Thermostat + Wildfly Builder Image for OpenShift

This repository contains a sample Dockerfile for a builder image which can be used as a drop-in replacement of the openshift/wildfly-101-centos7 image.

The difference between openshift/wildfly-101-centos7 and this image is that the result will be capable of optionally starting a Thermostat agent within a deployment.

See Thermostat on OpenShift Usage for more details as to how to use the built image.

Usage

In order to build the Wildfly Builder image on a properly subscribed RHEL machine execute the following:

$ docker build -f Dockerfile.rhel7 -t thermostat/wildfly-101-rhel7 .

The resulting image can then be used to build your Wildfly app:

$ s2i build file://$(pwd)/test/wildfly-testapp thermostat/wildfly-101-rhel7 wildfly-testapp

Then run the app as usual:

$ docker run -p 8080:8080 -d wildfly-testapp

Enabling the Thermostat Agent

In order to enable the Thermostat Agent for an app image certain environment variables need to be set and a storage endpoint needs to be running for the Thermostat Agent to connect to.

Starting the Thermostat Storage Endpoint

We can use the rhscl/thermostat-16-storage-rhel7 image for this. That image in turn relies on a third image, rhscl/mongodb-32-rhel7 for example, for its mongodb backend.

Let's start the mongodb image first:

$ MONGO_CID=$(mktemp -u --suffix=.cid)
$ docker run -d \
          -e MONGODB_USER=mongouser \
          -e MONGODB_PASSWORD=mongopassword \
          -e MONGODB_DATABASE=thermostat \
          -e MONGODB_ADMIN_PASSWORD=changeme123 \
          --cidfile=${MONGO_CID} \
          rhscl/mongodb-32-rhel7
$ MONGO_IP=$( docker inspect --format '{{ .NetworkSettings.IPAddress }}' $(cat ${MONGO_CID}) )

Now start the Thermostat Storage Endpoint:

$ TH_STORAGE_CID=$(mktemp -u --suffix=.cid)
$ docker run -p 8081:8080 -d \
          -e MONGO_URL=mongodb://${MONGO_IP}:27017 \
          -e MONGO_USERNAME=mongouser \
          -e MONGO_PASSWORD=mongopassword \
          -e THERMOSTAT_AGENT_USERNAMES="agent1" \
          -e THERMOSTAT_AGENT_PASSWORDS="a_secrit1" \
          -e THERMOSTAT_CLIENT_USERNAMES="client1" \
          -e THERMOSTAT_CLIENT_PASSWORDS="c_secrit1" \
          --cidfile=${TH_STORAGE_CID} \
          rhscl/thermostat-16-storage-rhel7
$ TH_STORAGE_IP=$( docker inspect --format '{{ .NetworkSettings.IPAddress }}' $(cat ${TH_STORAGE_CID}) )

Start the Application with the Thermostat Agent

In the above wildfly-testapp application case this could be done as follows:

$ docker run -p 8080:8080 -p 12000:12000 \
   -e THERMOSTAT_AGENT_USERNAME=agent1 \
   -e THERMOSTAT_AGENT_PASSWORD=a_secrit1 \
   -e THERMOSTAT_DB_URL=http://${TH_STORAGE_IP}:8080/thermostat/storage \
   -d wildfly-testapp

Disabling the Thermostat Agent

For a re-deployment of your application without a Thermostat Agent running unsetting one of the 3 THERMOSTAT_* environment variables is sufficient.