Example Java Functions: Fn Gradle + FDK for Java

This example shows you how to build a Java function by using a Dockerfile.

Key points:

Dockerfile - contains the containerized Docker build (based on dockerhub library/gradle images) and image build - this includes the gradle invocation
The cacheDeps task in build.gradle pulls down dependencies into the container gradle cache to speed up docker builds.
The copyDeps task in build.gradle copies the functions compile deps.
This uses JDK 11 by default

Ensure you have the Fn server running to host your function:

(1) Start the server

$ fn start

(2) Create an app for the function

$ fn create app gradle-build-app

(3) Deploy the function to your app from the gradle-build directory.

fn deploy --app gradle-build-app --local

(4) Invoke the function

fn invoke gradle-build-app gradle_build