proxy support

src/main/java/io/socket/engineio/client/HttpConnectionProvider.java

@@ -0,0 +1,12 @@
+package io.socket.engineio.client;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+/**
+ * @author Eugene.Kudelevsky
+ */
+public interface HttpConnectionProvider {
+    HttpURLConnection openConnection(URL url) throws IOException;
+}

src/main/java/io/socket/engineio/client/Socket.java

@@ -128,6 +128,11 @@ public class Socket extends Emitter {
     private Future pingIntervalTimer;
     private SSLContext sslContext;
     private HostnameVerifier hostnameVerifier;
+    public String proxyHost;
+    public int proxyPort = -1;
+    public String proxyLogin;
+    public String proxyPassword;
+    private HttpConnectionProvider httpConnectionProvider;
 
     private ReadyState readyState;
     private ScheduledExecutorService heartbeatScheduler;
@@ -205,6 +210,11 @@ public class Socket extends Emitter {
         this.policyPort = opts.policyPort != 0 ? opts.policyPort : 843;
         this.rememberUpgrade = opts.rememberUpgrade;
         this.hostnameVerifier = opts.hostnameVerifier != null ? opts.hostnameVerifier : defaultHostnameVerifier;
+        this.proxyHost = opts.proxyHost;
+        this.proxyPort = opts.proxyPort;
+        this.proxyLogin = opts.proxyLogin;
+        this.proxyPassword = opts.proxyPassword;
+        this.httpConnectionProvider = opts.httpConnectionProvider;
     }
 
     public static void setDefaultSSLContext(SSLContext sslContext) {
@@ -271,6 +281,11 @@ public class Socket extends Emitter {
         opts.policyPort = this.policyPort;
         opts.socket = this;
         opts.hostnameVerifier = this.hostnameVerifier;
+        opts.proxyHost = this.proxyHost;
+        opts.proxyPort = this.proxyPort;
+        opts.proxyLogin = this.proxyLogin;
+        opts.proxyPassword = this.proxyPassword;
+        opts.httpConnectionProvider = this.httpConnectionProvider;
 
         Transport transport;
         if (WebSocket.NAME.equals(name)) {

src/main/java/io/socket/engineio/client/Transport.java

@@ -43,6 +43,11 @@ public abstract class Transport extends Emitter {
     protected SSLContext sslContext;
     protected Socket socket;
     protected HostnameVerifier hostnameVerifier;
+    protected String proxyHost;
+    protected int proxyPort;
+    protected String proxyLogin;
+    protected String proxyPassword;
+    protected HttpConnectionProvider httpConnectionProvider;
 
     protected ReadyState readyState;
 
@@ -57,6 +62,11 @@ public abstract class Transport extends Emitter {
         this.sslContext = opts.sslContext;
         this.socket = opts.socket;
         this.hostnameVerifier = opts.hostnameVerifier;
+        this.proxyHost = opts.proxyHost;
+        this.proxyPort = opts.proxyPort;
+        this.proxyLogin = opts.proxyLogin;
+        this.proxyPassword = opts.proxyPassword;
+        this.httpConnectionProvider = opts.httpConnectionProvider;
     }
 
     protected Transport onError(String msg, Exception desc) {
@@ -152,5 +162,10 @@ public abstract class Transport extends Emitter {
         public SSLContext sslContext;
         public HostnameVerifier hostnameVerifier;
         protected Socket socket;
+        public String proxyHost;
+        public int proxyPort = -1;
+        public String proxyLogin;
+        public String proxyPassword;
+        public HttpConnectionProvider httpConnectionProvider;
     }
 }

src/main/java/io/socket/engineio/client/transports/PollingXHR.java

@@ -2,8 +2,9 @@ package io.socket.engineio.client.transports;
 
 
 import io.socket.emitter.Emitter;
-import io.socket.thread.EventThread;
+import io.socket.engineio.client.HttpConnectionProvider;
 import io.socket.engineio.client.Transport;
+import io.socket.thread.EventThread;
 
 import javax.net.ssl.HostnameVerifier;
 import javax.net.ssl.HttpsURLConnection;
@@ -37,6 +38,7 @@ public class PollingXHR extends Polling {
         opts.uri = this.uri();
         opts.sslContext = this.sslContext;
         opts.hostnameVerifier = this.hostnameVerifier;
+        opts.httpConnectionProvider = this.httpConnectionProvider;
 
         Request req = new Request(opts);
 
@@ -149,6 +151,7 @@ public class PollingXHR extends Polling {
         private SSLContext sslContext;
         private HttpURLConnection xhr;
         private HostnameVerifier hostnameVerifier;
+        private HttpConnectionProvider httpConnectionProvider;
 
         public Request(Options opts) {
             this.method = opts.method != null ? opts.method : "GET";
@@ -156,6 +159,7 @@ public class PollingXHR extends Polling {
             this.data = opts.data;
             this.sslContext = opts.sslContext;
             this.hostnameVerifier = opts.hostnameVerifier;
+            this.httpConnectionProvider = opts.httpConnectionProvider;
         }
 
         public void create() {
@@ -163,7 +167,12 @@ public class PollingXHR extends Polling {
             try {
                 logger.fine(String.format("xhr open %s: %s", this.method, this.uri));
                 URL url = new URL(this.uri);
-                xhr = (HttpURLConnection)url.openConnection();
+                if (httpConnectionProvider != null) {
+                    xhr = httpConnectionProvider.openConnection(url);
+                }
+                if (xhr == null) {
+                    xhr = (HttpURLConnection) url.openConnection();
+                }
                 xhr.setRequestMethod(this.method);
             } catch (IOException e) {
                 this.onError(e);
@@ -322,6 +331,7 @@ public class PollingXHR extends Polling {
             public byte[] data;
             public SSLContext sslContext;
             public HostnameVerifier hostnameVerifier;
+            public HttpConnectionProvider httpConnectionProvider;
         }
     }
 }

src/main/java/io/socket/engineio/client/transports/WebSocket.java

@@ -8,17 +8,15 @@ import io.socket.parseqs.ParseQS;
 import io.socket.thread.EventThread;
 import io.socket.utf8.UTF8Exception;
 import io.socket.yeast.Yeast;
-import okhttp3.OkHttpClient;
-import okhttp3.Request;
-import okhttp3.RequestBody;
-import okhttp3.Response;
-import okhttp3.ResponseBody;
+import okhttp3.*;
 import okhttp3.ws.WebSocketCall;
 import okhttp3.ws.WebSocketListener;
 import okio.Buffer;
 
 import javax.net.ssl.SSLSocketFactory;
 import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.Proxy;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -61,6 +59,21 @@ public class WebSocket extends Transport {
         if (this.hostnameVerifier != null) {
             clientBuilder.hostnameVerifier(this.hostnameVerifier);
         }
+        if (proxyHost != null && !proxyHost.isEmpty() && proxyPort >= 0) {
+            clientBuilder.proxy(new Proxy(Proxy.Type.HTTP, new InetSocketAddress(proxyHost, proxyPort)));
+        }
+        if (proxyLogin != null && !proxyLogin.isEmpty()) {
+            final String credentials = Credentials.basic(proxyLogin, proxyPassword);
+
+            clientBuilder.proxyAuthenticator(new Authenticator() {
+                @Override
+                public Request authenticate(Route route, Response response) throws IOException {
+                    return response.request().newBuilder()
+                            .header("Proxy-Authorization", credentials)
+                            .build();
+                }
+            });
+        }
         Request.Builder builder = new Request.Builder().url(uri());
         for (Map.Entry<String, List<String>> entry : headers.entrySet()) {
             for (String v : entry.getValue()) {