Ballerina Docker Extension

Annotation based docker extension implementation for ballerina.

Features:

• Dockerfile generation based on @docker:Config annotations.
• Docker image generation.
• Docker push support with docker registry.
• Docker based ballerina debug support.
• Copy file support.

Supported Annotations:

@docker:Config{}

• Supported with ballerina services, listeners or functions.

Annotation Name	Description	Default value
name	Name of the Docker image	File name of the generated .jar file
registry	Docker registry url	None
tag	Docker image tag	latest
env	Environment variables for Docker image	None
username	Username for Docker registry	None
password	Password for Docker registry	None
baseImage	Base image to create the Docker image	ballerina/jre8:v1
buildImage	Enable building Docker image	true
push	Enable pushing Docker image to registry	false
enableDebug	Enable debug for ballerina	false
debugPort	Remote debug port	5005
dockerAPIVersion	Docker API Version	None
dockerHost	Docker host IP and docker PORT. ( e.g minikube IP and docker PORT)	DOCKER_HOST environment variable. If DOCKER_HOST is unavailable, uses "unix:///var/run/docker.sock" for Unix or uses "tcp://localhost:2375" for Windows
dockerCertPath	Docker certificate path	"DOCKER_CERT_PATH" environment variable
cmd	Value for CMD for the generated Dockerfile	CMD java -jar ${APP} [--b7a.config.file=${CONFIG_FILE}] [--debug]
dockerConfigFile	Docker config file path	None
uberJar	Use ballerina uber jar	Default is false

@docker:CopyFiles{}

• Supported with ballerina services, listeners or functions.

Annotation Name	Description	Default value
sourceFile	Source path of the file (in your machine)	None
target	Target path (inside container)	None
isBallerinaConf	Flag whether file is a ballerina config file	false

@docker:Expose{}

• Supported with ballerina listeners.

How to run

Prerequisites

1. Download and install JDK 11
2. Get a clone or download the source from this repository.
3. Export github personal access token & user name as environment variables.

       export packagePAT=<Token>
       export packageUser=<username>

4. (optional) Specify the Java home path for JDK 11 ie;

       export JAVA_HOME=/Library/Java/JavaVirtualMachines/adoptopenjdk-11.jdk/Contents/Home/

5. (optional) Ensure Docker daemon is running (used for building tests).

Building

1. Run the corresponding Gradle command from within the module-ballerina-docker directory.

#To build the module:
./gradlew clean build

#To build the module without the tests:
./gradlew clean build :docker-extension-test:prepareDistribution -x test

1. Copy docker-extension/build/docker-extension-***.jar file to <BALLERINA_HOME>/bre/lib directory.
2. Run bal build <.bal filename> to generate artifacts.

The docker artifacts will be created in a folder called docker with following structure.

|── docker
|    └── Dockerfile
└── outputfilename.jar

Enable building for Windows Platform

Use the "BAL_DOCKER_WINDOWS=true" environment variable to enable building docker images supporting Windows platform.

Enabling debug logs

Use the "BAL_DOCKER_DEBUG=true" environment variable to enable docker related debug logs when building the ballerina source file.

Annotation Usage Sample:

import ballerina/http;
import ballerina/log;
import ballerina/docker;

@docker:Expose{}
listener http:Listener helloWorldEP = new(9090);

@docker:Config {
    registry: "docker.abc.com",
    name: "helloworld",
    tag: "v1.0"
}
service http:Service /helloWorld on helloWorldEP {
    resource function get sayHello(http:Caller caller) {
        var responseResult = caller->respond("Hello, World! \n");
        if (responseResult is error) {
            log:printError("error responding back to client.", err = responseResult);
        }
    }
}

Refer samples for more info.