KEY:
identity_plugin  enable Identity Plugin via external hook

ARGS:
MINIO_IDENTITY_PLUGIN_URL*          (url)       plugin hook endpoint (HTTP(S)) e.g. "http://localhost:8181/path/to/endpoint"
MINIO_IDENTITY_PLUGIN_AUTH_TOKEN    (string)    authorization token for plugin hook endpoint
MINIO_IDENTITY_PLUGIN_ROLE_POLICY*  (string)    policies to apply for plugin authorized users

const (
	URL        = "url"
	AuthToken  = "auth_token"
	RolePolicy = "role_policy"
	RoleID     = "role_id"

	EnvIdentityPluginURL        = "MINIO_IDENTITY_PLUGIN_URL"
	EnvIdentityPluginAuthToken  = "MINIO_IDENTITY_PLUGIN_AUTH_TOKEN"
	EnvIdentityPluginRolePolicy = "MINIO_IDENTITY_PLUGIN_ROLE_POLICY"
	EnvIdentityPluginRoleID     = "MINIO_IDENTITY_PLUGIN_ROLE_ID"
)

var (
	// DefaultKVS - default config for AuthN plugin config