Do away with non-bang #create_XXX methods?

[krallin]

The current #create_XXX methods (e.g. app.create_operation) swallow errors, and return a Aptible::Resource::Base object, which can be very confusing, especially considering that attempting to reload those resources will throw an immensely cryptic Resource server root URL must be defined by subclass error.

Now, we do have equivalent bang methods (e.g. app.create_operation!), which do throw exception, but they're not used everywhere.

For example, in aptible-integration, we're using app.create_operation practically everywhere), and when it started throwing Resource server root URL must be defined by subclass (https://travis-ci.com/aptible/aptible-integration/jobs/41749266), it wasn't immediately obvious at all that the cause was in API (ultimately https://github.com/aptible/api.aptible.com/pull/373).

Is there value in having methods that swallow errors? Is there value in that being the most natural method call? I think the answer to both questions is no, and I think we should simply make both methods do the same thing (i.e. raise exceptions), and possibly raise a deprecation warning on the bang methods that they're now redundant.

Thoughts @blakepettersson @fancyremarker?

[fancyremarker]

I'm fine with this. The existing behavior is intended to provide some similarity to the ActiveRecord API, but the issues you point out are reason enough not to support non-bang methods.