Test cases are also needed.

I have not find a k8s mock apiserver like one in the test case

is this what you are looking for? https://github.com/shreemaan-abhishek/apisix/blob/5319503293c41cf41a2caa5cb944a12d40686c83/t/kubernetes/discovery/kubernetes.t#L38-L97

@shreemaan-abhishek ，Thanks , I have found the method build k8s test env in workflows/kubernetes-ci.yml .

@hanqingwu should we add docs as well? Also, could you please show how the response body looks like?

yes, we should add docs
response like this:
{"endpoints":[{"id":"first","endpoints":[{"name":"default/kubernetes","value":"{\"https\":[{\"host\":\"172.18.0.2\",\"port\":6443,\"weight\":50}]}"},{"name":"kube-system/kube-dns","value":"{\"dns-tcp\":[{\"host\":\"10.244.0.3\",\"port\":53,\"weight\":50},{\"host\":\"10.244.0.4\",\"port\":53,\"weight\":50}],\"dns\":[{\"host\":\"10.244.0.3\",\"port\":53,\"weight\":50},{\"host\":\"10.244.0.4\",\"port\":53,\"weight\":50}],\"metrics\":[{\"host\":\"10.244.0.3\",\"port\":9153,\"weight\":50},{\"host\":\"10.244.0.4\",\"port\":9153,\"weight\":50}]}"},{"name":"local-path-storage/rancher.io-local-path","value":"{}"},{"name":"ns-a/ep","value":"{}"},{"name":"ns-b/ep","value":"{}"},{"name":"ns-c/ep","value":"{}"}]},{"id":"second","endpoints":[{"name":"default/kubernetes","value":"{\"https\":[{\"host\":\"172.18.0.2\",\"port\":6443,\"weight\":50}]}"},{"name":"kube-system/kube-dns","value":"{\"dns-tcp\":[{\"host\":\"10.244.0.3\",\"port\":53,\"weight\":50},{\"host\":\"10.244.0.4\",\"port\":53,\"weight\":50}],\"dns\":[{\"host\":\"10.244.0.3\",\"port\":53,\"weight\":50},{\"host\":\"10.244.0.4\",\"port\":53,\"weight\":50}],\"metrics\":[{\"host\":\"10.244.0.3\",\"port\":9153,\"weight\":50},{\"host\":\"10.244.0.4\",\"port\":9153,\"weight\":50}]}"},{"name":"local-path-storage/rancher.io-local-path","value":"{}"},{"name":"ns-a/ep","value":"{}"},{"name":"ns-b/ep","value":"{}"},{"name":"ns-c/ep","value":"{}"}]}],"config":[{"id":"first","client":{"token_file":"/tmp/var/run/secrets/kubernetes.io/serviceaccount/token"},"service":{"host":"127.0.0.1","schema":"https","port":"6443"},"watch_endpoint_slices":true,"default_weight":50,"shared_size":"1m"},{"id":"second","client":{"token_file":"/tmp/var/run/secrets/kubernetes.io/serviceaccount/token"},"service":{"host":"127.0.0.1","schema":"http","port":"6445"},"watch_endpoint_slices":true,"default_weight":50,"shared_size":"1m"}]}

Please add docs then.