Maven Central Publish Action

A GitHub Action for publishing libraries to Maven Central using the Vanniktech Maven Publish Plugin.

This action automates:

• Publishing artifacts to Maven Central
• Generating and publishing documentation with Dokka
• Creating GitHub releases
• Updating version in gradle.properties

Usage

name: Publish Release

on:
  workflow_dispatch:
    inputs:
      version:
        description: 'Version to publish'
        required: true

jobs:
  publish:
    runs-on: macos-latest
    permissions:
      contents: write
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        
      - name: Publish to Maven Central
        uses: openMF/[email protected]
        with:
          version: ${{ github.event.inputs.version }}
          maven-central-username: ${{ secrets.MAVEN_CENTRAL_USERNAME }}
          maven-central-password: ${{ secrets.MAVEN_CENTRAL_PASSWORD }}
          gpg-key-id: ${{ secrets.GPG_SIGNING_KEY_ID }}
          gpg-key: ${{ secrets.GPG_SIGNING_KEY }}
          gpg-passphrase: ${{ secrets.GPG_PASSPHRASE }}
          github-token: ${{ secrets.GITHUB_TOKEN }}

Prerequisites

1. Central Portal account
2. Registered namespace
3. GPG key for signing artifacts
4. Vanniktech Maven Publish Plugin configured in your project

Required Secrets

Configure these secrets in your repository:

• MAVEN_CENTRAL_USERNAME: Your Maven Central username
• MAVEN_CENTRAL_PASSWORD: Your Maven Central password/token
• GPG_SIGNING_KEY_ID: Your GPG key ID (last 8 characters of key fingerprint)
• GPG_SIGNING_KEY: Your ASCII-armored GPG private key
• GPG_PASSPHRASE: Your GPG key passphrase (if applicable)
• GITHUB_TOKEN: GitHub automatically provides this secret in workflows

These secrets must be passed to the action explicitly in your workflow as shown in the example above.

Note: You'll need to set the permissions: contents: write in your job if creating GitHub releases and publishing documentation.

To export your GPG key in ASCII-armored format:

gpg --export-secret-keys --armor KEY_ID

Inputs

Input	Description	Required	Default
version	Version to publish	Yes	N/A
maven-central-username	Maven Central username	Yes	N/A
maven-central-password	Maven Central password/token	Yes	N/A
gpg-key-id	GPG signing key ID	Yes	N/A
gpg-key	GPG signing key (ASCII-armored)	Yes	N/A
gpg-passphrase	GPG key passphrase	Yes	''
github-token	GitHub token for releases & docs	Yes	N/A
java-version	Java version	No	17
java-distribution	Java distribution	No	zulu
publish-dokka-docs	Publish Dokka docs	No	true
create-github-release	Create GitHub release	No	true
update-gradle-properties	Update gradle.properties	No	true
working-directory	Project directory	No	.
gradle-publish-task	Gradle publish task	No	publishAllPublicationsToMavenCentralRepository
dokka-html-task	Documentation task	No	dokkaHtml
docs-folder	Docs output folder	No	build/dokka/html
sonatype-host	Sonatype host	No	CENTRAL_PORTAL
automatic-release	Auto-release from staging	No	true

Plugin Configuration

Add the Vanniktech Maven Publish Plugin to your project:

// build.gradle.kts
plugins {
    id("com.vanniktech.maven.publish") version "0.25.3"
}

// Configure the plugin
mavenPublishing {
    publishToMavenCentral(SonatypeHost.CENTRAL_PORTAL)
    signAllPublications()
    
    pom {
        // Your POM configuration
    }
}

Or using gradle.properties:

GROUP=com.example.mylibrary
POM_ARTIFACT_ID=mylibrary-runtime
# VERSION_NAME will be set by the GitHub Action
POM_NAME=My Library
POM_DESCRIPTION=A description of the library
POM_URL=https://github.com/username/mylibrary/
# License information
POM_LICENSE_NAME=The Apache Software License, Version 2.0
POM_LICENSE_URL=https://www.apache.org/licenses/LICENSE-2.0.txt
POM_LICENSE_DIST=repo
# SCM information
POM_SCM_URL=https://github.com/username/mylibrary/
POM_SCM_CONNECTION=scm:git:git://github.com/username/mylibrary.git
POM_SCM_DEV_CONNECTION=scm:git:ssh://[email protected]/username/mylibrary.git
# Developer information
POM_DEVELOPER_ID=username
POM_DEVELOPER_NAME=Your Name
POM_DEVELOPER_URL=https://github.com/username/

Publishing Snapshots

To publish a snapshot version, use a version ending with -SNAPSHOT. The action will publish it to the snapshot repository.

License

MIT License

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[!Info] For detailed information about all configuration options, please visit the Vanniktech Maven Publish Plugin documentation. This documentation includes advanced settings for POM configuration, publication targets, and signing requirements.