CSS fails with extended paths in Compojure / Hiccup

Question

I've been converting some Noir websites to Compojure.

I have a function here that creates the layout of the page:

(defn layout [title & content]
  (html5
   [:head
    [:title "My Site | " title]
    (include-css "css/main.css")
   [:body
    [:header 
     [:h1 (link-to "/" "My Site")]]
    content]))

And this is the function and the routes:

(defn home-page []
  (layout
   "Home"
   [:div [:p "Home Page"]])))

(defn article-list []
  (layout
   "Article List"
   [:div [:p "Article List"]])))

(defroutes app-routes
  (GET "/" [] (home-page))
  (GET "/article-list" [] (article-list))

When I open up localhost:3000/article-list all of the CSS rules work fine.

However, when I attempt to extend the URL path and change the program to:

(defn article-list []
  (layout
   "Article List"
   [:div [:p "Article List"]])))

(defn article-one []
  (layout
   "Article One"
   [:div [:p "Article One"]])))

(defroutes app-routes
  (GET "/" [] (home-page))
  (GET "/article-list" [] (article-list)
  (GET "/article-list/article-one" [] (article-one))

And go to localhost:3000/article-list/article-one, I get all of the HTML but the CSS rules no longer work. When I inspect the page, the css paths are included in the < head > element but there are no styles on the page.

I've searched for a solution to this issue, but there doesn't seem to be any writing on this. I've also tried pulling out the routes so that I have:

(defroutes article-routes
  (GET "/article-list/article-one" [] (article-one))

(defroutes app-routes
  (GET "/" [] (home-page))
  (GET "/article-list" [] (article-list)
  (context "article-list" [] article-routes)

but I have the same issue. How can I get the CSS rules to work on pages with extended paths?

Answer 1

Your CSS is being included with a relative path, which means the when you go to localhost:3000/article-list/article-one your browser is looking for the CSS at localhost:3000/article-list/css/main.css.

The easiest way to fix this would be to include the CSS with (include-css "/css/main.css"). The / at the beginning will ensure it always searches for localhost:3000/css/main.css.