maven-central-publish

---

name: maven-central-publish description: "Comprehensive guide and toolkit for publishing Java artifacts to Maven Central using the modern Central Portal (central.sonatype.com) workflow." version: 1.0.0 metadata: openclaw: emoji: "📦" category: publishing clawhub: requires: bins: ["maven", "gpg"]

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Maven Central Publish Skill

This skill provides a standardized workflow for publishing Java/Kotlin libraries to the Maven Central Repository using the modern Central Portal (via central-publishing-maven-plugin).

📋 Prerequisites

1. Central Portal Account: Sign up at central.sonatype.com. 2. Namespace Verified: You must have verified your groupId (e.g., io.github.username or com.yourdomain) in the portal. 3. User Token: Generated from the Central Portal (My Account -> Generate User Token).

🛠️ Environment Setup

1. Install Tools

Ensure maven, gnupg, and openjdk-17+ are installed.

# Ubuntu/Debian
apt-get install -y maven gnupg openjdk-17-jdk

2. GPG Configuration (Critical)

Maven requires GPG signing. For automated/headless environments, Loopback Pinentry is required.

# 1. Generate Key (if none exists)
gpg --gen-key
2. Configure Loopback (Prevent UI prompts)
mkdir -p ~/.gnupg
echo "allow-loopback-pinentry" >> ~/.gnupg/gpg-agent.conf
echo "pinentry-mode loopback" >> ~/.gnupg/gpg.conf
gpg-connect-agent reloadagent /bye
3. Publish Key
gpg --list-keys # Get your Key ID (last 8 chars or full hex)
gpg --keyserver keyserver.ubuntu.com --send-keys 

3. Maven Settings (~/.m2/settings.xml)

Configure your Central Portal credentials.

  
    
      central
      USER_TOKEN_USERNAME
      USER_TOKEN_PASSWORD
    
  
  
    
      release
      
        false
      
      
        gpg
        YOUR_GPG_PASSPHRASE
      
    
  

📦 Project Configuration (pom.xml)

Your project MUST meet the Quality Requirements: 1. Coordinates: groupId, artifactId, version. 2. Metadata: name, description, url, licenses, developers, scm. 3. Plugins: Javadoc, Source, GPG, and Central Publishing.

Recommended Plugin Configuration

Add this to your section:

    org.apache.maven.plugins
    maven-source-plugin
    3.3.0
    
        
            attach-sources
            jar-no-fork
        
    


    org.apache.maven.plugins
    maven-javadoc-plugin
    3.6.3
    
        none 
        false
    
    
        
            attach-javadocs
            jar
        
    


    org.apache.maven.plugins
    maven-gpg-plugin
    3.1.0
    
        
            --pinentry-mode
            loopback
        
    
    
        
            sign-artifacts
            verify
            sign
        
    


    org.sonatype.central
    central-publishing-maven-plugin
    0.7.0
    true
    
        central
        
        false 
    

🚀 Deployment

Run the deploy command with the release profile active:

mvn clean deploy -P release

Success Indicators:

[INFO] Uploaded bundle successfully...

[INFO] Deployment ... has been validated.

If autoPublish is false (recommended for first time), log in to central.sonatype.com, review the deployment, and click Publish.

❓ Troubleshooting

| Error | Cause | Fix | |-------|-------|-----| | 401 Unauthorized | Invalid User Token in settings.xml | Generate new token in Central Portal. Ensure server ID matches. | | GPG signing failed | No pinentry / wrong passphrase | Use pinentry-mode loopback config; Check gpg-agent. | | Javadoc generation failed | Strict HTML checks | Add none to javadoc plugin config. | | Invalid coordinates | GroupId mismatch | Ensure pom.xml groupId matches verified namespace in Portal. |