Yet another blog engine#

Mon Feb 16 21:35:11 2015

Yablog is the unimaginatively named "Yet Another Blog engine" and is what's now behind the blog at ww.telent.net - mostly because every third attempt to post with my-way ended up with having to relearn out how all the baroque git hooks worked.

It was supposed to be a two-hour Tuesday morning hack, but it's now almost the following Tuesday morning as I did not anticipate that

• I would need to write my own Textile parser (see https://github.com/telent/texticlj )

• I would need to write my own date parser (see https://github.com/telent/yablog/blob/master/src/yablog/time.clj and https://github.com/telent/yablog/blob/master/resources/dates.bnf ). Instaparse is awesome, it took less time to do this than it was taking to find and download other people's date parsers and find that they didn't support all the date formts I needed to parse

• I would get sucked into the fiddling-around-with-CSS vortex

This entry is mostly just a placeholder to check the new posting process works, but do check out Instaparse if you haven't used it already.

Regaining my compojure#

Thu Feb 19 10:16:22 2015

Picking up $secret_project which I put down in November to do Sledge and Yablog, I find that the routing of http requests is a horrendous mess based on substring matching and ad hoc argument parsing, and would really benefit from some Compojure

(Now, that is, that I've actually got my head around how Compojure works)

Because I'm using Hiccup to compose pages out of parts, I thought it would be neat if I could return hiccup page bodies directly as responses so that they get uniformly topped and tailed and turned into response maps. Turns out to be fairly straightforward:

1. define a type for the hiccup response
2. extend the compojure.response/Renderable protocol to deal with the new type

(deftype Hiccupage [body])
 
(defn page-surround [page]
  (let [head [:head
              [:link {:rel "stylesheet" :type "text/css"
                      :href "/static/default.css"}]
              [:script {:src "/static/stuff.js"}]
              [:title "Hey you"]]]
    (into head (.body page))))
 
(extend-protocol compojure.response/Renderable
  Hiccupage
  (render [page req]
    {:status  200
     :headers {"Content-Type" "text/html; charset=utf-8"}
     :body   (hiccup.page/html5 (page-surround page))}))

Now we can return Hiccupage (hiccup page? geddit? I'm still looking for a better name, yes) objects directly from our routes

(defroutes app
    (GET "/hello/:name" [name] 
	 (Hiccupage.
	  [[:h1 "hello"]
	   [:p "hello " name]
	   [:p "This is text. I like text"]]))
  ...
  )