skeleton_syncservice

Java skeleton for a synchronous service

This is a bare-bone skeleton of a Java synchronous-service application, wrapped in a Docker container containig a Glassfish 5.0 Java application server.

Prerequisites

To build, run, and test this skeleton service, you only need to have Docker installed on your machine. All required software is already bundled in Docker containers.

For further development based on this skeleton, it is highly recommended to use a Java IDE such as Netbeans.

Build, configure, and run the service

Build

To compile service skeleton's source code and pack it into a Docker container, run

./build.sh

This will trigger a Java maven Docker container which compiles the source code. On the first run, this will take a while, since first the container has to be downloaded and then all necessary Java dependencies need to be installed. Afterwards, build times will be reduced tremendously.

Afterwards, docker is called to build an image out of the compiled source code.

Configuration

Prior to running the service, have a look at env_template. This file defines environment variables which will be passed into the container. The first one, CONTEXT_ROOT, defines the deployment path of the app relative to root. This service defines the webservice SyncExample and has a default configuration of CONTEXT_ROOT=/sintef/examples/syncservice. This means that the web service will later be reachable under <hostname>/sintef/examples/syncservice/SyncExample?wsdl.

The rest of the file contains further configuration variables which will can be used in the application source code.

Running

To run the container locally, simply execute

./run.sh

Alternatively, run

docker run -p 8080:8080 --env-file=env_template skeleton_syncservice

Testing the service

Once the container is running, it can be tested by using its published wsdl file to create a SOAP webclient and call methods with it.

This example includes a Python-based client application, found in the test_client/ folder. If you have a local Python 3.x environment, you can simply run python test_service.py (make sure that all dependencies defined in requirements.txt) are installed. Alternatively, the example includes a Python Docker container for executing the test client.

To use the Python container, run

cd test_client
./build.sh      # run only once
./run.sh

You can make changes to test_service.py to test other methods or other deployment locations. Rebuilding the container is not necessary after such changes.

Use this skeleton as a template

When using this skeleton as a code template for other services, please make sure to follow the instructions for renaming the service found in the Java source code.

Afterwards, also edit Dockerfile and update the name of the .war compiled package accordingly.

Modifying the Glassfish application server

The Glassfish application server is pre-configured to run without problems in any deployment environment. Should you need to modify its configuration, edit the entrypoint script docker_entrypoint.sh and rebuild the container.

Note that by default, Glassfish's admin-console port 4848 is not exposed. If you need access to the admin console, edit Dockerfile accordingly, run the container with an additional -p 4848:4848 port mapping, and grab the admin password from the container startup log.