--mount flag in update command failed with more than one level of directory

[zsxking]

Bug report

When trying to mount a configmap with:

$ kn service update heloapp -n app --mount /my/path=cm:test

it gives error

Error: giving up after 3 retries: admission webhook "validation.webhook.serving.knative.dev" denied the request: validation failed: invalid value: my.path-1f5d5125: spec.template.spec.volumes[1].name

Expected behavior

It should work and mount the configmap onto /my/path

When mounting to folder on root, like /mypath, it work:

$ kn service update heloapp -n app --mount /mypath=cm:test
Updating Service 'heloapp' in namespace 'app':
...

Steps to reproduce the problem

1. create a configmap called test
2. deploy a kn service: kn service create hello --image gcr.io/cloudrun/hello
3. use kn service update to mount the configmap to mypath: kn service update hello --mount /my/path=cm:test

kn version

Version:      v20200728-4c246812
Build Date:   2020-07-28 10:36:25
Git Revision: 4c246812
Supported APIs:
* Serving
  - serving.knative.dev/v1 (knative-serving v0.16.1-0.20200715073232-81d40bfc82a6)
* Eventing
  - sources.knative.dev/v1alpha2 (knative-eventing v0.16.1-0.20200715062032-28f9f61e6131)
  - eventing.knative.dev/v1beta1 (knative-eventing v0.16.1-0.20200715062032-28f9f61e6131)

Knative (serving/eventing) version

0.13.2

[navidshaikh]

The volume spec requires the volume to be DNS_LABEL, which only allows - in the names. We are currently replacing all the / with . (except root /).

[navidshaikh]

/assign