Make allowed kubectl commands configurable

[girishg4t]

ISSUE TYPE

• Feature Pull Request

SUMMARY

Added configuration in resource_config.yaml for limiting kubectl commands as per the discussion given in ticket 183

The configuration added is used in
slack.go and mattermost.go to pass it to executor.go and used to limit the commands execution

Fixes #183

[PrasadG193]

@girishg4t could you please resolve the errors in CI build?

[girishg4t]

@PrasadG193 fixed the issue in test case

[PrasadG193]

extra leading space?

Suggested change

	# List of allowed commands
	# List of allowed commands

[PrasadG193]

Suggested change

	verbs: ["api-resources","api-versions","cluster-info","describe","diff","explain","get","logs","top","auth"]
	verbs: ["api-resources", "api-versions", "cluster-info", "describe", "diff", "explain", "get", "logs", "top", "auth"]

[PrasadG193]

@girishg4t We should also allow if someone uses singular resource name - like @BotKube get pod

[girishg4t]

@PrasadG193 i have made the changes as per review comments please check

[PrasadG193]

@girishg4t This is yet to be resolved #284 (comment)

[girishg4t]

@girishg4t This is yet to be resolved #284 (comment)

@PrasadG193 is this not the one ?
af7dd4e

[PrasadG193]

If user configured access with -

    commands:
      # method which are allowed
      verbs: ["get"]
      # resource configuration which is allowed
      resources: ["deployments"]

Will they be able to execute @BotKube get deploy or @BotKube get deployment. I don't think so.
I think what we should do is, we should execute kubectl api-resources (which include singular name as well as short name for the resources https://godoc.org/k8s.io/apimachinery/pkg/apis/meta/v1#APIResource) during init() and store the response. Then for every user's command, get resources name from shortname if passed from that list. We can use Discovery APIs to get the resource list - https://godoc.org/k8s.io/client-go/discovery#ServerGroupsAndResources

[PrasadG193]

@girishg4t [minor] ideally PR heading should be one-liner summary of what you have done. It should inform reader what is the PR about. Please follow this while creating PR next time 🙂

[PrasadG193]

@girishg4t I've done a few changes as per the discussion. Going to merge once CI passes. PTAL