staples-sparx/clout

HTTP route-matching library for Clojure

Clout

Clout is a library for matching Ring HTTP requests. It uses the same routing syntax as used by popular Ruby web frameworks like Ruby on Rails and Sinatra.

Installation

Add the following to your project.clj dependencies:

[clout "1.1.0"]

Usage

These following examples make use of the ring-mock library to generate Ring request maps.

user=> (use 'ring.mock.request 'clout.core)
nil
user=> (route-matches "/article/:title"
                      (request :get "/article/clojure"))
{:title "clojure"}
user=> (route-matches "/public/*"
                      (request :get "/public/style/screen.css"))
{:* "style/screen.css"}

Clout can also match absolute routes:

user=> (route-matches "http://subdomain.example.com/"
                      (request :get "http://subdomain.example.com/"))
{}

And scheme-relative routes:

user=> (route-matches "//subdomain.example.com/"
                      (request :get "http://subdomain.example.com/"))
{}
user=> (route-matches "//subdomain.example.com/"
                      (request :get "https://subdomain.example.com/"))
{}

Clout supports both keywords and wildcards. Keywords (like ":title") will match any character but the following: / . , ; ?. Wildcards (*) will match anything.

If a route does not match, nil is returned:

user=> (route-matches "/products" "/articles")
nil

For additional performance, you can choose to pre-compile a route:

user=> (def user-route (route-compile "/user/:id"))
#'user/user-route
user=> (route-matches user-route (request :get "/user/10"))
{:id "10"}

When compiling a route, you can specify a map of regular expressions to use for different keywords. This allows more specific routing:

user=> (def user-route (route-compile "/user/:id" {:id #"\d+"}))
#'user/user-route
user=> (route-matches user-route (request :get "/user/10"))
{:user "10"}
user=> (route-matches user-route (request :get "/user/jsmith"))
nil