Add github-packages publishing

.github/workflows/gradle.yml

@@ -6,15 +6,15 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
       with: 
         submodules: recursive
     - name: Set up Java 11
       uses: actions/setup-java@v1
       with:
         java-version: 11
     - name: Build with Gradle
-      run: ./gradlew build
+      run: ./gradlew clean build test
     - uses: actions/upload-artifact@v2-preview
       with:
         name: artifact

.github/workflows/publish.yml

@@ -0,0 +1,22 @@
+name: Java CI
+
+on:
+  release:
+    types: [ published ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+      with: 
+        submodules: recursive
+    - name: Set up Java 11
+      uses: actions/setup-java@v1
+      with:
+        java-version: 11
+    - name: Build with Gradle
+      env:
+        GITHUB_USERNAME: ${{ secrets.github.actor }}
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      run: ./gradlew clean build test publish

build.gradle.kts

@@ -3,6 +3,7 @@ import java.io.IOException
 plugins {
     java
     `java-library`
+    `maven-publish`
     id("com.diffplug.spotless") version "6.1.2"
 }
 
@@ -88,3 +89,23 @@ tasks.processResources {
         )
     }
 }
+
+publishing {
+    repositories {
+        maven {
+            name = "GitHubPackages"
+            url = uri("https://maven.pkg.github.com/BlueMap-Minecraft/BlueMapAPI")
+            credentials {
+                username = project.findProperty("gpr.user") as String? ?: System.getenv("GITHUB_USERNAME")
+                password = project.findProperty("gpr.key") as String? ?: System.getenv("GITHUB_TOKEN")
+            }
+        }
+    }
+
+    publications {
+        register<MavenPublication>("gpr") {
+            from(components["java"])
+            artifactId = "BlueMapAPI"
+        }
+    }
+}