在建立之前阻止 websocket 连接

Question

我们的应用程序在嵌入式码头中使用 websockets。客户端传递一个包含 id 的 http header。我们要做的是在具有相同 ID 的客户端已经连接时阻止连接。不，我们在这里不是在谈论用户身份验证。

我们目前知道的唯一方法是在 @OnOpen-Endpoint 的回调中执行此检查。问题是这个方法只有在连接建立后才会被调用。所以第二个客户端的连接状态在切换。

相反，我们希望在建立连接之前执行检查。我们考虑过使用 ServletFilter，但根据另一个 question 的回答，它们不支持 websocket 通信。

服务器有没有办法阻止基于任意条件建立websocket连接？

Answer 1

所以正确的方法似乎是在自定义配置器中抛出 RuntimeException class。至少在码头示例中他们是这样做的：

https://github.com/eclipse/jetty.project/blob/master/jetty-websocket/javax-websocket-server-impl/src/test/java/examples/MyAuthedConfigurator.java

这仍然不是一个完美的解决方案，因为无法发送自定义 http 状态或 websocket 关闭代码。在客户端，这将导致通用堆栈跟踪：

java.io.IOException: Connect failure
    at org.eclipse.jetty.websocket.jsr356.ClientContainer.connect(ClientContainer.java:157)
    at org.eclipse.jetty.websocket.jsr356.ClientContainer.connectToServer(ClientContainer.java:180)
    at kam.cpush.ClientTestEndPoint.connect(ClientTestEndPoint.java:169)
    at kam.cpush.ClientTestEndPoint.connect(ClientTestEndPoint.java:155)
    at kam.cproxy.integrationtest.DuplicateControlChannelIT.connectToProxy(DuplicateControlChannelIT.java:72)
    at kam.cproxy.integrationtest.DuplicateControlChannelIT.testDuplicateChannelNotAllowed(DuplicateControlChannelIT.java:50)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:84)
    at org.testng.internal.Invoker.invokeMethod(Invoker.java:714)
    at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:901)
    at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1231)
    at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:127)
    at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:111)
    at org.testng.TestRunner.privateRun(TestRunner.java:767)
    at org.testng.TestRunner.run(TestRunner.java:617)
    at org.testng.SuiteRunner.runTest(SuiteRunner.java:334)
    at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:329)
    at org.testng.SuiteRunner.privateRun(SuiteRunner.java:291)
    at org.testng.SuiteRunner.run(SuiteRunner.java:240)
    at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
    at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
    at org.testng.TestNG.runSuitesSequentially(TestNG.java:1224)
    at org.testng.TestNG.runSuitesLocally(TestNG.java:1149)
    at org.testng.TestNG.run(TestNG.java:1057)
    at org.apache.maven.surefire.testng.TestNGExecutor.run(TestNGExecutor.java:115)
    at org.apache.maven.surefire.testng.TestNGDirectoryTestSuite.executeMulti(TestNGDirectoryTestSuite.java:205)
    at org.apache.maven.surefire.testng.TestNGDirectoryTestSuite.execute(TestNGDirectoryTestSuite.java:108)
    at org.apache.maven.surefire.testng.TestNGProvider.invoke(TestNGProvider.java:111)
    at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:203)
    at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:155)
    at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:103)
Caused by: org.eclipse.jetty.websocket.api.UpgradeException: Didn't switch protocols
    at org.eclipse.jetty.websocket.client.io.UpgradeConnection.validateResponse(UpgradeConnection.java:314)
    at org.eclipse.jetty.websocket.client.io.UpgradeConnection.read(UpgradeConnection.java:241)
    at org.eclipse.jetty.websocket.client.io.UpgradeConnection.onFillable(UpgradeConnection.java:163)
    at org.eclipse.jetty.io.AbstractConnection.run(AbstractConnection.java:544)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.run(QueuedThreadPool.java:555)
    at java.lang.Thread.run(Thread.java:745)

在建立之前阻止 websocket 连接

Prevent websocket connections before establishment

java

embedded-jetty

jetty-9

java-websocket