[v2][non-kube] site create command and CLI adaptation

[nluaces]

• Kube and non-kube implementations are available with the --platform at execution level to avoid dependency on the generic configuration only (through environment variables).
• In non-kube platforms, the custom resources will be stored on a path provided by the component PathProvider. If the user does not provide a namespace (with --namespace), they will be created in the default namespace.

[lynnemorrison]

The code looks really good!!

[nluaces]

A few highlights that may be helpful to review this pull request:

• Refactor: the cobra command is defined outside the implementation of the different platforms, one cobra command will have available 2 implementations (kube and nonkube) to have both of them available at execution time. This change implied the modification of the test suites.

• Nonkube command implementation: There is only one nonkube command implemented, and it is the skupper site create command, the rest will be implemented on following pull requests

• New package fs (filesystem):

  • PathProvider: determines the path where the custom resource files should be located, .local/share/skupper/default/prepared/state by default.
  • CustomResourceHandler: this is the interface that will implement the rest of the handlers defined for each custom resource. For example, SiteHandler implements CustomResourceHandler interface and writes and stores the file in the correct directory (.local/share/skupper/default/prepared/state/sites)

That way the skupper command is decoupled from the logic of managing custom resources in a nonkube way.

[ajssmith]

built and used against kind cluster various cli operations

lgtm

[c-kruse]

🥳

[nluaces]

@fgiorgetti let me know if something is missing before I merge this pull request. Thanks!

[fgiorgetti]

@fgiorgetti let me know if something is missing before I merge this pull request. Thanks!

Thank you very much @nluaces for addressing all the comments.