Make HTTP middleware easier to use

server/auth/context_test.go

 // Copyright 2015 The LUCI Authors. All rights reserved.
 // Use of this source code is governed under the Apache License, Version 2.0
 // that can be found in the LICENSE file.
 
 package auth
 
 import (
         "fmt"
         "net/http"
         "net/http/httptest"
         "net/url"
         "testing"
 
-        "github.com/julienschmidt/httprouter"
         "golang.org/x/net/context"
 
         "github.com/luci/luci-go/common/errors"
         "github.com/luci/luci-go/server/auth/identity"
-        "github.com/luci/luci-go/server/middleware"
+        "github.com/luci/luci-go/server/router"
         . "github.com/smartystreets/goconvey/convey"
 )
 
 func TestContext(t *testing.T) {
         Convey("Works", t, func() {
                 c := context.Background()
 
                 So(GetAuthenticator(c), ShouldBeNil)
                 _, err := LoginURL(c, "dest")
                 So(err, ShouldEqual, ErrNoUsersAPI)
@@ skipping 17 matching lines @@
                 So(err, ShouldBeNil)
                 So(dest, ShouldEqual, "http://login_url?r=dest")
                 dest, err = LogoutURL(c, "dest")
                 So(err, ShouldBeNil)
                 So(dest, ShouldEqual, "http://logout_url?r=dest")
         })
 
 }
 
 func TestContextAuthenticate(t *testing.T) {
-        call := func(c context.Context, h middleware.Handler) *httptest.ResponseRecorder {
+        call := func(c context.Context, handlers ...router.Handler) *httptest.ResponseRecorder {
                 req, err := http.NewRequest("GET", "http://example.com/foo", nil)
                 So(err, ShouldBeNil)
                 w := httptest.NewRecorder()
-                h(c, w, req, nil)
+                initializer := []router.Handler{func(ctx *router.Context) {
+                        ctx.Context = c
+                        ctx.Writer = w
+                        ctx.Request = req
+                }}
+                router.ChainHandlers(append(initializer, handlers...)...)()
                 return w
         }
 
-        handler := func(c context.Context, rw http.ResponseWriter, r *http.Request, p httprouter.Params) {
-                fmt.Fprintf(rw, "%s", CurrentIdentity(c))
+        handler := func(c *router.Context) {
+                fmt.Fprintf(c.Writer, "%s", CurrentIdentity(c.Context))
         }
 
         Convey("Not configured", t, func() {
-                rr := call(context.Background(), Authenticate(handler))
+                rr := call(context.Background(), Authenticate(), handler)
                 So(rr.Code, ShouldEqual, 500)
                 So(rr.Body.String(), ShouldEqual, "Authentication middleware is not configured\n")
         })
 
         Convey("Transient error", t, func() {
                 c := prepareCtx(fakeMethod{authError: errors.WrapTransient(errors.New("boo"))})
-                rr := call(c, Authenticate(handler))
+                rr := call(c, Authenticate(), handler)
                 So(rr.Code, ShouldEqual, 500)
                 So(rr.Body.String(), ShouldEqual, "Transient error during authentication - boo\n")
         })
 
         Convey("Fatal error", t, func() {
                 c := prepareCtx(fakeMethod{authError: errors.New("boo")})
-                rr := call(c, Authenticate(handler))
+                rr := call(c, Authenticate(), handler)
                 So(rr.Code, ShouldEqual, 401)
                 So(rr.Body.String(), ShouldEqual, "Authentication error - boo\n")
         })
 
         Convey("Works", t, func() {
                 c := prepareCtx(fakeMethod{userID: "user:abc@example.com"})
-                rr := call(c, Authenticate(handler))
+                rr := call(c, Authenticate(), handler)
                 So(rr.Code, ShouldEqual, 200)
                 So(rr.Body.String(), ShouldEqual, "user:abc@example.com")
         })
 
         Convey("Anonymous works", t, func() {
                 c := prepareCtx(fakeMethod{anon: true})
-                rr := call(c, Authenticate(handler))
+                rr := call(c, Authenticate(), handler)
                 So(rr.Code, ShouldEqual, 200)
                 So(rr.Body.String(), ShouldEqual, "anonymous:anonymous")
         })
 
         Convey("Broken ID is rejected", t, func() {
                 c := prepareCtx(fakeMethod{userID: "???"})
-                rr := call(c, Authenticate(handler))
+                rr := call(c, Authenticate(), handler)
                 So(rr.Code, ShouldEqual, 401)
                 So(rr.Body.String(), ShouldEqual, "Authentication error - auth: bad identity string \"???\"\n")
         })
 }
 
 func TestAutologin(t *testing.T) {
-        call := func(c context.Context, h middleware.Handler) *httptest.ResponseRecorder {
+        call := func(c context.Context, handlers ...router.Handler) *httptest.ResponseRecorder {
                 req, err := http.NewRequest("GET", "http://example.com/foo", nil)
                 So(err, ShouldBeNil)
                 w := httptest.NewRecorder()
-                h(c, w, req, nil)
+                initializer := []router.Handler{func(ctx *router.Context) {
+                        ctx.Context = c
+                        ctx.Writer = w
+                        ctx.Request = req
+                }}
+                router.ChainHandlers(append(initializer, handlers...)...)()
                 return w
         }
 
-        handler := func(c context.Context, rw http.ResponseWriter, r *http.Request, p httprouter.Params) {
-                fmt.Fprintf(rw, "%s", CurrentIdentity(c))
+        handler := func(c *router.Context) {
+                fmt.Fprintf(c.Writer, "%s", CurrentIdentity(c.Context))
         }
 
         Convey("Not configured", t, func() {
-                rr := call(context.Background(), Autologin(handler))
+                rr := call(context.Background(), Autologin(), handler)
                 So(rr.Code, ShouldEqual, 500)
                 So(rr.Body.String(), ShouldEqual, "Authentication middleware is not configured\n")
         })
 
         Convey("Transient error", t, func() {
                 c := prepareCtx(fakeMethod{authError: errors.WrapTransient(errors.New("boo"))})
-                rr := call(c, Autologin(handler))
+                rr := call(c, Autologin(), handler)
                 So(rr.Code, ShouldEqual, 500)
                 So(rr.Body.String(), ShouldEqual, "Transient error during authentication - boo\n")
         })
 
         Convey("Fatal error", t, func() {
                 c := prepareCtx(fakeMethod{authError: errors.New("boo")})
-                rr := call(c, Autologin(handler))
+                rr := call(c, Autologin(), handler)
                 So(rr.Code, ShouldEqual, 401)
         })
 
         Convey("Anonymous is redirected to login if has UsersAPI", t, func() {
                 c := prepareCtx(fakeMethod{anon: true})
-                rr := call(c, Autologin(handler))
+                rr := call(c, Autologin(), handler)
                 So(rr.Code, ShouldEqual, 302)
                 So(rr.Header().Get("Location"), ShouldEqual, "http://login_url?r=%2Ffoo")
         })
 
         Convey("Anonymous is rejected if no UsersAPI", t, func() {
                 c := prepareCtx(noUserAPI{})
-                rr := call(c, Autologin(handler))
+                rr := call(c, Autologin(), handler)
                 So(rr.Code, ShouldEqual, 401)
                 So(rr.Body.String(), ShouldEqual, "Authentication error - auth: methods do not support login or logout URL\n")
         })
 
         Convey("Handles transient error in LoginURL", t, func() {
                 c := prepareCtx(fakeMethod{anon: true, loginURLError: errors.WrapTransient(errors.New("boo"))})
-                rr := call(c, Autologin(handler))
+                rr := call(c, Autologin(), handler)
                 So(rr.Code, ShouldEqual, 500)
                 So(rr.Body.String(), ShouldEqual, "Transient error during authentication - boo\n")
         })
 
         Convey("Passes authenticated user through", t, func() {
                 c := prepareCtx(fakeMethod{userID: "user:abc@example.com"})
-                rr := call(c, Autologin(handler))
+                rr := call(c, Autologin(), handler)
                 So(rr.Code, ShouldEqual, 200)
                 So(rr.Body.String(), ShouldEqual, "user:abc@example.com")
         })
 }
 
 func prepareCtx(m ...Method) context.Context {
         c := SetAuthenticator(context.Background(), Authenticator(m))
         c = UseDB(c, func(context.Context) (DB, error) {
                 return &fakeDB{}, nil
         })
@@ skipping 30 matching lines @@
         v := url.Values{}
         v.Set("r", dest)
         return "http://login_url?" + v.Encode(), nil
 }
 
 func (m fakeMethod) LogoutURL(c context.Context, dest string) (string, error) {
         v := url.Values{}
         v.Set("r", dest)
         return "http://logout_url?" + v.Encode(), nil
 }