Changes based on review 4

- Refactor to avoid using metadata.
- Expand the docstring slightly to give some indication of the expected
  return value when invalid-filename-handler is overridden.

Author: expez

ring-core/src/ring/middleware/multipart_params.clj

@@ -112,38 +112,33 @@
          func  (load-var store)]
      (func))))
 
-(defn default-invalid-filename-handler [request e]
-  (response/bad-request (.getMessage e)))
-
 (defn multipart-params-request
   "Adds :multipart-params and :params keys to request.
   See: wrap-multipart-params."
   {:added "1.2"}
   ([request]
    (multipart-params-request request {}))
   ([request options]
-   (try
-     (let [store           (or (:store options) @default-store)
-           forced-encoding (:encoding options)
-           req-encoding    (or forced-encoding
-                               (:fallback-encoding options)
-                               (req/character-encoding request)
-                               "UTF-8")
-           progress        (:progress-fn options)
-           params          (if (multipart-form? request)
-                             (parse-multipart-params request
-                                                     req-encoding
-                                                     forced-encoding
-                                                     store
-                                                     progress)
-                             {})]
-       (merge-with merge request
-                   {:multipart-params params}
-                   {:params params}))
-     (catch InvalidFileNameException e
-       (let [invalid-filename-handler
-             (:invalid-filename-handler options default-invalid-filename-handler)]
-         (with-meta (invalid-filename-handler request e) {::error? true}))))))
+   (let [store           (or (:store options) @default-store)
+         forced-encoding (:encoding options)
+         req-encoding    (or forced-encoding
+                             (:fallback-encoding options)
+                             (req/character-encoding request)
+                             "UTF-8")
+         progress        (:progress-fn options)
+         params          (if (multipart-form? request)
+                           (parse-multipart-params request
+                                                   req-encoding
+                                                   forced-encoding
+                                                   store
+                                                   progress)
+                           {})]
+     (merge-with merge request
+                 {:multipart-params params}
+                 {:params params}))))
+
+(defn default-invalid-filename-handler [request e]
+  (response/bad-request (.getMessage e)))
 
 (defn wrap-multipart-params
   "Middleware to parse multipart parameters from a request. Adds the
@@ -184,18 +179,26 @@
   - A function that gets called when the file being uploaded
     has an invalid name. The function should expect two
     parameters: request and an exception of type
-    InvalidFileNameException."
+    InvalidFileNameException. It should return a ring response."
   ([handler]
    (wrap-multipart-params handler {}))
   ([handler options]
    (fn
      ([request]
-      (let [multipart-params-request (multipart-params-request request options)]
-        (if (contains? (meta multipart-params-request) ::error?)
-          multipart-params-request
-          (handler multipart-params-request))))
+      (let [req-or-ex (try
+                        (multipart-params-request request options)
+                        (catch Exception ex ex))
+            invalid-filename-handler
+            (:invalid-filename-handler options default-invalid-filename-handler)]
+        (if (instance? Throwable req-or-ex)
+          (invalid-filename-handler request req-or-ex)
+          (handler req-or-ex))))
      ([request respond raise]
-      (let [multipart-params-request (multipart-params-request request options)]
-        (if (contains? (meta multipart-params-request) ::error?)
-          (handler multipart-params-request respond raise)
-          (respond multipart-params-request)))))))
+      (let [req-or-ex (try
+                        (multipart-params-request request options)
+                        (catch Exception ex ex))
+            invalid-filename-handler
+            (:invalid-filename-handler options default-invalid-filename-handler)]
+        (if (instance? Throwable req-or-ex)
+          (respond (invalid-filename-handler request req-or-ex))
+          (handler req-or-ex respond raise)))))))