Tags) ->
        NTitle = post_title(Title),
        NContent = post_content(Content, ContentType),
        NTags = post_tags(Tags),
        NAuthor = post_author(Author),
        [
                entry_header(),
                NTitle,
                NContent,
                NAuthor,
                NTags,
                entry_footer()
        ];

The main idea is to use a list of binary, using this simple methods we don't mess with multiple copies or padding or strings management... This is quick and clean.

Here's some little function to create simple tempates:

entry_new(Title, Author, Content, Tags) ->
        entry_new(Title, Author, {Content, text}, Tags).

entry_header() ->
        <<"<entry xmlns=\"http://www.w3.org/2005/Atom\">">>.

entry_footer() ->
        <<"</entry>">>.
        
post_title(Title) ->
        [ <<"<title type=\"text\">">>, list_to_binary(Title), <<"</title>">> ].

post_author({ AuthorName, AuthorEmail }) ->
        [ 
        <<"<author><name>">>, list_to_binary(AuthorName), <<"</name><email>">>,
        list_to_binary(AuthorEmail), <<"</email></author>">> ];
post_author(AuthorEmail) ->
        post_author({ "", AuthorEmail }).

Here's some other function to carefully set the content-type with the post content:

post_content(Content, ContentType) when is_list(Content) ->
        post_content(list_to_binary(Content), ContentType);
post_content(Content, html) ->
        post_content(Content, "html");
post_content(Content, xhtml) ->
        post_content(Content, "xhtml");
post_content(Content, text) ->
        post_content(Content, "text");
post_content(Content, ContentType) ->
        [ <<"<content type=\"">>, list_to_binary(ContentType), <<"\">">>,
        Content,
        <<"</content>">> ].

And now the code the post 'tags':

post_tags([]) ->
        <<>>;
post_tags(List) ->
        lists:map(
                fun(X) ->
                        [ <<"<category scheme='http://www.blogger.com/atom/ns#' term='">>,
                        list_to_binary(X) ,
                        <<"'/>">> ]
                end,
                List).

The magic stands in the 'category' atom tag.