Fission: Java and JVM Environment
This is the JVM environment for Fission.
It's a Docker image containing a OpenJDK8 runtime, along with a dynamic loader. A few dependencies are included in the pom.xml file.
Looking for ready-to-run examples? See the JVM examples directory.
Customizing this image
To add package dependencies, edit pom.xml to add what you need, and rebuild this image (instructions below).
Rebuilding and pushing the image
You'll need access to a Docker registry to push the image: you can sign up for Docker hub at hub.docker.com, or use registries from gcr.io, quay.io, etc. Let's assume you're using a docker hub account called USER. Build and push the image to the the registry:
docker build -t USER/jvm-env . && docker push USER/jvm-env
Using the image in fission
You can add this customized image to fission with "fission env create":
fission env create --name jvm --image USER/jvm-env
Or, if you already have an environment, you can update its image:
fission env update --name jvm --image USER/jvm-env
After this, fission functions that have the env parameter set to the same environment name as this command will use this environment.
Web Server Framework
JVM environment uses Tomcat HTTP server by default as it is included in spring web. You can choose to use jetty or undertow by changing the dependency in pom.xml file as shown below.
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<exclusions>
<!-- Exclude the Tomcat dependency -->
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
</exclusion>
</exclusions>
</dependency>
<!-- Use Jetty instead -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jetty</artifactId>
</dependency>
Java and JVM builder
JVM environment builder is based on OpenJDK8 and Maven 3.5.4 version. The default build command runs mvn clean package and uses the target/*with-dependencies.jar file for function. The default build command can be overridden as long as the uber jar file is copied to ${DEPLOY_PKG}.