I have looked at the documentation of fabric8 but I did not found answers for these questions: 1. How external resources like RDBMS/Nosql/Middelwares used by a microservice app should be installed for the different stages : I guess that using a docker-compose file referencing the docker images for a db for example is not sufficient or should it be manually.
An example of an app microservice using an external resources would be very helpful.
If you refer to the fabric8-maven-plugin for creating Kubernetes and OpenShift resource descriptors, you can specify so called resource fragments in the src/main/fabric8 which refers your external services and which will be picked up with mvn fabric8:resource.
The GitHub organisation https://github.com/fabric8-quickstarts contains a lot of examples, unfortunately not one which directly picks up an external service.
Another source of examples is https://github.com/fabric8io/fabric8-devops which contains tons of external application packaged with fabric8-maven-plugin (e.g. fluentd).
The documentation also contains a section on resource fragments which you can put in src/main/fabric8