Maven offline - problem with mvn-plugins

Question

I'm using maven in my project and I need to run the build in a non-internet-access machine.

When I test my project build everything is working, but when I run the build in a future moment, the maven try to update the mvn-plugins and this sht* is broking my build.

My config file: settings.xml from mvn.

    <profile>
      <id>blaProfile</id>
      <repositories>
        <repository>
          <id>blaRepo</id>
          <url>file://${bla.3rdParty.home}/maven/.m2/repository</url>
          <layout>default</layout>
        </repository>
      </repositories>
      <pluginRepositories>
        <pluginRepository>
          <id>blaRepo</id>
          <url>file://${bla.3rdParty.home}/maven/.m2/repository</url>
          <layout>default</layout>
        </pluginRepository>
      </pluginRepositories>
    </profile>

  <activeProfiles>
    <activeProfile>blaProfile</activeProfile>
  </activeProfiles>

And I ran my maven is with the params:

mvn -npu -bla.3rdParty.home="$(THE_CORRECT_PATH)" package

I saw that maven try to update some mvn-plugins for some time, but the option:

-npu,--no-plugin-updates      Suppress upToDate check for any relevant

Should work for this updates.

Well waiting some help on that!

Thanks in advance!

---

UPDATE(1):
What I'm looking at, is that I could use the setting:

<usePluginRegistry>true</usePluginRegistry>

Inside my settings.xml and with this, I'll have a plugin-registry.xml inside ${user.home}/.m2 that I can config and force the maven plugins versions.

But it's not working! :(

Answer 1

In order to cache plugins into the .m2/repository folder you would need to specify all plugins explicitly with the mvn <maven-plugin-name>:help

You would also need to specify explicit version for each plugin in the <plugins> or <pluginsManagement> section of your pom.xml

<plugin> 
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-surefire-plugin</artifactId>
  <version>2.19</version>
  <dependencies>
    <dependency>
      <groupId>org.apache.maven.surefire</groupId>
      <artifactId>surefire-testng</artifactId>
      <version>2.19</version>
    </dependency>
  </dependencies>
</plugin>

This is needed to make sure that mvn install -o uses the same plugin version.

Ofcourse you would also need to run mvn dependency:go-offline to take care of your compile and test dependencies.

mvn assembly:help compiler:help enforcer:help exec:help failsafe:help install:help jar:help resources:help surefire:help mvn dependency:go-offline mvn compile --offline

Answer 2

Maven Go-offline + Isolated Docker Multi-stage Image Builds

My answer is for both a local build or a Dockerized environment, which is isolated on the nature of how docker images are built. This uses Maven 3.6.3-jdk-8.

With this answer, you know exactly how much time your CI spends on downloading, compiling, testing, packaging...

Finally, also answering to the old question on Jira for the go-offline https://issues.apache.org/jira/browse/MDEP-82?focusedCommentId=16997793&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-16997793

• Update pom.xml dependencies
  • maven-dependency-plugin
  • surefire-junit-platform
• Call go-offline resolving dependencies
• Call any mvn command with the switch --off-line

Set latest versions of the plugins

@@ -23,6 +23,9 @@
         <junit-jupiter.version>5.5.2</junit-jupiter.version>
         <common-io.version>2.6</common-io.version>
         <jacoco-maven-plugin.version>0.8.4</jacoco-maven-plugin.version>
+        <!-- https://issues.apache.org/jira/browse/MDEP-82 -->
+        <maven-dependency-plugin.version>3.1.1</maven-dependency-plugin.version>
+        <surefire-junit-platform.version>2.22.2</surefire-junit-platform.version>
         <maven-release-plugin.version>2.5.3</maven-release-plugin.version>
         <maven-deploy-plugin.version>2.8.2</maven-deploy-plugin.version>
         <maven-surefire-report-plugin.version>2.22.2</maven-surefire-report-plugin.version>
...
...
     <build>
         <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-dependency-plugin</artifactId>
+                <version>${maven-dependency-plugin.version}</version>
+            </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
@@ -135,6 +143,11 @@
                     <target>${java.version}</target>
                 </configuration>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.surefire</groupId>
+                <artifactId>surefire-junit-platform</artifactId>
+                <version>${surefire-junit-platform.version}</version>
+            </plugin>

Create the Go-offline cache

• This will ensure all the dependencies are downloaded
• More than 3m to download all dependencies

FROM maven:3.6.3-jdk-8 AS dependencies-downloaded
...
...
COPY pom.xml /usr/src/app/pom.xml
COPY settings.xml /usr/src/app/settings.xml
WORKDIR /usr/src/app
RUN mvn -f pom.xml -s settings.xml dependency:resolve-plugins dependency:go-offline

Call compile with --offline

• We can reuse the same image for compilation
• Only takes 7s because nothing is downloaded

FROM dependencies-downloaded AS compile
COPY app /usr/src/app
WORKDIR /usr/src/app
RUN mvn -f pom.xml -s settings.xml compile --offline

Call tests with --offline

• We can reuse the same image for tests
• Taking 18s to run the test cases, without any download whatsoever

FROM compile AS tests
WORKDIR /usr/src/app
RUN mvn -f pom.xml -s settings.xml test --offline

Call package with --offline

• We can reuse the same image for the final jar
• Skipping even the tests ran in the previous docker image
• Taking way less than before

FROM tests AS package
WORKDIR /usr/src/app
RUN mvn -f pom.xml -s settings.xml package -Dmaven.test.skip=true --offline

The final runtime image is a Docker image from the package.

FROM JRE
COPY --from package /usr/src/app/target /bin
...
...