Recording .buildinfo File

Recording build result into a .buildinfo file is typically done on command line by calling artifact:buildinfo goal after the normal build:

$ mvn clean verify artifact:buildinfo
[INFO] Scanning for projects...
[INFO] ----------------< org.apache.maven.sample:test-project >----------------
[INFO] Building Test Project 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] --- maven-artifact-plugin:3.5.0:buildinfo (default-cli) @ test-project ---
[INFO] Saved info on build to /tmp/test-project/target/test-project-1.0-SNAPSHOT.buildinfo
[INFO] ------------------------------------------------------------------------
[INFO] ------------------------------------------------------------------------

This records data on the current build results into a .buildinfo file using Reproducible Builds .buildinfo for the JVM format.

Notice that if the build is multi-module, only 1 .buildinfo file is generated, in the last module of the reactor, that will record aggregated results for all the modules.

Checking Reproducible Build: Comparing Current Build Against Previous One

artifact:compare goal compares reference artifacts against current build output to display Reproducible Build output summary:

$ mvn -Papache-release clean verify -Dgpg.skip artifact:compare
[INFO] Scanning for projects...
[INFO] --- maven-artifact-plugin:3.5.0:compare (default-cli) @ doxia-module-markdown ---
[INFO] Saved aggregate info on build to /tmp/doxia-1.9.1/doxia-modules/doxia-module-markdown/target/doxia-module-markdown-1.9.1.buildinfo
[INFO] Checking against reference build from central...
Downloading from central:
[WARNING] Reference buildinfo file not found: it will be generated from downloaded reference artifacts
[INFO] Reference build java.version: 1.8 (from MANIFEST.MF Build-Jdk-Spec)
[ERROR] Current build java.version: 1.7 (from MANIFEST.MF Build-Jdk-Spec)
[INFO] Reference build Unix (from newline)
[INFO] Minimal buildinfo generated from downloaded artifacts: /tmp/doxia-1.9.1/target/reference/doxia-module-markdown-1.9.1.buildinfo
[WARNING] size mismatch doxia-logging-api-1.9.1.jar: investigate with diffoscope target/reference/doxia-logging-api-1.9.1.jar doxia-logging-api/target/doxia-logging-api-1.9.1.jar
[WARNING] size mismatch doxia-module-markdown-1.9.1.jar: investigate with diffoscope target/reference/doxia-module-markdown-1.9.1.jar doxia-modules/doxia-module-markdown/target/doxia-module-markdown-1.9.1.jar
[WARNING] Reproducible Build output summary: 39 files ok, 18 different
[WARNING] see diff target/reference/doxia-module-markdown-1.9.1.buildinfo doxia-modules/doxia-module-markdown/target/doxia-module-markdown-1.9.1.buildinfo
[WARNING] see also
[INFO] Reproducible Build output comparison saved to /tmp/doxia-1.9.1/doxia-modules/doxia-module-markdown/target/doxia-module-markdown-1.9.1.buildcompare
[INFO] Aggregate buildcompare copied to /tmp/doxia-1.9.1/target/doxia-1.9.1.buildcompare