Familiar Sight for Developers

The aspects of OpenShift I have looked at so far mostly relate to the installation and operation of clusters, as well as the containers within. However, OpenShift is not an operations tool: DevOps is its hunting ground, and developers will find plenty of attractive features in the solution.

In the context of OpenShift, DevOps means that the platform does not just start gears and groups of gears with specific environments and services on request: It is additionally in a position to roll out applications automatically. The application is a distinct administrative unit in OpenShift, and gears are consolidated into logical groups that bear the name of the application.

A Git server belongs directly to OpenShift: Developers create an application in OpenShift and select which features it has (e.g., "needs MySQL" and "uses PHP"). Afterward, they can check out the (empty) Git directory locally that pertains to this application and make their changes. All aspects of this application can be configured via the Git directory. Once the local changes are complete, one executes a commit via Git and a final push back to OpenShift. This ensures that in the final step, the Git folder's changes are activated in the container.

One indispensable tool for continuous development is Jenkins, which puts new code through its paces by checking it with a myriad of previously confirmed test cases. Those who do not want to push their changes directly from development into a container can run them through the tests defined in Jenkins for reinforcement before the code is rolled out in a container.

If you want another tool for code checking besides Jenkins, you can use hooks (see Figure 5) that let you specify actions directly in the Git directory, which OpenShift will then execute after a change to the application.

Figure 5: With the help of hooks, actions can be started before building containers, during the process, or before and during deployment.

Conclusion

OpenShift impresses with its solid functionality and simplicity. The product achieves what the manufacturer promises: If you want PaaS, you will definitely make your daily routine easier with the use of OpenShift. OpenShift has a clear advantage over pure Kubernetes; complete and even supplier-certified containers for specific environments are especially important in this regard.

However, the product is also very attractive because it integrates well with development processes and considerably shortens the route that the source code takes from developer to final roll-out into production. If you have already thought about using Kubernetes in your own company, by all means take a closer look at OpenShift.