Usage

The following examples describe the basic usage of the Reproducible Build Maven plugin.

Fix build artifacts to make them reproducible

To execute the plugin during the pre-integration-test phase (just after the package phase), add the Reproducible Build Maven plugin in the <build> section of your pom.xml.

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>io.github.zlika</groupId>
        <artifactId>reproducible-build-maven-plugin</artifactId>
        <version>0.16</version>
        <executions>
          <execution>
            <goals>
              <goal>strip-jar</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  ...
</project>

Normalize ObjectFactory.java files generated by the JAXB xjc tool

To execute the plugin during the process-sources phase, add the Reproducible Build Maven plugin in the <build> section of your pom.xml.

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>io.github.zlika</groupId>
        <artifactId>reproducible-build-maven-plugin</artifactId>
        <version>0.16</version>
        <executions>
          <execution>
            <goals>
              <goal>strip-jaxb</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  ...
</project>

Make reproducible archives with maven-assembly-plugin

If you use maven-assembly-plugin to create a ZIP/TAR/TAR.GZ/TAR.BZ2 archive during your build, you need to execute the strip-jar goal twice, one before the maven-assembly-plugin single goal (to strip the main artifact of the build before inclusion in the archive), and a second time after the maven-assembly-plugin single goal (to strip the non-reproducible elements of the archive format itself).

NOTE: When several plugins/goals are defined to run during the same phase, Maven runs them in their declaration order in the pom, so you must declare reproducible-build-maven-plugin BEFORE maven-assembly-plugin.

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>io.github.zlika</groupId>
        <artifactId>reproducible-build-maven-plugin</artifactId>
        <version>0.16</version>
        <executions>
          <execution>
            <id>strip-jar</id>
            <phase>package</phase>
            <goals>
              <goal>strip-jar</goal>
            </goals>
          </execution>
          <execution>
            <id>strip-archive</id>
            <phase>pre-integration-test</phase>
            <goals>
              <goal>strip-jar</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
      
      <plugin>
        <artifactId>maven-assembly-plugin</artifactId>
        <configuration>
          <descriptors>
            <descriptor>assembly.xml</descriptor>
          </descriptors>
        </configuration>
        <executions>
          <execution>
            <id>make-assembly</id>
            <phase>package</phase>
            <goals>
              <goal>single</goal>
            </goals>
          </execution>
        </executions>
      </plugin>      
    </plugins>
  </build>
  ...
</project>

Use last commit time as timestamp for zip (jar) entries (since version 0.6)

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>pl.project13.maven</groupId>
        <artifactId>git-commit-id-plugin</artifactId>
        <executions>
          <execution>
            <id>retrieve-git-info</id>
            <phase>prepare-package</phase>
            <goals>
              <goal>revision</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <injectAllReactorProjects>true</injectAllReactorProjects>
          <runOnlyOnce>true</runOnlyOnce>
          <skipPoms>false</skipPoms>
          <dateFormat>yyyyMMddHHmmss</dateFormat>
          <dateFormatTimeZone>UTC</dateFormatTimeZone>
        </configuration>
      </plugin>
      
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-jar-plugin</artifactId>
        <configuration>
          <archive>
            <manifestEntries>
              <Last-Commit-Id>${git.commit.id}</Last-Commit-Id>
              <Last-Commit-Time>${git.commit.time}</Last-Commit-Time>
              <Reproducible-Build>true</Reproducible-Build>
            </manifestEntries>
          </archive>
        </configuration>
      </plugin>
      
      <plugin>
        <groupId>io.github.zlika</groupId>
        <artifactId>reproducible-build-maven-plugin</artifactId>
        <version>0.16</version>
        <executions>
          <execution>
            <id>strip-jaxb</id>
            <goals>
              <goal>strip-jaxb</goal>
            </goals>
          </execution>
          <execution>
            <id>strip-jar</id>
            <goals>
              <goal>strip-jar</goal>
            </goals>
            <configuration>
              <zipDateTime>${git.commit.time}</zipDateTime>
              <!-- Set custom date/time format pattern, "yyyyMMddHHmmss" by default -->
              <!-- <zipDateTimeFormatPattern>yyyyMMddHHmmss</zipDateTimeFormatPattern> -->
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  ...
</project>

Include/Exclude files (since version 0.13)

Each filename that the plugin inspects for stripping is first passed to a series of inclusion filters, and then to a series of exclusion filters. The filters are expressed as standard java.util.Pattern regular expressions. If the filename matches at least one inclusion filter, then it becomes a candidate for stripping. If the candidate filename matches at least one exclusion filter, then the file is no longer a candidate for stripping. By default, the plugin behaves as if no exclusion filter was provided, and exactly one inclusion filter was provided that matches all input (.*).

An example that will include all example-*.jar files except for example-excluded.jar:

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>io.github.zlika</groupId>
        <artifactId>reproducible-build-maven-plugin</artifactId>
        <version>0.16</version>
        <executions>
          <execution>
            <id>strip-jar</id>
            <goals>
              <goal>strip-jar</goal>
            </goals>
            <configuration>
              <includes>
                <include>example-.*\.jar</include>
              </includes>
              <excludes>
                <exclude>example-excluded.jar</exclude>
              </excludes>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  ...
</project>