Deprecated individual config variables in favour of a config map.

README.md

@@ -62,21 +62,21 @@ For example:
 (get-message :pipe "de-DE" "i18n" "ru")
 ```
 
-So how does this work? When one calls `(get-message token accept-language-header)`, how does it know where to find resources? The answer is that there are two dynamic variables:
+So how does this work? When one calls 
+`(get-message token accept-language-header)`, how does it know where to find resources? The answer is that there is a `*config*` map, with (currently) two significant keys:
 
-* `*resource-path*`, the default path within the resources space on which 
-   translation files will be sought. Initialised to `i18n`.
-* `*default-language*`, the language tag for the language to use when no
+* `:resource-path`, whose value should be a string representation of the default 
+   path within the resources space on which translation files will be sought. Initialised to `i18n`.
+* `:default-language`, the language tag for the language to use when no
    otherwise suitable language can be identified. Initialised to the default
    language of the runtime session, so this may well be different on your 
    machine from someone elses running identical software.
 
 Thus
 ```clojure
-(binding [*resource-path* "language-files"
-          *default-language* "en-CA"]
-    (get-message :pipe "en-GB;q=0.9, fr-FR")
-)
+(binding [*config* {:resource-path "language-files"
+                    :default-language "en-CA"}]
+    (get-message :pipe "en-GB;q=0.9, fr-FR"))
 ```
 and
 ```clojure
@@ -116,10 +116,27 @@ In this project you will find two very simple example files, which should give y
 
 ## Documentation
 
-Documentation may be generated by running
+Documentation can be found here. It may be generated by running
 
     lein codox
 
+## Future direction
+
+It's likely that in future configuration will be extended
+
+1. To read per-language keys/messages from CSV files;
+2. To read per-language keys/messages from database tables;
+3. potentially, to read per-language keys/messages from other sources.
+
+Pull requests implementing any of these things will be welcomed.
+
+## Deprecated features
+
+There are still two dynamic configuration variables, `*default-language*` 
+and `*resource-path*`, but these are now superceded by the `*config*` map,
+which is extensible. Consequently, if you are using these configuration 
+variables in production, you should bind `*config*` to `nil`.
+
 ## License
 
 Copyright © 2017 Simon Brooke

resources/i18n/en-GB.edn

@@ -1,3 +1,3 @@
 ;;;; This is a British English translation file.
 
-{:pipe "This is not a pipe"}
+{:pipe "This is not a pipe."}

src/scot/weft/i18n/core.clj

@@ -22,13 +22,18 @@
 
 (def ^:dynamic *resource-path*
   "The default path within the resources space on which translation files 
-   will be sought."
+   will be sought. Deprecated, prefer `(:resource-path *config*)`."
   "i18n")
 
 (def ^:dynamic *default-language*
-  "The default language to seek."
+  "The default language to seek. Deprecated, prefer `(:default-language *config*)`."
   (-> (locale/get-default) locale/to-language-tag))
 
+(def ^:dynamic *config*
+  "Extensible configuration for i18n."
+  {:default-language (-> (locale/get-default) locale/to-language-tag)
+   :resource-path "i18n"})
+
 (def accept-language-grammar
   "Grammar for `Accept-Language` headers"
   "HEADER := SPECIFIER | SPECIFIERS;
@@ -218,9 +223,13 @@
    * `default-locale` should be a locale specifier to use if no acceptable locale can be
      identified."
   (fn ([^Keyword token ^String accept-language-header ^String resource-path ^String default-locale]
-       (let [message ((get-messages accept-language-header resource-path default-locale) token)]
+       (let [message (token (get-messages accept-language-header resource-path default-locale))]
          (or message (name token))))
     ([^Keyword token ^String accept-language-header]
-     (get-message token accept-language-header *resource-path* *default-language*))
+     (get-message token 
+                  accept-language-header 
+                  (or (:resource-path *config*) *resource-path*) 
+                  (or (:default-language *config*) *default-language*)))
     ([^Keyword token]
-     (get-message token *default-language* *resource-path* *default-language*))))
+     (get-message token 
+                  (or (:default-language *config*) *default-language*)))))

test/scot/weft/i18n/test/core.clj

@@ -1,7 +1,8 @@
 (ns ^{:doc "Tests for Internationalisation."
       :author "Simon Brooke"} scot.weft.i18n.test.core
   (:require [clojure.test :refer [deftest is testing]]
-            [scot.weft.i18n.core :refer [*default-language*
+            [scot.weft.i18n.core :refer [*config*
+                                         *default-language*
                                          acceptable-languages
                                          generate-accept-languages
                                          get-message
@@ -206,7 +207,7 @@
   (testing "Top level functionality"
     (is
      (=
-      "This is not a pipe"
+      "This is not a pipe."
       (:pipe (get-messages "en-GB, fr-FR;q=0.9" "i18n" "en-GB"))))
     (is
      (=
@@ -215,10 +216,25 @@
     (is
      (= nil (get-messages "xx-XX;q=0.5, yy-YY" "i18n" "zz-ZZ"))
      "If no usable file is found, an exception should not be thrown.")
-    (binding [*default-language* "en-GB"]
-      (is (= "This is not a pipe" (get-message :pipe)))
+    (binding [*config* (assoc *config* :default-language "fr-FR")]
+      (is (= "Ceci n'est pas une pipe." (get-message :pipe)))
       (is
        (=
-        "Ceci n'est pas une pipe." (get-message :pipe "en-GB;q=0.9, fr-FR")))
+        "This is not a pipe." (get-message :pipe "en-GB, fr-FR;q=0.9")))
       (is (= "это не труба." (get-message :pipe "de-DE" "i18n" "ru")))
-      (is (= "froboz" (get-message :froboz))))))
+      (is (= "froboz" (get-message :froboz)))))
+  (testing "Final fall through if no suitable language found"
+    (binding [*config* (assoc *config* :default-language "de-DE")]
+      ;; there is no 'de-DE' language resource in the resources, 
+      ;; and that's exactly why we've chosen it for this test.
+      (is (= "pipe" (get-message :pipe)))))
+  (testing "Deprecated variables still work"
+    (binding [*config* nil
+              *default-language* "en-GB"]
+      (is (= "This is not a pipe." (get-message :pipe)))
+      (is
+       (= "Ceci n'est pas une pipe."
+          (get-message :pipe "en-GB;q=0.9, fr-FR"))))
+    (binding [*config* nil
+              *default-language* "ru"]
+      (is (= "это не труба." (get-message :pipe))))))