WireMock in Junit in Jenkins - BindException: Address already in use

Question

I have some Junit test in which I use WireMock. Locally the tests pass, but on Jenkins I get an error of java.lang.RuntimeException: java.net.BindException: Address already in use

In the WireMock configuration I set dynamicHttpsPort() (which according to docs "Randomly asssign the HTTPS port on startup") and its working locally, but on Jenkins it fails.

My WireMock configuration is

    @Rule
    public WireMockRule wireMockRule = new WireMockRule(wireMockConfig()
            .dynamicHttpsPort()
            .keystorePath(certsDir.resolve("server.jks").toString())
            .keystorePassword(MY_PASS)
            .keystoreType("JKS")
    );

I have 2 JUnit classes in which I create a new WireMockRule, and they may run simultaneously. In one of the classes I have 4 tests and in the other one I have one test. All 5 tests fail.

And the full stack trace is:

com.github.tomakehurst.wiremock.common.FatalStartupException: java.lang.RuntimeException: java.net.BindException: Address already in use
    at com.github.tomakehurst.wiremock.WireMockServer.start(WireMockServer.java:146)
    at com.github.tomakehurst.wiremock.junit.WireMockRule$1.evaluate(WireMockRule.java:68)
    at org.junit.rules.RunRules.evaluate(RunRules.java:20)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.apache.maven.surefire.junit4.JUnit4TestSet.execute(JUnit4TestSet.java:53)
    at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:123)
    at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:104)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray(ReflectionUtils.java:164)
    at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:110)
    at org.apache.maven.surefire.booter.SurefireStarter.invokeProvider(SurefireStarter.java:172)
    at org.apache.maven.surefire.booter.SurefireStarter.runSuitesInProcessWhenForked(SurefireStarter.java:104)
    at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:70)
Caused by: java.lang.RuntimeException: java.net.BindException: Address already in use
    at com.github.tomakehurst.wiremock.jetty9.JettyHttpServer.start(JettyHttpServer.java:139)
    at com.github.tomakehurst.wiremock.WireMockServer.start(WireMockServer.java:144)
    ... 23 more
Caused by: java.net.BindException: Address already in use
    at sun.nio.ch.Net.bind0(Native Method)
    at sun.nio.ch.Net.bind(Net.java:433)
    at sun.nio.ch.Net.bind(Net.java:425)
    at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:223)
    at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74)
    at wiremock.org.eclipse.jetty.server.ServerConnector.open(ServerConnector.java:321)
    at wiremock.org.eclipse.jetty.server.AbstractNetworkConnector.doStart(AbstractNetworkConnector.java:80)
    at wiremock.org.eclipse.jetty.server.ServerConnector.doStart(ServerConnector.java:236)
    at wiremock.org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at wiremock.org.eclipse.jetty.server.Server.doStart(Server.java:366)
    at wiremock.org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at com.github.tomakehurst.wiremock.jetty9.JettyHttpServer.start(JettyHttpServer.java:137)
    ... 24 more

Solution

Found the solution here:

The problem is that you're not setting the HTTP port on either, which will always be active and default to 8080 (hence them clashing). If you add dynamicPort() to both configs it should fix it.

So adding dynamicPort() fixed it:

    @Rule
    public WireMockRule wireMockRule = new WireMockRule(wireMockConfig()
            .dynamicPort()
            .dynamicHttpsPort()
            .keystorePath(certsDir.resolve("server.jks").toString())
            .keystorePassword(MY_PASS)
            .keystoreType("JKS")
    );