add support for proxy servers

src/main/java/io/keen/client/java/KeenConfig.java

@@ -1,5 +1,8 @@
 package io.keen.client.java;
 
+import java.net.InetSocketAddress;
+import java.net.Proxy;
+
 /**
  * KeenConfig
  *
@@ -10,9 +13,30 @@
  */
 public class KeenConfig {
 
+    private static Proxy proxy;
     /**
      * How many threads to use to send events to Keen IO. Change this to 0 if you want to manage your own threads.
      */
     public static int NUM_THREADS_FOR_HTTP_REQUESTS = 3;
 
+    /**
+     * Call this to set a HTTP proxy server configuration for all Keen IO communication.
+     *
+     * @param proxyUrl The proxy hostname or IP address.
+     * @param proxyPort  The proxy port number.
+     */
+    public static void setProxy(String proxyUrl, int proxyPort) {
+        proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress(proxyUrl, proxyPort));
+    }
+
+    static Proxy getProxy() {
+        return proxy;
+    }
+
+    /**
+     * Call this to clean the currently configured HTTP Proxy server configuration.
+     */
+    public static void clearProxy() {
+        proxy = null;
+    }
 }

src/main/java/io/keen/client/java/KeenHttpRequestRunnable.java

@@ -4,6 +4,7 @@
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.net.HttpURLConnection;
+import java.net.Proxy;
 import java.net.URL;
 import java.util.Map;
 
@@ -21,12 +22,18 @@ class KeenHttpRequestRunnable implements Runnable {
     private final String eventCollection;
     private final Map<String, Object> event;
     private final AddEventCallback callback;
+    private final Proxy proxy;
 
     KeenHttpRequestRunnable(KeenClient keenClient, String eventCollection, Map<String, Object> event, AddEventCallback callback) {
+        this(keenClient,eventCollection,event,callback,KeenConfig.getProxy());
+    }
+
+    KeenHttpRequestRunnable(KeenClient keenClient, String eventCollection, Map<String, Object> event, AddEventCallback callback, Proxy proxy) {
         this.keenClient = keenClient;
         this.eventCollection = eventCollection;
         this.event = event;
         this.callback = callback;
+        this.proxy = proxy;
     }
 
     @Override
@@ -56,7 +63,7 @@ HttpURLConnection sendEvent(String eventCollection, Map<String, Object> event) t
         URL url = new URL(urlString);
 
         // set up the POST
-        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+        HttpURLConnection connection = openConnection(url);
         connection.setRequestMethod("POST");
         connection.setRequestProperty("Accept", "application/json");
         connection.setRequestProperty("Content-Type", "application/json");
@@ -72,6 +79,13 @@ HttpURLConnection sendEvent(String eventCollection, Map<String, Object> event) t
         return connection;
     }
 
+    HttpURLConnection openConnection(URL url) throws IOException {
+        if(proxy == null){
+            return (HttpURLConnection) url.openConnection();
+        }
+        return (HttpURLConnection)url.openConnection(proxy);
+    }
+
     static void handleResult(InputStream input, int responseCode, AddEventCallback callback) {
         if (responseCode == 201) {
             // event add worked

src/test/java/io/keen/client/java/KeenConfigTest.java

@@ -0,0 +1,37 @@
+package io.keen.client.java;
+
+import org.junit.After;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+public class KeenConfigTest {
+
+    @After
+    public void tearDown() throws Exception {
+        KeenConfig.clearProxy();
+    }
+
+    @Test
+    public void proxyStartOffEmpty() throws Exception {
+        assertNull(KeenConfig.getProxy());
+    }
+
+    @Test
+    public void canConfigureProxyObject() throws Exception {
+
+        KeenConfig.setProxy("foo", 8080);
+
+        assertEquals("foo:8080", KeenConfig.getProxy().address().toString());
+    }
+
+    @Test
+    public void canClearProxy() throws Exception {
+        KeenConfig.setProxy("foo", 8080);
+
+        KeenConfig.clearProxy();
+
+        assertNull(KeenConfig.getProxy());
+    }
+}

src/test/java/io/keen/client/java/KeenHttpRequestRunnableTest.java

@@ -0,0 +1,62 @@
+package io.keen.client.java;
+
+import org.junit.Test;
+
+import java.io.IOException;
+import java.net.*;
+
+import static org.junit.Assert.*;
+
+public class KeenHttpRequestRunnableTest {
+
+    private Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress("/", 8080));
+
+    @Test
+    public void willUseProxyIfConfigured() throws Exception {
+
+        KeenHttpRequestRunnable request = new KeenHttpRequestRunnable(null,null, null, null, proxy);
+
+        MockHandler handler = new MockHandler();
+
+        URL url = new URL("foo", "bar", 99, "/foobar", handler);
+
+        request.openConnection(url);
+
+        assertTrue(handler.calledWithProxy);
+        assertEquals(proxy, handler.openedProxy);
+    }
+
+    @Test
+    public void noProxyConfiguredWillNotUseAProxy() throws Exception {
+
+        KeenHttpRequestRunnable request = new KeenHttpRequestRunnable(null,null, null, null, null);
+
+        MockHandler handler = new MockHandler();
+
+        URL url = new URL("foo", "bar", 99, "/foobar", handler);
+
+        request.openConnection(url);
+
+        assertTrue(handler.calledWithoutProxy);
+        assertNull(handler.openedProxy);
+    }
+
+    class MockHandler extends URLStreamHandler {
+        boolean calledWithProxy;
+        boolean calledWithoutProxy;
+        Proxy openedProxy;
+
+        @Override
+        protected URLConnection openConnection(URL u) throws IOException {
+            calledWithoutProxy = true;
+            return null;
+        }
+
+        @Override
+        protected URLConnection openConnection(URL u, Proxy p) throws IOException {
+            calledWithProxy = true;
+            openedProxy = p;
+            return null;
+        }
+    };
+}