feat(sdk): setup publishing to maven central repository

.github/workflows/ci.yaml

@@ -1,4 +1,4 @@
-name: CI
+name: CI/CD
 
 on:
   pull_request:
@@ -7,7 +7,7 @@ on:
     branches: ["main"]
 
 jobs:
-  main:
+  ci:
     name: CI
     runs-on: ubuntu-latest
     strategy:
@@ -36,3 +36,25 @@ jobs:
       - name: Publish to local maven repo
         run: make install
 
+  cd:
+    name: CD
+    runs-on: ubuntu-latest
+    if: ${{ github.ref_name == 'main' }}
+    needs: [ci]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v5
+        with:
+          fetch-depth: 0
+
+      - name: Create git tags and publish to Maven Central
+        env:
+          GPG_SIGNING_KEY: "${{ secrets.GPG_SIGNING_KEY }}"
+          GPG_SIGNING_PASSWORD: "${{ secrets.GPG_SIGNING_PASSWORD }}"
+          ORG_GRADLE_PROJECT_mavenCentralUsername: "${{ secrets.MAVEN_CENTRAL_USERNAME }}"
+          ORG_GRADLE_PROJECT_mavenCentralPassword: "${{ secrets.MAVEN_CENTRAL_PASSWORD }}"
+        run: |
+          git config --global user.name "SDK Releaser Bot"
+          git config --global user.email "noreply@stackit.de"
+          ./scripts/publish.sh
+

CHANGELOG.md

@@ -0,0 +1,8 @@
+## Release (2025-MM-DD)
+- `core`: [v0.1.0](core/CHANGELOG.md#v010)
+  - Initial onboarding of STACKIT Java SDK core lib
+- `iaas`: [v0.1.0](services/iaas/CHANGELOG.md#v010)
+  - Initial onboarding of STACKIT Java SDK for IaaS service
+- `resourcemanger`: [v0.1.0](services/resourcemanager/CHANGELOG.md#v010)
+  - Initial onboarding of STACKIT Java SDK for Resourcemanager service
+

build.gradle

@@ -1,12 +1,15 @@
 plugins {
 	id 'java'
-	id 'maven-publish'
+	id 'signing'
 	id 'idea'
 	id 'eclipse'
 
 	id 'com.diffplug.spotless' version '6.21.0'
-}
 
+	/* We have to use this 3rd party plugin for publishing to MavenCentral because as of AUG-2025 there is no official
+	 * plugin which supports publishing to MavenCentral Portal. */
+	id "com.vanniktech.maven.publish.base" version "0.34.0"
+}
 
 allprojects {
 	apply plugin: 'com.diffplug.spotless'
@@ -63,86 +66,118 @@ allprojects {
 	}
 }
 
+def configureMavenCentralPublishing(Project project) {
+	project.plugins.withId('com.vanniktech.maven.publish.base') {
+		project.mavenPublishing {
+			publishToMavenCentral(true) // publish automatically after upload to Maven Central
+		}
+	}
+}
+
 subprojects {
 	apply plugin: 'java'
-	apply plugin: 'maven-publish'
 	apply plugin: 'idea'
 	apply plugin: 'eclipse'
 
-	group = 'cloud.stackit'
-
-	afterEvaluate { project ->
-		// only apply to service sub-projects and core
-		if (project.path.startsWith(':services:') || project.name == "core" ) {
-			// override the version of each service with the ones obtained from the VERSION files
-			def versionFile = project.file("VERSION")
-			if (versionFile.exists()) {
-				try {
-					version = versionFile.text.trim()
-				} catch (IOException e) {
-					version = 'SNAPSHOT'
-					logger.error("Could not read VERSION file for project '${project.path}': ${e.message}")
-				}
-			} else {
+	group = 'cloud.stackit.sdk'
+
+	// only apply to service sub-projects and core
+	if (project.path.startsWith(':services:') || project.name == "core" ) {
+		apply plugin: 'signing'
+		apply plugin: 'com.vanniktech.maven.publish.base'
+
+		// override the version of each service with the ones obtained from the VERSION files
+		def versionFile = project.file("VERSION")
+		if (versionFile.exists()) {
+			try {
+				version = versionFile.text.trim()
+			} catch (IOException e) {
 				version = 'SNAPSHOT'
-				logger.warn("VERSION file not found in project '${project.path}'. Skipping version setting.")
+				logger.error("Could not read VERSION file for project '${project.path}': ${e.message}")
 			}
+		} else {
+			version = 'SNAPSHOT'
+			logger.warn("VERSION file not found in project '${project.path}'. Skipping version setting.")
+		}
 
+		java {
+			withSourcesJar()
+			withJavadocJar()
+		}
 
-			publishing {
-				publications {
-					maven(MavenPublication) {
-						artifactId = "stackit-sdk-${project.name}"
-						from components.java
-
-						pom {
-							name.set(project.name)
-							description.set("STACKIT Java SDK for the ${project.name} service")
-							url.set("https://github.com/stackitcloud/stackit-sdk-java/tree/main/services/${rootProject.name}")
-							licenses {
-								license {
-									name.set("Apache License, Version 2.0")
-									url.set("https://www.apache.org/licenses/LICENSE-2.0.txt")
-								}
-							}
-							developers {
-								developer {
-									id.set("stackitcloud") // TODO: not clear which value must be placed here, check this when setting up publishment to Maven Central
-									name.set("STACKIT Developer Tools")
-									email.set("developer-tools@stackit.cloud")
-								}
+		// don't fail on missing javadoc strings
+		tasks.withType(Javadoc).configureEach {
+			options.addStringOption('Xdoclint:none', '-quiet')
+		}
+
+		publishing {
+			publications {
+				mavenJava(MavenPublication) {
+					artifactId = "${project.name}"
+					from components.java
+
+					pom {
+						name.set(project.name)
+						description.set("STACKIT Java SDK for the ${project.name} service")
+						url.set("https://github.com/stackitcloud/${rootProject.name}/tree/main/services/${project.name}")
+						licenses {
+							license {
+								name.set("Apache License, Version 2.0")
+								url.set("https://www.apache.org/licenses/LICENSE-2.0.txt")
 							}
-							scm {
-								connection.set("scm:git:git://github.com/stackitcloud/${rootProject.name}.git")
-								developerConnection.set("scm:git:ssh://github.com/stackitcloud/${rootProject.name}.git")
-								url.set("https://github.com/stackitcloud/${rootProject.name}")
+						}
+						developers {
+							developer {
+								id.set("stackitcloud")
+								name.set("STACKIT Developer Tools")
+								email.set("developer-tools@stackit.cloud")
 							}
 						}
+						scm {
+							connection.set("scm:git:git://github.com/stackitcloud/${rootProject.name}.git")
+							developerConnection.set("scm:git:ssh://github.com/stackitcloud/${rootProject.name}.git")
+							url.set("https://github.com/stackitcloud/${rootProject.name}")
+						}
 					}
 				}
-				repositories {
-					mavenLocal()
-				}
+			}
+
+			repositories {
+				mavenLocal()
 			}
 		}
 
-		// only apply to example sub-projects
-		if (project.path.startsWith(':examples:')) {
-			if (!project.hasProperty('mainClassName')) {
-				logger.warn("'mainClassName' property not defined for subproject '${project.path}'. Skipping execution of this task.")
+		signing {
+			required {
+				// signing is only required if the artifacts are to be published to Maven Central
+				gradle.taskGraph.hasTask(":services:${project.name}:publishToMavenCentral") || gradle.taskGraph.hasTask(":${project.name}:publishToMavenCentral")
 			}
 
-			tasks.register('execute', JavaExec) {
-				if (!project.hasProperty('mainClassName')) {
-					doLast {
-						logger.warn("'mainClassName' property not defined for subproject '${project.path}'. Skipping execution of this task.")
-					}
-					enabled = false // Disable the task if no main class is specified
-					return
+			def signingKey = System.getenv("GPG_SIGNING_KEY") ?: findProperty("signingKey")
+			def signingPassword = System.getenv("GPG_SIGNING_PASSWORD") ?: findProperty("signingPassword")
+			useInMemoryPgpKeys(signingKey as String, signingPassword as String)
+			sign publishing.publications.mavenJava
+		}
+
+		configureMavenCentralPublishing(project)
+	}
+
+	// only apply to example sub-projects
+	if (project.path.startsWith(':examples:')) {
+		if (!project.hasProperty('mainClassName')) {
+			logger.warn("'mainClassName' property not defined for subproject '${project.path}'. Skipping execution of this task.")
+		}
+
+		tasks.register('execute', JavaExec) {
+			if (!project.hasProperty('mainClassName')) {
+				doLast {
+					logger.warn("'mainClassName' property not defined for subproject '${project.path}'. Skipping execution of this task.")
 				}
-				mainClass = project.mainClassName
-				classpath = sourceSets.main.runtimeClasspath
+				enabled = false // Disable the task if no main class is specified
+				return
 			}
+			mainClass = project.mainClassName
+			classpath = sourceSets.main.runtimeClasspath
 		}
 	}
 

core/CHANGELOG.md

@@ -0,0 +1,2 @@
+## v0.1.0
+- Initial onboarding of STACKIT Java SDK core lib

core/VERSION

@@ -1 +1 @@
-0.0.1-SNAPSHOT
+0.1.0

scripts/publish.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+
+# This script creates the git tags and publishes the artifacts to Maven Central
+
+# Immediate exit on failure
+set -e
+
+# VERSION contains only one single line which contains the version of the service
+# in the following format e.g. 0.3.0
+
+# iterate over all services and core by their VERSION files
+for file in $(find . -printf '%P\n' | grep -E "(^services/[^/]+/VERSION$|^core/VERSION$)"); do
+
+    # Extract the current version and build the expected tag
+    dirpath=$(dirname "$file")
+    version_path="$dirpath/VERSION"
+    gradle_subproject="${dirpath//\//:}" # replace "/" with ":"
+    version=$(<"$version_path")
+    expected_tag="$dirpath/v$version"
+
+    printf "\n============================================================================================\n\n"
+
+    # Check if the tag already exists
+    if git rev-parse --verify "$expected_tag" &> /dev/null; then
+        echo "Tag '$expected_tag' already exists. Skipping tag creation and gradle publish..."
+    else
+        # Tag doesn't exist. Create a tag and push it.
+        echo "Tag '$expected_tag' does not exist."
+        git tag -a $expected_tag -m "Release $version"
+        git push origin tag $expected_tag
+
+        ./gradlew "${gradle_subproject}:publishToMavenCentral"
+    fi
+done

services/iaas/CHANGELOG.md

@@ -0,0 +1,2 @@
+## v0.1.0
+- Initial onboarding of STACKIT Java SDK for IaaS service

services/iaas/VERSION

@@ -0,0 +1 @@
+0.1.0

services/resourcemanager/CHANGELOG.md

@@ -0,0 +1,2 @@
+## v0.1.0
+- Initial onboarding of STACKIT Java SDK for Resourcemanager service

services/resourcemanager/VERSION

@@ -1 +1 @@
-0.0.1-SNAPSHOT
+0.1.0