Using mod_lua to modify request body before being sent to mod_proxy

[Matt Hughes <hughes.matt@xxxxxxxxx>]

I currently have Apache setup as a reverse proxy to another server.

I was hoping to use mod_lua to slightly tweak the request body of incoming requests before sending them off to the other server. I have mod_lua setup enough so that I have a LuaHookInsertFilter that is pointing to my LuaInputFilter. But the question is, what does the function in the LuaHookInsertFilter have to return so that the modified request continues on to the proxy?

Right now I have something like:

function handle(r)
    r.info(r, "example handler called") -- debug print
    r:add_input_filter("myInputFilter")
    return apache2.PROXYREQ_REVERSE
end

Am I using the right LuaHook? Any examples would be greatly appreciated.