NPE in docker:build if neither certPath nor $DOCKER_CERT_PATH are defined

[rkondrashov]

Description

When neither certPath property set nor DOCKER_CERT_PATH environment variable is defined, docker:build task fails with NPE. An error message at this point would be better.

Info

• d-m-p version : 0.20.1
• Maven version: 3.3.9
• Docker version : 17.03.0-ce
• OS: linux/amd64

[ERROR] Failed to execute goal io.fabric8:docker-maven-plugin:0.20.1:build (default-cli) on project test-service: Execution default-cli of goal io.fabric8:docker-maven-plugin:0.20.1:build failed. NullPointerException -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal io.fabric8:docker-maven-plugin:0.20.1:build (default-cli) on project test-service: Execution default-cli of goal io.fabric8:docker-maven-plugin:0.20.1:build failed.
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:212)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
        at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
        at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
        at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307)
        at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193)
        at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106)
        at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
        at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
        at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
        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.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
        at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
        at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
        at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: org.apache.maven.plugin.PluginExecutionException: Execution default-cli of goal io.fabric8:docker-maven-plugin:0.20.1:build failed.
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:145)
        at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:207)
        ... 20 more
Caused by: java.lang.NullPointerException
        at io.fabric8.maven.docker.access.DockerConnectionDetector$ConnectionParameter.initCertPath(DockerConnectionDetector.java:171)
        at io.fabric8.maven.docker.access.DockerConnectionDetector$ConnectionParameter.<init>(DockerConnectionDetector.java:146)
        at io.fabric8.maven.docker.access.DockerConnectionDetector$UnixSocketDockerHostProvider.getConnectionParameter(DockerConnectionDetector.java:110)
        at io.fabric8.maven.docker.access.DockerConnectionDetector.detectConnectionParameter(DockerConnectionDetector.java:78)
        at io.fabric8.maven.docker.service.DockerAccessFactory.createDockerAccess(DockerAccessFactory.java:37)
        at io.fabric8.maven.docker.AbstractDockerMojo.execute(AbstractDockerMojo.java:220)
        at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
        ... 21 more

[rhuss]

Thanks for reporting this. It seems that the directory ~/.docker exist for you as a directory but is not readable by the d-m-p process. (This directory is checked for certificates).

I adapted the error message to reflect this situation better.