Maven: Deploy Artifacts to Nexus - Mincong Huang

Today I’ll talk about how to deploy artifacts to Sonatype Nexus repository using Maven deploy plugin.

Prerequisite

Prepare Nexus server in local:

Download Nexus Repository OSS
Unzip the downloaded file
Start the server
```
$ bin/nexus start
```
Visit http://localhost:8081/
Sign in with username admin and password admin123

Create a Maven project for demo propose:

$ mvn archetype:generate \
  -DgroupId=com.mycompany \
  -DartifactId=demo \
  -DarchetypeArtifactId=maven-archetype-quickstart \
  -DinteractiveMode=false

Declare Maven Deploy Plugin

Declare Maven deploy plugin in the parent POM. It’s the same no matter your project is a single module project or a multi-modules project. The parent pom.xml file is located in project’s root directory.

Define the version of Maven deploy plugin:

<!-- file: /Users/mincong/demo/pom.xml -->
<project>
  ...
  <build>
    ...
    <pluginManagement>
      <plugins>
        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

Use the plugin for deployment:

<!-- file: /Users/mincong/demo/pom.xml -->
<project>
  ...
  <build>
    ...
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-deploy-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

Configure Nexus

Define the ID and URL of your Nexus repository in the project’s parent pom.xml:

<!-- file: /Users/mincong/demo/pom.xml -->
<project>
  ...
  <distributionManagement>
    <snapshotRepository>
      <id>nexus-snapshots</id>
      <url>http://localhost:8081/repository/maven-snapshots/</url>
    </snapshotRepository>
  </distributionManagement>
</project>

Add username and password in Maven global settings (~/.m2/settings.xml):

<!-- file: /Users/mincong/.m2/settings.xml -->
<settings>
  <servers>
    <server>
      <id>nexus-snapshots</id>
      <username>admin</username>
      <password>admin123</password>
    </server>
  </servers>
</settings>

IMPORTANT: You should NOT keep your password in plain text in settings.xml. See Maven official page Password Encryption for the encryption guideline.

Build and Deploy Artifacts

There’re 2 possible solutions: one-step deploy or multi-steps deploy.

One-step deploy runs tests, installation, and deploy in a single command:

$ mvn clean deploy

Multi-steps deploy runs different commands in different steps. Firstly, run install command (which implies comile, test, and install). Once done sucessfully, deploy the results:

$ mvn clean install
$ mvn deploy -DskipTests -Dmaven.install.skip=true

Here’s the comparison of these two solutions:

Item	One-Step Deploy	Multi-Steps Deploy
Maven commands	1 commands	≥ 2 commands
If no test failures, then…	All artifacts deployed	All artifacts deployed
If test failures, then…	Some artifacts deployed ⚠️	No artifacts deployed