// DefaultClientConfig creates a clientcmd.ClientConfig with the following hierarchy:
// 1. Use the kubeconfig builder. The number of merges and overrides here gets a little crazy. Stay with me.
// 1. Merge together the kubeconfig itself. This is done with the following hierarchy rules:
// 1. CommandLineLocation - this parsed from the command line, so it must be late bound. If you specify this,
// then no other kubeconfig files are merged. This file must exist.
// 2. If $KUBECONFIG is set, then it is treated as a list of files that should be merged.
// 3. HomeDirectoryLocation
// Empty filenames are ignored. Files with non-deserializable content produced errors.
// The first file to set a particular value or map key wins and the value or map key is never changed.
// This means that the first file to set CurrentContext will have its context preserved. It also means
// that if two files specify a "red-user", only values from the first file's red-user are used. Even
// non-conflicting entries from the second file's "red-user" are discarded.
// 2. Determine the context to use based on the first hit in this chain
// 1. command line argument - again, parsed from the command line, so it must be late bound
// 2. CurrentContext from the merged kubeconfig file
// 3. Empty is allowed at this stage
// 3. Determine the cluster info and auth info to use. At this point, we may or may not have a context. They
// are built based on the first hit in this chain. (run it twice, once for auth, once for cluster)
// 1. command line argument
// 2. If context is present, then use the context value
// 3. Empty is allowed
// 4. Determine the actual cluster info to use. At this point, we may or may not have a cluster info. Build
// each piece of the cluster info based on the chain:
// 1. command line argument
// 2. If cluster info is present and a value for the attribute is present, use it.
// 3. If you don't have a server location, bail.
// 5. Auth info is build using the same rules as cluster info, EXCEPT that you can only have one authentication
// technique per auth info. The following conditions result in an error:
// 1. If there are two conflicting techniques specified from the command line, fail.
// 2. If the command line does not specify one, and the auth info has conflicting techniques, fail.
// 3. If the command line specifies one and the auth info specifies another, honor the command line technique.
// 2. Use default values and potentially prompt for auth information
//
// However, if it appears that we're running in a kubernetes cluster
// container environment, then run with the auth info kubernetes mounted for
// us. Specifically:
// The env vars KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT are
// set, and the file /var/run/secrets/kubernetes.io/serviceaccount/token
// exists and is not a directory.
func DefaultClientConfig(flags *pflag.FlagSet) clientcmd.ClientConfig {
loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
flags.StringVar(&loadingRules.ExplicitPath, "kubeconfig", "", "Path to the kubeconfig file to use for CLI requests.")
overrides := &clientcmd.ConfigOverrides{}
flagNames := clientcmd.RecommendedConfigOverrideFlags("")
// short flagnames are disabled by default. These are here for compatibility with existing scripts
flagNames.ClusterOverrideFlags.APIServer.ShortName = "s"
clientcmd.BindOverrideFlags(overrides, flags, flagNames)
clientConfig := clientcmd.NewInteractiveDeferredLoadingClientConfig(loadingRules, overrides, os.Stdin)
return clientConfig
}
func NewDefaultPathOptions() *PathOptions {
ret := &PathOptions{
GlobalFile: clientcmd.RecommendedHomeFile,
EnvVar: clientcmd.RecommendedConfigPathEnvVar,
ExplicitFileFlag: clientcmd.RecommendedConfigPathFlag,
GlobalFileSubpath: path.Join(clientcmd.RecommendedHomeDir, clientcmd.RecommendedFileName),
LoadingRules: clientcmd.NewDefaultClientConfigLoadingRules(),
}
ret.LoadingRules.DoNotResolvePaths = true
return ret
}