Webmachine Post and Redirect

I've just started a new project using an Erlang backend that is built on the Basho Webmachine system.

I'm really loving the RESTful nature of Webmachine, but must admit it did take me a little while to figure out how to return a 403 redirect from a POST. I found the odd blog post (here and here) that sort of did what I wanted but not quite. Eventually, after a bit of debugging and much consulatation of The Diagram I came up with the following.

allow_missing_post(ReqData, State) ->
    {true, ReqData, State}.

post_is_create(ReqData, State) ->
    {true, ReqData, State}.

create_path(ReqData, State) ->
    {"/my_redirect_location", ReqData, State}.

content_types_accepted(ReqData, State) ->
    {[{"application/x-www-form-urlencoded", process_form}], ReqData, State}.

process_form(ReqData, State) ->
    %% do stuff
    {true, wrq:do_redirect(true, ReqData), State};      

So I think you need to have the allow_missing_post and post_is_create functions return true and the create_path function return the path you want to redirect to.

Then you need to have the content type mapped to a handler function which calls the request modification function "do_redirect".

Oh, also I'm probably reinventing the wheel (and probably badly) but I wrote my a couple of functions to turn a POSTed form into a proplist for processing in the handler.

parse_form_body(FormBody) ->
    Tokens = binary:split(FormBody, <<"&">>, [global]),
    lists:foldl(fun(X, Acc) -> add_to_proplist(X, Acc) end, [], Tokens).

add_to_proplist(Item, Items) ->
    [Key, Value] = binary:split(Item, <<"=">>, [global]),
    [{Key, Value}|Items].