Added jsonp support to polling transport

Added integration tests for jsonp

engine.io-server-test/pom.xml

@@ -42,6 +42,18 @@
             <version>9.4.10.v20180503</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.seleniumhq.selenium</groupId>
+            <artifactId>selenium-server</artifactId>
+            <version>2.52.0</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.seleniumhq.selenium</groupId>
+            <artifactId>selenium-htmlunit-driver</artifactId>
+            <version>2.52.0</version>
+            <scope>test</scope>
+        </dependency>
 
         <dependency>
             <groupId>io.socket</groupId>

engine.io-server-test/src/test/java/io/socket/engineio/server/PollingJsonpTest.java

@@ -0,0 +1,121 @@
+package io.socket.engineio.server;
+
+import io.socket.engineio.parser.Packet;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.openqa.jetty.log.LogFactory;
+import org.openqa.selenium.WebDriver;
+import org.openqa.selenium.htmlunit.HtmlUnitDriver;
+import org.openqa.selenium.remote.server.SeleniumServer;
+import org.openqa.selenium.support.events.AbstractWebDriverEventListener;
+import org.openqa.selenium.support.events.EventFiringWebDriver;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.logging.Level;
+
+import static org.junit.Assert.*;
+
+public final class PollingJsonpTest {
+
+    private static SeleniumServer sSeleniumServer;
+
+    @Before
+    public void setup() {
+        LogFactory.getFactory().setAttribute("org.apache.commons.logging.Log", "org.apache.commons.logging.impl.NoOpLog");
+
+        java.util.logging.Logger.getLogger("com.gargoylesoftware.htmlunit").setLevel(Level.OFF);
+        java.util.logging.Logger.getLogger("org.apache.commons.httpclient").setLevel(Level.OFF);
+
+        sSeleniumServer = new SeleniumServer(4444);
+        sSeleniumServer.boot();
+    }
+
+    @After
+    public void teardown() {
+        sSeleniumServer.stop();
+    }
+
+    @Test
+    public void echoTest_string() throws Exception {
+        final ServerWrapper serverWrapper = new ServerWrapper();
+
+        try {
+            serverWrapper.startServer();
+            serverWrapper.getEngineIoServer().on("connection", args -> {
+                final EngineIoSocket socket = (EngineIoSocket) args[0];
+                socket.on("message", args1 -> {
+                    Packet packet = new Packet(Packet.MESSAGE);
+                    packet.data = args1[0];
+                    socket.send(packet);
+                });
+            });
+
+            assertEquals(0, executeScriptInBrowser(serverWrapper, "src/test/resources/testPollingJsonp_echo_string.js"));
+        } finally {
+            serverWrapper.stopServer();
+        }
+    }
+
+    @Test
+    public void reverseEchoTest() throws Exception {
+        final ServerWrapper serverWrapper = new ServerWrapper();
+        try {
+            serverWrapper.startServer();
+            serverWrapper.getEngineIoServer().on("connection", args -> {
+                final EngineIoSocket socket = (EngineIoSocket) args[0];
+                final String echoMessage = PollingTest.class.getSimpleName() + System.currentTimeMillis();
+                socket.on("message", args1 -> assertEquals(echoMessage, args1[0]));
+
+                Packet packet = new Packet(Packet.MESSAGE);
+                packet.data = echoMessage;
+                socket.send(packet);
+            });
+
+            assertEquals(0, executeScriptInBrowser(serverWrapper, "src/test/resources/testPollingJsonp_reverseEcho.js"));
+        } finally {
+            serverWrapper.stopServer();
+        }
+    }
+
+    @SuppressWarnings("ResultOfMethodCallIgnored")
+    private int executeScriptInBrowser(ServerWrapper serverWrapper, String script) throws IOException {
+        class ScriptResult {
+            int result = -1;
+        }
+
+        final HtmlUnitDriver webDriver = new HtmlUnitDriver(true);
+        final EventFiringWebDriver eventFiringWebDriver = new EventFiringWebDriver(webDriver);
+        final ScriptResult scriptResult = new ScriptResult();
+
+        try (FileInputStream fis = new FileInputStream(script)) {
+            final byte[] scriptBytes = new byte[fis.available()];
+            fis.read(scriptBytes);
+            final String scriptContent = new String(scriptBytes, StandardCharsets.UTF_8);
+
+            eventFiringWebDriver.get("http://127.0.0.1:" + serverWrapper.getPort() + "/testPollingJsonp.html");
+            eventFiringWebDriver.register(new AbstractWebDriverEventListener() {
+
+                @Override
+                public void afterScript(String script, WebDriver driver) {
+                    final String url = eventFiringWebDriver.getCurrentUrl();
+                    if (url.startsWith("http://www.example.com/?result=")) {
+                        scriptResult.result = Integer.parseInt(url.substring("http://www.example.com/?result=".length()));
+                    }
+                }
+            });
+            eventFiringWebDriver.executeScript(scriptContent, serverWrapper.getPort());
+
+            try {
+                Thread.sleep(3000);
+            } catch (InterruptedException ignore) {
+            }
+
+            return scriptResult.result;
+        } finally {
+            webDriver.close();
+        }
+    }
+}

engine.io-server-test/src/test/java/io/socket/engineio/server/ServerWrapper.java

@@ -1,5 +1,6 @@
 package io.socket.engineio.server;
 
+import org.apache.commons.io.IOUtils;
 import org.eclipse.jetty.http.pathmap.ServletPathSpec;
 import org.eclipse.jetty.server.Handler;
 import org.eclipse.jetty.server.Server;
@@ -14,7 +15,11 @@
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
+import java.io.File;
+import java.io.FileInputStream;
 import java.io.IOException;
+import java.io.PrintWriter;
+import java.nio.file.Files;
 import java.util.concurrent.atomic.AtomicInteger;
 
 final class ServerWrapper {
@@ -43,6 +48,26 @@ protected void service(HttpServletRequest request, HttpServletResponse response)
                 mEngineIoServer.handleRequest(request, response);
             }
         }), "/engine.io/*");
+        servletContextHandler.addServlet(new ServletHolder(new HttpServlet() {
+            @Override
+            protected void service(HttpServletRequest request, HttpServletResponse response) throws IOException {
+                final String path = request.getPathInfo();
+                final File file = new File("src/test/resources", path);
+                if (file.exists()) {
+                    response.setContentType(Files.probeContentType(file.toPath()));
+
+                    try (FileInputStream fis = new FileInputStream(file)) {
+                        IOUtils.copy(fis, response.getOutputStream());
+                    }
+                } else {
+                    response.setStatus(404);
+                    try (PrintWriter writer = response.getWriter()) {
+                        writer.print("Not Found");
+                        writer.flush();
+                    }
+                }
+            }
+        }), "/*");
 
         try {
             WebSocketUpgradeFilter webSocketUpgradeFilter = WebSocketUpgradeFilter.configureContext(servletContextHandler);

engine.io-server-test/src/test/resources/testPollingJsonp.html

@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+
+    <title>Polling Test - JSONP</title>
+
+    <script type="text/javascript" src="node_modules/engine.io-client/engine.io.js"></script>
+    <script type="text/javascript">
+        window.setResult = function (result) {
+            window.location = "http://www.example.com/?result=" + result;
+        };
+    </script>
+</head>
+<body>
+</body>
+</html>

engine.io-server-test/src/test/resources/testPollingJsonp_echo_string.js

@@ -0,0 +1,23 @@
+var returnError = function () {
+    window.setResult(1);
+};
+
+var port = arguments[0];
+socket = eio('http://127.0.0.1:' + port, {
+    transports: ['polling'],
+    jsonp: true,
+    forceJSONP: true
+});
+socket.on('open', function () {
+    var echoMessage = "Hello World";
+    socket.on('message', function (message) {
+        if(message === echoMessage) {
+            window.setResult(0);
+        } else {
+            returnError();
+        }
+    });
+    socket.send(echoMessage);
+});
+socket.on('error', returnError);
+setTimeout(returnError, 750);

engine.io-server-test/src/test/resources/testPollingJsonp_reverseEcho.js

@@ -0,0 +1,19 @@
+var returnError = function () {
+    window.setResult(1);
+};
+
+var port = arguments[0];
+socket = eio('http://127.0.0.1:' + port, {
+    transports: ['polling'],
+    jsonp: true,
+    forceJSONP: true
+});
+socket.on("message", function (message) {
+    socket.sendPacket("message", message);
+
+    setTimeout(function () {
+        window.setResult(0);
+    }, 100);
+});
+socket.on('error', returnError);
+setTimeout(returnError, 750);

engine.io-server/src/main/java/io/socket/engineio/server/transport/Polling.java

@@ -3,6 +3,9 @@
 import io.socket.engineio.parser.Packet;
 import io.socket.engineio.parser.ServerParser;
 import io.socket.engineio.server.Transport;
+import io.socket.parseqs.ParseQS;
+import org.json.JSONArray;
+import org.json.JSONObject;
 
 import javax.servlet.ServletInputStream;
 import javax.servlet.http.HttpServletRequest;
@@ -69,23 +72,41 @@ public synchronized void send(List<Packet> packets) {
             packets.add(new Packet(Packet.CLOSE));
         }
 
-        @SuppressWarnings("unchecked")
-        final boolean supportsBinary = (!((Map<String, String>) mRequest.getAttribute("query")).containsKey("b64"));
+        //noinspection unchecked
+        final Map<String, String> query = (Map<String, String>) mRequest.getAttribute("query");
+
+        final boolean supportsBinary = !query.containsKey("b64");
+        final boolean jsonp = query.containsKey("j");
 
         if(packets.size() == 0) {
             throw new IllegalArgumentException("No packets to send.");
         }
         ServerParser.encodePayload(packets.toArray(new Packet[0]), supportsBinary, data -> {
-            final String contentType = (data instanceof String)? "text/plain; charset=UTF-8" : "application/octet-stream";
-            final int contentLength = (data instanceof String)? ((String) data).length() : ((byte[]) data).length;
+            final String contentType;
+            final byte[] contentBytes;
+
+            if (jsonp) {
+                final String jsonpIndex = query.get("j").replaceAll("[^0-9]", "");
+                final String jsonContentString = (data instanceof String)?
+                        JSONObject.quote((String)data) :
+                        JSONObject.valueToString(new JSONArray(data));
+                final String jsContentString = jsonContentString
+                        .replace("\u2028", "\\u2028")
+                        .replace("\u2029", "\\u2029");
+                final String contentString = "___eio[" + jsonpIndex + "](" + jsContentString + ")";
+
+                contentType = "text/javascript; charset=UTF-8";
+                contentBytes = contentString.getBytes(StandardCharsets.UTF_8);
+            } else {
+                contentType = (data instanceof String)? "text/plain; charset=UTF-8" : "application/octet-stream";
+                contentBytes = (data instanceof String)? ((String)data).getBytes(StandardCharsets.UTF_8) : ((byte[])data);
+            }
 
             mResponse.setContentType(contentType);
-            mResponse.setContentLength(contentLength);
+            mResponse.setContentLength(contentBytes.length);
 
             try (OutputStream outputStream = mResponse.getOutputStream()) {
-                // TODO: Support JSONP
-                byte[] writeBytes = (data instanceof String)? ((String) data).getBytes(StandardCharsets.UTF_8) : ((byte[]) data);
-                outputStream.write(writeBytes);
+                outputStream.write(contentBytes);
             } catch (IOException ex) {
                 onError("write failure", ex.getMessage());
             }
@@ -148,15 +169,25 @@ private void onPollRequest(@SuppressWarnings("unused") HttpServletRequest reques
     }
 
     private void onDataRequest(final HttpServletRequest request, final HttpServletResponse response) throws IOException {
+        //noinspection unchecked
+        final Map<String, String> query = (Map<String, String>) mRequest.getAttribute("query");
+
         final boolean isBinary = request.getContentType().equals("application/octet-stream");
+        final boolean jsonp = query.containsKey("j");
 
         try(final ServletInputStream inputStream = request.getInputStream()) {
             final byte[] mReadBuffer = new byte[request.getContentLength()];
 
             //noinspection ResultOfMethodCallIgnored
             inputStream.read(mReadBuffer, 0, mReadBuffer.length);
 
-            onData((isBinary)? mReadBuffer : (new String(mReadBuffer, StandardCharsets.UTF_8)));
+            if (jsonp) {
+                final String packetPayloadRaw = ParseQS.decode(new String(mReadBuffer, StandardCharsets.UTF_8)).get("d");
+                final String packetPayload = packetPayloadRaw.replace("\\n", "\n");
+                onData(packetPayload);
+            } else {
+                onData((isBinary)? mReadBuffer : (new String(mReadBuffer, StandardCharsets.UTF_8)));
+            }
         }
 
         response.setContentType("text/html");