Expose binding-apiserver directly to end uses

[huiwq1990]

What would you like to be added?

1）Export binding-apiserver as apiserver directly to user, the server path not need add lusterpedia.io/v1beta1/resources suffix； 2）clusterpedia-apiserver support service nodeport;

In a word, we want to use binding-apiserver like this:

apiVersion: v1
kind: Config
clusters:
- name: default-cluster
  cluster:
    insecure-skip-tls-verify: true
    server: https://${binding-apiserve-ip}:${binding-apiserve-port}
contexts:
- name: default-context
  context:
    cluster: default-cluster
    namespace: default
    user: default-user
current-context: default-context
users:
- name: default-user
  user:
    token:  abc

The binding-apiserve-ip could be clusterpedia-apiserver service ip or host cluster node ip. The binding-apiserve-port could be clusterpedia-apiserver service port or nodeport.

Why is this needed?

In normal case, binding-apiserver works as a aggregated apiserver, and exposed by host apiserver. So all binding-apiserver requests must forward by host apiserver, and it effects host apiserver performance. In other case, we want to watch binding-apiserver, but after a while, we get some error.

I1109 09:23:51.743143       1 httplog.go:131] "HTTP" verb="GET" URI="/apis/clusterpedia.io/v1beta1/resources/api/v1/nodes?limit=500" latency="7.3116ms" userAgent="kubectl/v1.16.15 (linux/amd64) kubernetes/2adc8d7" audit-ID="4132ae59-b216-485f-8a83-2caa0d5c6085" srcIP="10.0.0.4:47654" apf_pl="workload-low" apf_fs="service-accounts" apf_iseats=1 apf_fseats=0 apf_additionalLatency="0s" apf_execution_time="7.111772ms" resp=200
I1109 09:24:21.745886       1 panic.go:884] "HTTP" verb="WATCH" URI="/apis/clusterpedia.io/v1beta1/resources/api/v1/nodes?resourceVersion=eyJlZGdlLWNsdXN0ZXItMDEiOiIxNTY1NTQ2MTcifQ&watch=true" latency="30.000275432s" userAgent="kubectl/v1.16.15 (linux/amd64) kubernetes/2adc8d7" audit-ID="61dbd476-1c2b-4191-983e-4a8ee928906c" srcIP="10.0.0.4:47654" apf_pl="workload-low" apf_fs="service-accounts" apf_iseats=1 apf_fseats=0 apf_additionalLatency="0s" resp=200
E1109 09:24:21.745986       1 wrap.go:53] timeout or abort while handling: method=GET URI="/apis/clusterpedia.io/v1beta1/resources/api/v1/nodes?resourceVersion=eyJlZGdlLWNsdXN0ZXItMDEiOiIxNTY1NTQ2MTcifQ&watch=true" audit-ID="61dbd476-1c2b-4191-983e-4a8ee928906c"
E1109 09:24:21.746163       1 timeout.go:141] post-timeout activity - time-elapsed: 260.416µs, GET "/apis/clusterpedia.io/v1beta1/resources/api/v1/nodes" result: net/http: abort Handler

[clusterpedia-bot]

Hi @huiwq1990, Thanks for opening an issue! We will look into it as soon as possible.

Details

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[Iceber]

The apiserver can open the NodePort directly to provide external access, or you can access the clusterpedia apiserver service directly in the cluster.

Of course, you still need to add a prefix clusterpedia.io/v1beta1/resources

Adding paths without prefixes looks good, and in the future we might be able to add a gate to support it