mongodb-docker: provide better error message when docker isn't available

[carolynvs]

I just ran porter list when docker wasn't running and the error message isn't really helpful. It would be great if the mongodb-docker plugin can detect that docker isn't responding and then tell people to start it.

porter list
2022-05-16T11:33:47.714-0500	error	could not configure a tracer: context deadline exceeded
2022-05-16T11:33:48.719-0500	error	could not configure a tracer: context deadline exceeded
2022-05-16T11:33:51.810-0500	error	rpc error: code = Unknown desc = error creating porter-mongodb-docker-plugin-data docker volume:
2022-05-16T11:33:51.810-0500	error	could not list installations: could not read storage schema document: rpc error: code = Unknown desc = error creating porter-mongodb-docker-plugin-data docker volume:

[joshuabezaleel]

Is this similar to #1926 ?

[carolynvs]

They are both user experience improvements but are detecting different error cases. This one is for when docker isn't running, and the mongodb-docker plugin should provide a better error message when docker isn't running. The other is for the mongodb storage plugin to check for common cases and provide a better message (for example when mongodb is down).

[joshuabezaleel]

Ah got it, thank you!

[github-actions]

Closed by #2217.