Test dockerized app files

[Nekroze]

Change Request

Please describe the current behaviour

At present dab only tests apps by starting a select few.

What is suboptimal about the current behaviour

The current behaviour is insufficient because apps may be broken in easy to detect ways in a merge without knowing.

Describe the way you think it should behave

Run docker-compose build -f docker-compose.*.yml in its own parallel test job that would fail if any Dockerfile or docker-compose.yml is invalid/malformed.

[Nekroze]

Testing by creating all services takes far too long in CI. Perhaps look at some linting to check validity.

[tommymcguiver]

Can validate config like so
[kenm@gijoevm020 docker]$ docker-compose -f docker-compose.vault.yml config -q
echoERROR: Service 'vault' depends on service 'consul' which is undefined.

[Nekroze]

@tommymcguiver good idea! we could use dab apps config which does the dependency lookup and will error if the yaml is an invalid docker-compose schema... Doesn't ensure the apps function as intended but this would be an improvement.