This is a very simple demo application that is used to show a web client applicatoin and a Java application executing in Docker containers. We also include a simple load testing container.

The application is very simple, a web client application communicates with a Java REST API and returns the information to the user.

This is not a real application. It doesn't do anything useful and it isn't intended to do so. Neither is it a demonstration of best practice application management. It is merely an introduction to using containerized applications on Microsoft Azure.

See the docs folder for some getting started guides and a tutorial deck that includes the essentials. If you are new to Docker then you probably want to start there.

There are a few things you need to do to setup your environment, such as installing docker clients and creating host machines on which to deploy your containers. Take a look at the file environmentSetup.md and come back here when you are done.

The application is best run with Docker Compose:

docker-compose up -d

You can scale the web application up or down too:

docker-compose scale web=3

The /script directory contains a number of helper scripts for managing our build and development environments. Generally for starting up the application you should use Docker-Compose, the scripts in this directory are deprecated, there are, however, still useful for people learning about Docker and how it works because Docker Compose hides some details whereas the scripts show exactly what is happening.

Copy /scripts/config.tmpl to scripts/config.sh before using these scripts. You might want to edit scripts/config.sh, see the file for details.

The top level scripts, dev.sh and stage.sh, are the best place to start, the first will deploy and load test the application on your dev host while the second will deploy and load test the application on the staging server.

We use an HA Proxy load balancer which dynamically discovers instances of the web application running on the same host.

This is about as simple as a web application gets.

This is a simple PHP application. That makes a call to the REST API (see below) and provides a response. We start two instances of this application and use a HAProxy load balancer to handle requests.

Based on http://javahash.com/jersey-hello-world-example/

While it might seem strange to load test a Hello World application we've included a container that does just that!

The loadTest container will run a set of tests against the web application each time it is staged. To view the log output once the execution has completed run the command:

docker logs stage_load