kubernetes/cmd/kubeadm/app/discovery/file/file.go

// RetrieveValidatedConfigInfo connects to the API Server and makes sure it can talk
// securely to the API Server using the provided CA cert and
// optionally refreshes the cluster-info information from the cluster-info ConfigMap
func RetrieveValidatedConfigInfo(filepath string, discoveryTimeout time.Duration) (*clientcmdapi.Config, error) { … }

// ValidateConfigInfo connects to the API Server and makes sure it can talk
// securely to the API Server using the provided CA cert/client certificates  and
// optionally refreshes the cluster-info information from the cluster-info ConfigMap
func ValidateConfigInfo(config *clientcmdapi.Config, discoveryTimeout time.Duration) (*clientcmdapi.Config, error) { … }

// tryParseClusterInfoFromConfigMap tries to parse a kubeconfig file from a ConfigMap key
func tryParseClusterInfoFromConfigMap(cm *v1.ConfigMap) (*clientcmdapi.Config, error) { … }