conf.clj

(ns datastore-api-server.conf
  "Configuration utility."
  (:use [clojure.tools.logging :only (info debug error)])
  (:use [fs.core :only (exists?)]))
  
(def DEFAULT-CONF-FILES ["server-conf.clj" "resources/server-conf.clj"])

(defn load-when 
  "If path exists, returns the data structure represented in the
   file at path. Otherwise returns nil."
  [path]
  (if (exists? path)
    (do
      (info "conf.load-when: loading conf from" path)
      (read-string (slurp path)))
    (info "conf.load-when: no file at" path "; skipping")))

(defn default-conf
  []
  (apply merge (map load-when DEFAULT-CONF-FILES)))

(def ^:dynamic *conf* (default-conf))

(defn add-file!
  "Merges the configuration in path into current *conf*. In the case of
   identical keys, the configuration in path will take precedence."
  [path]
  (def *conf* (merge *conf* (load-when path))))

; This is the primary function the application is expected to use to
; obtain final configuration data.
(defn conf [] *conf*)

(defn show 
  "Convenience fn to print conf to stdout"
  []
  (info "conf.show: conf:" (conf)))