Refactor auth: add token and store implementations (#1230)

* Refactor auth: add token and memory implementations

* Fix typo

* Remove memory auth (implemented already by the store implementation), revert default to noop

* Add grpc header

* Global Config

* config/global => util/config

* Rename package to remove confict

* Tweak

* Improve Error Handling

auth/default.go

@@ -1,39 +1,36 @@
 package auth
 
 var (
-	DefaultAuth Auth = new(noop)
+	DefaultAuth = NewAuth()
 )
 
-type noop struct {
-	options Options
+// NewAuth returns a new default registry which is noop
+func NewAuth(opts ...Option) Auth {
+	return noop{}
 }
 
-// String name of implementation
-func (a *noop) String() string {
+type noop struct{}
+
+func (noop) Init(opts ...Option) error {
+	return nil
+}
+
+func (noop) Options() Options {
+	return Options{}
+}
+
+func (noop) Generate(id string, opts ...GenerateOption) (*Account, error) {
+	return nil, nil
+}
+
+func (noop) Revoke(token string) error {
+	return nil
+}
+
+func (noop) Validate(token string) (*Account, error) {
+	return nil, nil
+}
+
+func (noop) String() string {
 	return "noop"
 }
-
-// Init the svc
-func (a *noop) Init(...Option) error {
-	return nil
-}
-
-// Options set in init
-func (a *noop) Options() Options {
-	return a.options
-}
-
-// Generate a new auth Account
-func (a *noop) Generate(id string, ops ...GenerateOption) (*Account, error) {
-	return nil, nil
-}
-
-// Revoke an authorization Account
-func (a *noop) Revoke(token string) error {
-	return nil
-}
-
-// Validate a  account token
-func (a *noop) Validate(token string) (*Account, error) {
-	return nil, nil
-}