Add gzip to outgoing requests. According to my benchmarks it has a very small effect.

api/src/com/todoroo/andlib/service/HttpRestClient.java

@@ -5,10 +5,16 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.lang.ref.WeakReference;
+import java.util.zip.GZIPInputStream;
 
 import org.apache.http.Header;
+import org.apache.http.HeaderElement;
 import org.apache.http.HttpEntity;
+import org.apache.http.HttpException;
+import org.apache.http.HttpRequest;
+import org.apache.http.HttpRequestInterceptor;
 import org.apache.http.HttpResponse;
+import org.apache.http.HttpResponseInterceptor;
 import org.apache.http.HttpVersion;
 import org.apache.http.client.HttpClient;
 import org.apache.http.client.methods.HttpGet;
@@ -19,12 +25,14 @@ import org.apache.http.conn.scheme.PlainSocketFactory;
 import org.apache.http.conn.scheme.Scheme;
 import org.apache.http.conn.scheme.SchemeRegistry;
 import org.apache.http.conn.ssl.SSLSocketFactory;
+import org.apache.http.entity.HttpEntityWrapper;
 import org.apache.http.impl.client.DefaultHttpClient;
 import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
 import org.apache.http.params.BasicHttpParams;
 import org.apache.http.params.HttpConnectionParams;
 import org.apache.http.params.HttpParams;
 import org.apache.http.params.HttpProtocolParams;
+import org.apache.http.protocol.HttpContext;
 
 import android.util.Log;
 
@@ -49,15 +57,36 @@ public class HttpRestClient implements RestClient {
     private WeakReference<HttpClient> httpClient = null;
 
     protected boolean debug = false;
+
     private int timeout = TIMEOUT_MILLIS;
 
+    @SuppressWarnings("nls")
     public HttpRestClient() {
         DependencyInjectionService.getInstance().inject(this);
+
+        System.err.println("NEW REST CLIENT");
+
+        SchemeRegistry schemeRegistry = new SchemeRegistry();
+        schemeRegistry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
+        schemeRegistry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
+
+        params = new BasicHttpParams();
+        HttpConnectionParams.setConnectionTimeout(params, timeout);
+        HttpConnectionParams.setSoTimeout(params, timeout);
+        params.setParameter(ConnManagerPNames.MAX_TOTAL_CONNECTIONS, 30);
+        params.setParameter(ConnManagerPNames.MAX_CONNECTIONS_PER_ROUTE, new ConnPerRouteBean(30));
+        params.setParameter(HttpProtocolParams.USE_EXPECT_CONTINUE, false);
+        HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
+
+        cm = new ThreadSafeClientConnManager(params, schemeRegistry);
     }
 
     public HttpRestClient(int timeout) {
         super();
         this.timeout = timeout;
+
+        HttpConnectionParams.setConnectionTimeout(params, timeout);
+        HttpConnectionParams.setSoTimeout(params, timeout);
     }
 
     private static String convertStreamToString(InputStream is) {
@@ -88,28 +117,74 @@ public class HttpRestClient implements RestClient {
         return sb.toString();
     }
 
+    private HttpParams params;
+    private ThreadSafeClientConnManager cm;
+
     @SuppressWarnings("nls")
     private synchronized HttpClient getClient() {
         if (httpClient == null || httpClient.get() == null) {
-            SchemeRegistry schemeRegistry = new SchemeRegistry();
-            schemeRegistry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
-            schemeRegistry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
-
-            HttpParams params = new BasicHttpParams();
-            HttpConnectionParams.setConnectionTimeout(params, timeout);
-            HttpConnectionParams.setSoTimeout(params, timeout);
-            params.setParameter(ConnManagerPNames.MAX_TOTAL_CONNECTIONS, 30);
-            params.setParameter(ConnManagerPNames.MAX_CONNECTIONS_PER_ROUTE, new ConnPerRouteBean(30));
-            params.setParameter(HttpProtocolParams.USE_EXPECT_CONTINUE, false);
-            HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
-
-            ThreadSafeClientConnManager cm = new ThreadSafeClientConnManager(params, schemeRegistry);
-            HttpClient client = new DefaultHttpClient(cm, params);
+            DefaultHttpClient client = new DefaultHttpClient(cm, params);
             httpClient = new WeakReference<HttpClient>(client);
+            actsAsGzippable(client);
             return client;
-        } else {
-            return httpClient.get();
         }
+        return httpClient.get();
+    }
+
+    @SuppressWarnings("nls")
+    protected void actsAsGzippable(DefaultHttpClient client) {
+        client.addRequestInterceptor(new HttpRequestInterceptor() {
+            public void process(
+                    final HttpRequest request,
+                    final HttpContext context) throws HttpException, IOException {
+                if (!request.containsHeader("Accept-Encoding"))
+                        request.addHeader("Accept-Encoding", "gzip");
+            }
+
+        });
+
+        client.addResponseInterceptor(new HttpResponseInterceptor() {
+            public void process(
+                    final HttpResponse response,
+                    final HttpContext context) throws HttpException, IOException {
+                HttpEntity entity = response.getEntity();
+                Header ceheader = entity.getContentEncoding();
+                if (ceheader != null) {
+                    HeaderElement[] codecs = ceheader.getElements();
+                    for (int i = 0; i < codecs.length; i++) {
+                        if (codecs[i].getName().equalsIgnoreCase("gzip")) {
+                            response.setEntity(
+                                    new GzipDecompressingEntity(response.getEntity()));
+                            return;
+                        }
+                    }
+                }
+            }
+        });
+    }
+
+    private static class GzipDecompressingEntity extends HttpEntityWrapper {
+
+        public GzipDecompressingEntity(final HttpEntity entity) {
+            super(entity);
+        }
+
+        @Override
+        public InputStream getContent()
+            throws IOException, IllegalStateException {
+
+            // the wrapped entity's getContent() decides about repeatability
+            InputStream wrappedin = wrappedEntity.getContent();
+
+            return new GZIPInputStream(wrappedin);
+        }
+
+        @Override
+        public long getContentLength() {
+            // length of ungzipped content is not known
+            return -1;
+        }
+
     }
 
     private String processHttpResponse(HttpResponse response) throws IOException {