Use a distinct IterableCtxStore interface

data.go

@@ -653,7 +653,7 @@ func (s *SessionManager) doStoreCommit(ctx context.Context, token string, b []by
 }
 
 func (s *SessionManager) doStoreAll(ctx context.Context) (map[string][]byte, error) {
-	cs, ok := s.Store.(CtxStore)
+	cs, ok := s.Store.(IterableCtxStore)
 	if ok {
 		return cs.AllCtx(ctx)
 	}

store.go

@@ -39,15 +39,20 @@ type IterableStore interface {
 type CtxStore interface {
 	Store
 
-	// DeleteCtx same as Store.Delete, except it takes a context.Context.
+	// DeleteCtx is the same as Store.Delete, except it takes a context.Context.
 	DeleteCtx(ctx context.Context, token string) (err error)
 
-	// FindCtx same as Store.Find, except it takes a context.Context.
+	// FindCtx is thesame as Store.Find, except it takes a context.Context.
 	FindCtx(ctx context.Context, token string) (b []byte, found bool, err error)
 
-	// CommitCtx same as Store.Commit, except it takes a context.Context.
+	// CommitCtx is the same as Store.Commit, except it takes a context.Context.
 	CommitCtx(ctx context.Context, token string, b []byte, expiry time.Time) (err error)
+}
 
-	// AllCtx same as IterableStore.All, expect it takes a context.Context.
+// IterableCtxStore is the interface for session stores which support iteration
+// and which take a context.Context parameter.
+type IterableCtxStore interface {
+	// AllCtx is the same as IterableStore.All, expect it takes a
+	// context.Context.
 	AllCtx(ctx context.Context) (map[string][]byte, error)
 }