Add set-system-proxy\! function, allowing the use of a proxy server in HTTP requests.

Author: Richard Newman

src/clojure/http/client.clj

@@ -9,6 +9,16 @@
                                         " (+http://clojure.org)"),
                       "Connection" "close"})
 
+(defn set-system-proxy!
+  "Java's HttpURLConnection cannot do per-request proxying. Instead,
+  system properties are used. This function mutates the global setting.
+  For per-request proxying, use the Apache HTTP client."
+  [#^String host port]
+  (doto (System/getProperties)
+    (.setProperty "http.proxyHost" host)
+    (.setProperty "http.proxyPort" (str port)))
+  nil)
+  
 (defn url-encode
   "Wrapper around java.net.URLEncoder returning a (UTF-8) URL encoded
 representation of argument, either a string or map."