podNodeSelectorPluginConfig need validation when start

[mdshuai]

Kubernetes version (use kubectl version):
v1.5.0-alpha.1.857+c81816751387a2-dirty

How to reproduce it (as minimally and precisely as possible):

1. Start kube-apiserver with invalid value for PodNodeSelector admission controller
--admission-control=PodNodeSelector, --admission-control-config-file=admission-control-config-file.cfg

# cat ../admission-control-config-file.cfg
podNodeSelectorPluginConfig:
 clusterDefaultNodeSelector: region#=xyz%
 ns3: os=@#^&*,region=west^&*

2. Create a pod in this env
[root@ip-172-18-6-200 podnodeselector]# kc create -f https://raw.githubusercontent.com/mdshuai/testfile-openshift/master/k8s/pod/hello-pod.yaml
Error from server: error when creating "https://raw.githubusercontent.com/mdshuai/testfile-openshift/master/k8s/pod/hello-pod.yaml": invalid label key "region#": name part must match the regex ([A-Za-z0-9][-A-Za-z0-9_.]*)?[A-Za-z0-9] (e.g. 'MyName' or 'my.name' or '123-abc')

Expected results

1. Should start failed PodNodeSelector with invalid podNodeSelectorPluginConfig value.

Anything else do we need to know:

[mdshuai]

@aveshagarwal @derekwaynecarr

[aveshagarwal]

@derekwaynecarr I do not have enough permissions, could you assign this issue to me?

[aveshagarwal]

@mdshuai I verified the code and validation of default cluster wide selectors and whitelist happens when a pod is being admitted, not when the pluging config file is read.

[spiffxp]

/sig api-machinery

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