Merge pull request #49 from rjack/parse-params-exposed

Refactor parameter parsing

@@ -1,6 +1,6 @@
 (ns ring.middleware.multipart-params
   "Parse multipart upload into params."
-  (:use [ring.middleware.params :only (assoc-param)])
+  (:use [ring.util.codec :only (assoc-param)])
   (:import [org.apache.commons.fileupload.util Streams]
            [org.apache.commons.fileupload
              RequestContext

@@ -1,38 +1,13 @@
 (ns ring.middleware.params
   "Parse form and query params."
-  (:require [ring.util.codec :as codec]
-            [clojure.string :as string]))
-
-(defn assoc-param
-  "Associate a key with a value. If the key already exists in the map,
-  create a vector of values."
-  [map key val]
-  (assoc map key
-    (if-let [cur (map key)]
-      (if (vector? cur)
-        (conj cur val)
-        [cur val])
-      val)))
-
-(defn- parse-params
-  "Parse parameters from a string into a map."
-  [^String param-string encoding]
-  (reduce
-    (fn [param-map encoded-param]
-      (if-let [[_ key val] (re-matches #"([^=]+)=(.*)" encoded-param)]
-        (assoc-param param-map
-          (codec/url-decode key encoding)
-          (codec/url-decode (or val "") encoding))
-         param-map))
-    {}
-    (string/split param-string #"&")))
+  (:require [ring.util.codec :as codec]))
 
 (defn- assoc-query-params
   "Parse and assoc parameters from the query string with the request."
   [request encoding]
   (merge-with merge request
     (if-let [query-string (:query-string request)]
-      (let [params (parse-params query-string encoding)]
+      (let [params (codec/form-decode query-string encoding)]
         {:query-params params, :params params})
       {:query-params {}, :params {}})))
 
@@ -47,7 +22,7 @@
   [request encoding]
   (merge-with merge request
     (if-let [body (and (urlencoded-form? request) (:body request))]
-      (let [params (parse-params (slurp body :encoding encoding) encoding)]
+      (let [params (codec/form-decode (slurp body :encoding encoding) encoding)]
         {:form-params params, :params params})
       {:form-params {}, :params {}})))
 

@@ -2,7 +2,8 @@
   "Encoding and decoding utilities."
   (:import java.io.File
            (java.net URLEncoder URLDecoder)
-           org.apache.commons.codec.binary.Base64))
+           org.apache.commons.codec.binary.Base64)
+  (:require [clojure.string :as string]))
 
 (defn url-encode
   "Returns the form-url-encoded version of the given string, using either a
@@ -27,3 +28,49 @@
   "Decode a base64 encoded string into an array of bytes."
   [^String encoded]
   (Base64/decodeBase64 (.getBytes encoded)))
+
+(defn assoc-param
+  "Associate a key with a value. If the key already exists in the map,
+  create a vector of values."
+  [map key val]
+  (assoc map key
+    (if-let [cur (map key)]
+      (if (vector? cur)
+        (conj cur val)
+        [cur val])
+      val)))
+
+(defn form-decode
+  "Parse parameters from a string into a map."
+  ([^String param-string]
+     (form-decode param-string "UTF-8"))
+  ([^String param-string encoding]
+     (reduce
+      (fn [param-map encoded-param]
+        (if-let [[_ key val] (re-matches #"([^=]+)=(.*)" encoded-param)]
+          (assoc-param param-map
+                       (url-decode key encoding)
+                       (url-decode (or val "") encoding))
+          param-map))
+      {}
+      (string/split param-string #"&"))))
+
+(defn form-encode
+  "Encode parameters from a map into a string."
+  ([param-map]
+     (form-encode param-map "UTF-8"))
+  ([param-map encoding]
+     (form-encode (keys param-map)
+                  (vals param-map)
+                  encoding))
+  ([params values encoding]
+     (string/join #"&"
+                  (map (fn [param value]
+                         (if (vector? value)
+                           (form-encode (repeat (count value) param)
+                                        value
+                                        encoding)
+                           (str (url-encode param)
+                                "="
+                                (url-encode value))))
+                       params values))))

@@ -17,3 +17,11 @@
 (deftest test-base64-encoding
   (let [str-bytes (.getBytes "foo?/+" "UTF-8")]
     (is (Arrays/equals str-bytes (base64-decode (base64-encode str-bytes))))))
+
+(deftest form-encoding
+  (let [encoded-params "p%2F1=v%2F1&p%2F2=v%2F21&p%2F2=v%2F22"]
+    (is (= (form-decode encoded-params)
+           (-> encoded-params
+               form-decode
+               form-encode
+               form-decode)))))