Publishing Android library to the GitHub Package Registry

build.gradle

apply plugin: 'maven-publish' // Apply this plugin at the top of your library build.gradle

def githubProperties = new Properties()
githubProperties.load(new FileInputStream(rootProject.file("github.properties"))) //Set env variable GPR_USER & GPR_API_KEY if not adding a properties file

def getVersionName = { ->
 return "1.0.2" // Replace with version Name
}

def getArtificatId = { ->
 return "sampleAndroidLib" // Replace with library name ID
}

publishing {
 publications {
   bar(MavenPublication) {
      groupId 'com.enefce.libraries' // Replace with group ID
      artifactId getArtificatId()
      version getVersionName()
      artifact("$buildDir/outputs/aar/${getArtificatId()}-release.aar")
    }
 }
 
repositories {
        maven {
               name = "GitHubPackages"
        /** Configure path of your package repository on Github
         ** Replace GITHUB_USERID with your/organisation Github userID       
         ** and REPOSITORY with the repository name on GitHub
        */
 url = uri("https://maven.pkg.github.com/GITHUB_USERID/REPOSITORY")
credentials {
        /** Create github.properties in root project folder file with     
         ** gpr.usr=GITHUB_USER_ID & gpr.key=PERSONAL_ACCESS_TOKEN 
         ** Set env variable GPR_USER & GPR_API_KEY if not adding a properties file**/
 
         username = githubProperties['gpr.usr'] ?: System.getenv("GPR_USER")
         password = githubProperties['gpr.key'] ?: System.getenv("GPR_API_KEY")
      }
    }
  }
}

Typo alert: . after 'maven-publish'

Corrected. Thank you Shauvik.