Still deciding on API.

auth/api.go

@@ -23,6 +23,11 @@ type AuthenticatableUser interface {
 type AuthMixin struct {
 }
 
+type UserCodec interface {
+	Encode() ([]byte, error)
+	Decode([]byte) (BaseUser, error)
+}
+
 // CurrentUser loads and returns user data from the routing context. This will
 // examine session state whenever called.
 /*func CurrentUser(ctx *routing.Context) BaseUser {

auth/types.go

@@ -1,9 +1,14 @@
 package auth
 
 import (
+	"context"
 	"net/http"
+
+	"git.pluggableideas.com/destrealm/go/keystar/crypto"
 )
 
+type UserLoader func(id int) (BaseUser, error)
+
 type contextKey struct {
 	key string
 }
@@ -12,12 +17,50 @@ func (k *contextKey) String() string {
 	return "Capstan authentication key:" + k.key
 }
 
+var authContextKey = &contextKey{"authentication"}
+
 type AuthenticatorMiddleware struct {
 	// FailController indicates which controller should be used as the
 	// redirection target if the user's authentication fails. FailController
 	// string FailURL url.URL
+
+	CookieName string
+
+	Codec UserCodec
+
+	UserLoader UserLoader
+
+	sealer crypto.Sealer
 }
 
-func (m *AuthenticatorMiddleware) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+func (m *AuthenticatorMiddleware) Middleware() func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		fn := func(w http.ResponseWriter, r *http.Request) {
+			cookie, err := r.Cookie(m.CookieName)
+			if err != nil {
+				return
+			}
+
+			user, err := m.Codec.Decode([]byte(cookie.Value))
+			if err != nil {
+				return
+			}
+
+			// UserLoader may return the same user instance or it may return a
+			// new instance that implements the BaseUser interface. The latter
+			// method allows for later casting to a different interface or type
+			// whenever more application-specific data is needed.
+			user, err = m.UserLoader(user.ID())
+			if err != nil {
+				return
+			}
+
+			r = r.WithContext(context.WithValue(r.Context(), authContextKey, user))
+			next.ServeHTTP(w, r)
+		}
+		return http.HandlerFunc(fn)
+	}
+}
 
-}
+// Attach to request context?
+//func WriteCookie()