Sporadic HttpConfiguratonTest failures on Jenkins and Travis

## Expected Behavior

The tests for the new HTTP configuration should work.

## Current Behavior

From time to time we are seeing errors when running the `HttpConfigurationTest` class in CI environments. I saw the same issue on Jenkins and Travis so it doesn't seem to be related to a specific CI environment.

Example Travis job: https://travis-ci.org/Graylog2/graylog2-server/builds/325398290

Excerpt:

```
HttpConfigurationTest.testHttpBindAddressIsIPv6AddressWithoutBrackets
Expected: (an instance of com.github.joschi.jadconfig.ValidationException and exception with message a string containing "Possible bracketless IPv6 literal: 2001:db8::1")
but: exception with message a string containing "Possible bracketless IPv6 literal: 2001:db8::1" message was "Couldn't run validator method"
Stacktrace was: com.github.joschi.jadconfig.ValidationException: Couldn't run validator method
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:227)
at com.github.joschi.jadconfig.JadConfig.process(JadConfig.java:100)
at org.graylog2.configuration.HttpConfigurationTest.testHttpBindAddressIsIPv6AddressWithoutBrackets(HttpConfigurationTest.java:70)
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.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.rules.ExpectedException$ExpectedExceptionStatement.evaluate(ExpectedException.java:239)
at org.junit.rules.ExternalResource$1.evaluate(ExternalResource.java:48)
at org.junit.rules.RunRules.evaluate(RunRules.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
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.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:367)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeWithRerun(JUnit4Provider.java:274)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:238)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:161)
at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:290)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:242)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:121)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.github.joschi.jadconfig.ReflectionUtils.invokeMethodsWithAnnotation(ReflectionUtils.java:53)
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:221)
... 30 more
Caused by: java.lang.IllegalArgumentException: Possible bracketless IPv6 literal: 2001:db8::1
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:210)
at com.google.common.net.HostAndPort.requireBracketsForIPv6(HostAndPort.java:276)
at org.graylog2.configuration.HttpConfiguration.getHttpBindAddress(HttpConfiguration.java:88)
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:129)
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:125)
at org.graylog2.configuration.HttpConfiguration.getHttpPublishUri(HttpConfiguration.java:108)
at org.graylog2.configuration.HttpConfiguration.getHttpExternalUri(HttpConfiguration.java:215)
at org.graylog2.configuration.HttpConfiguration.validateHttpExternalUriPathEndsWithSlash(HttpConfiguration.java:242)
... 35 more
```

Full errors:

```
Results :

Failed tests:
HttpConfigurationTest.testHttpBindAddressIsIPv6AddressWithoutBrackets
Expected: (an instance of com.github.joschi.jadconfig.ValidationException and exception with message a string containing "Possible bracketless IPv6 literal: 2001:db8::1")
but: exception with message a string containing "Possible bracketless IPv6 literal: 2001:db8::1" message was "Couldn't run validator method"
Stacktrace was: com.github.joschi.jadconfig.ValidationException: Couldn't run validator method
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:227)
at com.github.joschi.jadconfig.JadConfig.process(JadConfig.java:100)
at org.graylog2.configuration.HttpConfigurationTest.testHttpBindAddressIsIPv6AddressWithoutBrackets(HttpConfigurationTest.java:70)
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.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.rules.ExpectedException$ExpectedExceptionStatement.evaluate(ExpectedException.java:239)
at org.junit.rules.ExternalResource$1.evaluate(ExternalResource.java:48)
at org.junit.rules.RunRules.evaluate(RunRules.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
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.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:367)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeWithRerun(JUnit4Provider.java:274)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:238)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:161)
at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:290)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:242)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:121)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.github.joschi.jadconfig.ReflectionUtils.invokeMethodsWithAnnotation(ReflectionUtils.java:53)
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:221)
... 30 more
Caused by: java.lang.IllegalArgumentException: Possible bracketless IPv6 literal: 2001:db8::1
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:210)
at com.google.common.net.HostAndPort.requireBracketsForIPv6(HostAndPort.java:276)
at org.graylog2.configuration.HttpConfiguration.getHttpBindAddress(HttpConfiguration.java:88)
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:129)
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:125)
at org.graylog2.configuration.HttpConfiguration.getHttpPublishUri(HttpConfiguration.java:108)
at org.graylog2.configuration.HttpConfiguration.getHttpExternalUri(HttpConfiguration.java:215)
at org.graylog2.configuration.HttpConfiguration.validateHttpExternalUriPathEndsWithSlash(HttpConfiguration.java:242)
... 35 more

HttpConfigurationTest.testHttpBindAddressIsInvalidHostName
Expected: (an instance of com.github.joschi.jadconfig.ValidationException and exception with message a string containing "this-does-not-exist-42: ")
but: exception with message a string containing "this-does-not-exist-42: " message was "java.net.UnknownHostException: this-does-not-exist-42"
Stacktrace was: com.github.joschi.jadconfig.ValidationException: java.net.UnknownHostException: this-does-not-exist-42
at org.graylog2.configuration.HttpConfiguration.validateHttpBindAddress(HttpConfiguration.java:227)
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 com.github.joschi.jadconfig.ReflectionUtils.invokeMethodsWithAnnotation(ReflectionUtils.java:53)
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:221)
at com.github.joschi.jadconfig.JadConfig.process(JadConfig.java:100)
at org.graylog2.configuration.HttpConfigurationTest.testHttpBindAddressIsInvalidHostName(HttpConfigurationTest.java:109)
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.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.rules.ExpectedException$ExpectedExceptionStatement.evaluate(ExpectedException.java:239)
at org.junit.rules.ExternalResource$1.evaluate(ExternalResource.java:48)
at org.junit.rules.RunRules.evaluate(RunRules.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
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.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:367)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeWithRerun(JUnit4Provider.java:274)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:238)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:161)
at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:290)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:242)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:121)
Caused by: java.net.UnknownHostException: this-does-not-exist-42
at java.net.InetAddress.getAllByName0(InetAddress.java:1280)
at java.net.InetAddress.getAllByName(InetAddress.java:1192)
at java.net.InetAddress.getAllByName(InetAddress.java:1126)
at java.net.InetAddress.getByName(InetAddress.java:1076)
at org.graylog2.configuration.HttpConfiguration.validateHttpBindAddress(HttpConfiguration.java:224)
... 36 more

HttpConfigurationTest.testHttpBindAddressIsInvalidIPv4Address
Expected: (an instance of com.github.joschi.jadconfig.ValidationException and exception with message a string containing "1234.5.6.7: ")
but: exception with message a string containing "1234.5.6.7: " message was "Couldn't run validator method"
Stacktrace was: com.github.joschi.jadconfig.ValidationException: Couldn't run validator method
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:227)
at com.github.joschi.jadconfig.JadConfig.process(JadConfig.java:100)
at org.graylog2.configuration.HttpConfigurationTest.testHttpBindAddressIsInvalidIPv4Address(HttpConfigurationTest.java:99)
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.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.rules.ExpectedException$ExpectedExceptionStatement.evaluate(ExpectedException.java:239)
at org.junit.rules.ExternalResource$1.evaluate(ExternalResource.java:48)
at org.junit.rules.RunRules.evaluate(RunRules.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
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$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:367)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeWithRerun(JUnit4Provider.java:274)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:238)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:161)
at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:290)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:242)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:121)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.github.joschi.jadconfig.ReflectionUtils.invokeMethodsWithAnnotation(ReflectionUtils.java:53)
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:221)
... 30 more
Caused by: java.lang.RuntimeException: Invalid http_publish_uri.
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:171)
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:125)
at org.graylog2.configuration.HttpConfiguration.getHttpPublishUri(HttpConfiguration.java:108)
at org.graylog2.configuration.HttpConfiguration.getHttpExternalUri(HttpConfiguration.java:215)
at org.graylog2.configuration.HttpConfiguration.validateHttpExternalUriPathEndsWithSlash(HttpConfiguration.java:242)
... 36 more
Caused by: java.net.URISyntaxException: Illegal character in hostname at index 16: http://1234.5.6.7:9000/
at java.net.URI$Parser.fail(URI.java:2848)
at java.net.URI$Parser.parseHostname(URI.java:3395)
at java.net.URI$Parser.parseServer(URI.java:3236)
at java.net.URI$Parser.parseAuthority(URI.java:3155)
at java.net.URI$Parser.parseHierarchical(URI.java:3097)
at java.net.URI$Parser.parse(URI.java:3053)
at java.net.URI.(URI.java:673)
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:165)
... 40 more

HttpConfigurationTest.testHttpBindAddressIsInvalidIPv6Address
Expected: (an instance of com.github.joschi.jadconfig.ValidationException and exception with message a string containing "Possible bracketless IPv6 literal: ff$$::1")
but: exception with message a string containing "Possible bracketless IPv6 literal: ff$$::1" message was "Couldn't run validator method"
Stacktrace was: com.github.joschi.jadconfig.ValidationException: Couldn't run validator method
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:227)
at com.github.joschi.jadconfig.JadConfig.process(JadConfig.java:100)
at org.graylog2.configuration.HttpConfigurationTest.testHttpBindAddressIsInvalidIPv6Address(HttpConfigurationTest.java:80)
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.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.rules.ExpectedException$ExpectedExceptionStatement.evaluate(ExpectedException.java:239)
at org.junit.rules.ExternalResource$1.evaluate(ExternalResource.java:48)
at org.junit.rules.RunRules.evaluate(RunRules.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
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.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:367)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeWithRerun(JUnit4Provider.java:274)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:238)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:161)
at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:290)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:242)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:121)
Caused by: java.lang.reflect.InvocationTargetException
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 com.github.joschi.jadconfig.ReflectionUtils.invokeMethodsWithAnnotation(ReflectionUtils.java:53)
at com.github.joschi.jadconfig.JadConfig.invokeValidatorMethods(JadConfig.java:221)
... 30 more
Caused by: java.lang.IllegalArgumentException: Possible bracketless IPv6 literal: ff$$::1
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:210)
at com.google.common.net.HostAndPort.requireBracketsForIPv6(HostAndPort.java:276)
at org.graylog2.configuration.HttpConfiguration.getHttpBindAddress(HttpConfiguration.java:88)
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:129)
at org.graylog2.configuration.HttpConfiguration.getDefaultHttpUri(HttpConfiguration.java:125)
at org.graylog2.configuration.HttpConfiguration.getHttpPublishUri(HttpConfiguration.java:108)
at org.graylog2.configuration.HttpConfiguration.getHttpExternalUri(HttpConfiguration.java:215)
at org.graylog2.configuration.HttpConfiguration.validateHttpExternalUriPathEndsWithSlash(HttpConfiguration.java:242)
... 36 more
```

## Steps to Reproduce (for bugs)

I was unable to reproduce it.

## Context

Since I am unable to reproduce it locally, I was thinking if this might be a concurrency issue when maven is running the tests in parallel.

## Your Environment

* Graylog Version: 3.0.0-SNAPSHOT