❯ Guillaume Laforge

Serverless tip #1 — Deploy a standalone JVM web app with Gradle and the App Engine plugin

google-cloud app-engine serverless gradle java tips

Requirements:

  • an existing Google Cloud Platform account and project
  • a Java or alternative language web application
  • a Gradle build that creates a standalone executable JAR file

In youd build.gradle file, add the App Engine gradle plugin to your buildscript dependencies:

buildscript {
    repositories {
        jcenter()
        mavenCentral()
    }
    dependencies {
        classpath 'com.google.cloud.tools:appengine-gradle-plugin:2.+'
    }
}

Apply the plugin, to make use of it:

apply plugin: "com.google.cloud.tools.appengine-appyaml"

Then you can configure the appengine task to point at the standalone executable JAR:

appengine {
    stage.artifact = 
            "${buildDir}/libs/${project.name}-${project.version}.jar"
    deploy {
        projectId = "YOUR-PROJECT-ID"
        version = "1"
    }
}

You can customize the path of the artifact, specify the project ID outside, or define an App Engine version that’s dependent on your project version, a git commit, etc.

Note that the App Engine gradle plugin expects to find the app.yaml configuration file in src/main/appengine.

You can then deploy your application with:

$ ./gradlew appengineDeploy

More information: