Unnable to start container - checkExposedPort - NullPointerException

[VladoDemcak]

Hi,

this is not very common issue (sometime happens, but not very often). Testcontainers java client is failing due NullPointerException while container initialization in checkExposedPort method. See error below:

java.lang.ExceptionInInitializerError
	at sun.misc.Unsafe.ensureClassInitialized(Native Method)
	at sun.reflect.UnsafeFieldAccessorFactory.newFieldAccessor(UnsafeFieldAccessorFactory.java:43)
	at sun.reflect.ReflectionFactory.newFieldAccessor(ReflectionFactory.java:142)
	at java.lang.reflect.Field.acquireFieldAccessor(Field.java:1088)
	at java.lang.reflect.Field.getFieldAccessor(Field.java:1069)
	at java.lang.reflect.Field.get(Field.java:393)
	at org.junit.runners.model.FrameworkField.get(FrameworkField.java:73)
	at org.junit.runners.model.TestClass.getAnnotatedFieldValues(TestClass.java:230)
	at org.junit.runners.ParentRunner.classRules(ParentRunner.java:255)
	at org.junit.runners.ParentRunner.withClassRules(ParentRunner.java:244)
	at org.junit.runners.ParentRunner.classBlock(ParentRunner.java:194)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:362)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
	at org.junit.runners.Suite.runChild(Suite.java:128)
	at org.junit.runners.Suite.runChild(Suite.java:27)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: java.lang.NullPointerException
	at org.testcontainers.DockerClientFactory.checkExposedPort(DockerClientFactory.java:186)
	at org.testcontainers.DockerClientFactory.lambda$client$1(DockerClientFactory.java:129)
	at org.testcontainers.DockerClientFactory.runInsideDocker(DockerClientFactory.java:230)
	at org.testcontainers.DockerClientFactory.client(DockerClientFactory.java:118)
	at org.testcontainers.containers.GenericContainer.<init>(GenericContainer.java:116)
	at org.testcontainers.containers.FixedHostPortGenericContainer.<init>(FixedHostPortGenericContainer.java:16)
	at Test.<clinit>(Test.java:62)
	... 26 more

[kiview]

Hi @VladoDemcak, can you please share a bit more of your code? Do you use @Rule or @ClassRule?

[rnorth]

I think this might be happening during the 'pre-flight checks' (where it's checking if the Docker environment looks healthy, after the disk space and mountable file checks). Can you confirm that @VladoDemcak ?

Also it'd be useful to know which version of Testcontainers we're using so that we can line up the line numbers in the stack trace!
Thanks

[VladoDemcak]

@kiview

@ClassRule
    public static GenericContainer arangodbContainer = new FixedHostPortGenericContainer("arangodb:3.2.0")
            .withFixedExposedPort(arangoPort, 8529)
            .withEnv("ARANGO_NO_AUTH", "1")
            .waitingFor(
                    Wait.forHttp("/_db/_system/")
                        .forStatusCode(200));

@rnorth
we are using 1.4.2 version. Probably it's happening in the checks of environment but I am not sure. Anyway I think there should be some check for NullPointer. I was not able to spot what was NullPointer (as I said it's happening unpredictable). But I guess it's this line:

inspectedContainer.getNetworkSettings().getPorts().getBindings().values().iterator().next()[0].getHostPortSpec();