springboot Provide finer-grained control over the automatically generated build info properties

In light of the efforts of #8391 ... builds can be reproducible, however...

In Spring Boot 2.0.0.RC1 if you are using:

springBoot {
   buildInfo()
}

In your build.gradle file... the build jar files are not binary equal. The plug-in includes the build.time property and there isn't an obvious way to turn that off.

This is in the build/resources/main/META-INF/build-info.properties file.

Possible suggestions for remedy: 1. Allow the timestamp to be set to the time of the VCS commit. 2. Allow the timestamp to be set to a "release time" fixed value. 3. Allow the timestamp to be null or omitted entirely.

Comment From: wilkinsona

You can remove unwanted properties from the auto-generated build-info.properties file by post-processing it. The following example removes build.time:

springBoot {
    buildInfo {
        doLast {
            File propertiesFile = new File(destinationDir, 'build-info.properties')
            Properties properties = new Properties()
            propertiesFile.withInputStream { properties.load(it)}
            properties.remove('build.time')
            propertiesFile.withOutputStream { properties.store(it, 'UTF-8') }
        }
    }
}

Comment From: jzampieron

Thanks.

Comment From: schnapster

For people like me who just copypasta stuff from Github issues they stumble upon:

The above approach didn't work for me (Spring Boot v2.2.4). For some reason a timestamp was still written into the file, just as a comment at the top of the file.

This is what worked:

springBoot {
    buildInfo {
        properties {
            time = null
        }
    }
}

You can also set it to something else than null as long as it is constant between reruns of the same code. For a bit more fancy usage, you could use a Gradle git plugin and fetch the timestamp from the last commit for example.