support CAS identity provider

Signed-off-by: hongming <talonwan@yunify.com>

vendor/gopkg.in/cas.v2/ticket_store.go

@@ -0,0 +1,27 @@
+package cas
+
+import (
+	"errors"
+)
+
+// TicketStore errors
+var (
+	// Given Ticket is not associated with an AuthenticationResponse
+	ErrInvalidTicket = errors.New("cas: ticket store: invalid ticket")
+)
+
+// TicketStore provides an interface for storing and retrieving service
+// ticket data.
+type TicketStore interface {
+	// Read returns the AuthenticationResponse data associated with a ticket identifier.
+	Read(id string) (*AuthenticationResponse, error)
+
+	// Write stores the AuthenticationResponse data received from a ticket validation.
+	Write(id string, ticket *AuthenticationResponse) error
+
+	// Delete removes the AuthenticationResponse data associated with a ticket identifier.
+	Delete(id string) error
+
+	// Clear removes all of the AuthenticationResponse data from the store.
+	Clear() error
+}