auth flow working for code

.gitignore

@@ -3,3 +3,6 @@
 
 # exclude built documentation, since readthedocs will build it for us anyway
 /docs/_build
+
+# exclude coverage report
+cp.out

cmd/gotosocial/main.go

@@ -95,6 +95,14 @@ func main() {
 				Value:   "postgres",
 				EnvVars: []string{envNames.DbDatabase},
 			},
+
+			// TEMPLATE FLAGS
+			&cli.StringFlag{
+				Name:    flagNames.TemplateBaseDir,
+				Usage:   "Basedir for html templating files for rendering pages and composing emails",
+				Value:   "./web/template/",
+				EnvVars: []string{envNames.TemplateBaseDir},
+			},
 		},
 		Commands: []*cli.Command{
 			{
@@ -137,12 +145,12 @@ func main() {
 func runAction(c *cli.Context, a action.GTSAction) error {
 
 	// create a new *config.Config based on the config path provided...
-	conf, err := config.New(c.String(config.GetFlagNames().ConfigPath))
+	conf, err := config.FromFile(c.String(config.GetFlagNames().ConfigPath))
 	if err != nil {
 		return fmt.Errorf("error creating config: %s", err)
 	}
 	// ... and the flags set on the *cli.Context by urfave
-	conf.ParseFlags(c)
+	conf.ParseCLIFlags(c)
 
 	// create a logger with the log level, formatting, and output splitter already set
 	log, err := log.New(conf.LogLevel)

example/config.yaml

@@ -60,3 +60,10 @@ db:
   # Examples: ["mydb","postgres","gotosocial"]
   # Default: "postgres"
   database: "postgres"
+
+# Config pertaining to templating of web pages/email notifications and the like
+template:
+  # String. Directory from which gotosocial will attempt to load html templates (.tmpl files).
+  # Examples: ["/some/absolute/path/", "./relative/path/", "../../some/weird/path/"]
+  # Default: "./web/template/"
+  baseDir: "./web/template/"

go.mod

@@ -11,7 +11,7 @@ require (
 	github.com/go-session/session v3.1.2+incompatible
 	github.com/golang/mock v1.4.4 // indirect
 	github.com/google/uuid v1.2.0 // indirect
-	github.com/gotosocial/oauth2/v4 v4.2.1-0.20210316171520-7b12112bbb88
+	github.com/gotosocial/oauth2/v4 v4.2.1-0.20210318133800-45d321d259b3
 	github.com/onsi/ginkgo v1.15.0 // indirect
 	github.com/onsi/gomega v1.10.5 // indirect
 	github.com/sirupsen/logrus v1.8.0

go.sum

@@ -107,6 +107,12 @@ github.com/gorilla/websocket v1.4.2 h1:+/TMaTYc4QFitKJxsQ7Yye35DkWvkdLcvGKqM+x0U
 github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/gotosocial/oauth2/v4 v4.2.1-0.20210316171520-7b12112bbb88 h1:YJ//HmHOYJ4srm/LA6VPNjNisneMbY6TTM1xttV/ZQU=
 github.com/gotosocial/oauth2/v4 v4.2.1-0.20210316171520-7b12112bbb88/go.mod h1:zl5kwHf/atRUrY5yOyDnk49Us1Ygs0BzdW4jKAgoiP8=
+github.com/gotosocial/oauth2/v4 v4.2.1-0.20210318132047-b7df44000ea6 h1:mWWMTK2Boy6FSCi45WB6GVCcXW3IoTVJKJiHmmdjywU=
+github.com/gotosocial/oauth2/v4 v4.2.1-0.20210318132047-b7df44000ea6/go.mod h1:zl5kwHf/atRUrY5yOyDnk49Us1Ygs0BzdW4jKAgoiP8=
+github.com/gotosocial/oauth2/v4 v4.2.1-0.20210318132554-68b81fe90e62 h1:duqoA9NSY+BFY2IVveXx5lSvIQliVvPsaNMdspkTJPc=
+github.com/gotosocial/oauth2/v4 v4.2.1-0.20210318132554-68b81fe90e62/go.mod h1:zl5kwHf/atRUrY5yOyDnk49Us1Ygs0BzdW4jKAgoiP8=
+github.com/gotosocial/oauth2/v4 v4.2.1-0.20210318133800-45d321d259b3 h1:CKRz5d7mRum+UMR88Ue33tCYcej14WjUsB59C02DDqY=
+github.com/gotosocial/oauth2/v4 v4.2.1-0.20210318133800-45d321d259b3/go.mod h1:zl5kwHf/atRUrY5yOyDnk49Us1Ygs0BzdW4jKAgoiP8=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/imkira/go-interpol v1.1.0 h1:KIiKr0VSG2CUW1hl1jpiyuzuJeKUUpC8iM1AIE7N1Vk=
 github.com/imkira/go-interpol v1.1.0/go.mod h1:z0h2/2T3XF8kyEPpRgJ3kmNv+C43p+I/CoI+jC3w2iA=

internal/api/server.go

@@ -19,6 +19,10 @@
 package api
 
 import (
+	"fmt"
+	"os"
+	"path/filepath"
+
 	"github.com/gin-contrib/sessions"
 	"github.com/gin-contrib/sessions/memstore"
 	"github.com/gin-gonic/gin"
@@ -71,6 +75,10 @@ func New(config *config.Config, logger *logrus.Logger) Server {
 	engine := gin.New()
 	store := memstore.NewStore([]byte("authentication-key"), []byte("encryption-keyencryption-key----"))
 	engine.Use(sessions.Sessions("gotosocial-session", store))
+	cwd, _ := os.Getwd()
+	tmPath := filepath.Join(cwd, fmt.Sprintf("%s*", config.TemplateConfig.BaseDir))
+	logger.Debugf("loading templates from %s", tmPath)
+	engine.LoadHTMLGlob(tmPath)
 	return &server{
 		APIGroup: engine.Group("/api").Group("/v1"),
 		logger:   logger,

internal/config/config.go

@@ -30,22 +30,35 @@ type Config struct {
 	LogLevel        string          `yaml:"logLevel"`
 	ApplicationName string          `yaml:"applicationName"`
 	DBConfig        *DBConfig       `yaml:"db"`
+	TemplateConfig  *TemplateConfig `yaml:"template"`
 }
 
-// New returns a new config, or an error if something goes amiss.
-// The path parameter is optional, for loading a configuration json from the given path.
-func New(path string) (*Config, error) {
-	config := &Config{
-		DBConfig: &DBConfig{},
-	}
-	if path != "" {
-		var err error
-		if config, err = loadFromFile(path); err != nil {
+// FromFile returns a new config from a file, or an error if something goes amiss.
+func FromFile(path string) (*Config, error) {
+	c, err := loadFromFile(path)
+	if err != nil {
 		return nil, fmt.Errorf("error creating config: %s", err)
 	}
+	return c, nil
 }
 
-	return config, nil
+// Default returns a new config with default values.
+// Not yet implemented.
+func Default() *Config {
+	// TODO: find a way of doing this without code repetition, because having to
+	// repeat all values here and elsewhere is annoying and gonna be prone to mistakes.
+	return &Config{
+		DBConfig: &DBConfig{},
+		TemplateConfig: &TemplateConfig{},
+	}
+}
+
+// Empty just returns an empty config
+func Empty() *Config {
+	return &Config{
+		DBConfig: &DBConfig{},
+		TemplateConfig: &TemplateConfig{},
+	}
 }
 
 // loadFromFile takes a path to a yaml file and attempts to load a Config object from it
@@ -63,8 +76,8 @@ func loadFromFile(path string) (*Config, error) {
 	return config, nil
 }
 
-// ParseFlags sets flags on the config using the provided Flags object
-func (c *Config) ParseFlags(f KeyedFlags) {
+// ParseCLIFlags sets flags on the config using the provided Flags object
+func (c *Config) ParseCLIFlags(f KeyedFlags) {
 	fn := GetFlagNames()
 
 	// For all of these flags, we only want to set them on the config if:
@@ -108,6 +121,11 @@ func (c *Config) ParseFlags(f KeyedFlags) {
 	if c.DBConfig.Database == "" || f.IsSet(fn.DbDatabase) {
 		c.DBConfig.Database = f.String(fn.DbDatabase)
 	}
+
+	// template flags
+	if c.TemplateConfig.BaseDir == "" || f.IsSet(fn.TemplateBaseDir) {
+		c.TemplateConfig.BaseDir = f.String(fn.TemplateBaseDir)
+	}
 }
 
 // KeyedFlags is a wrapper for any type that can store keyed flags and give them back.
@@ -130,6 +148,7 @@ type Flags struct {
 	DbUser          string
 	DbPassword      string
 	DbDatabase      string
+	TemplateBaseDir string
 }
 
 // GetFlagNames returns a struct containing the names of the various flags used for
@@ -145,6 +164,7 @@ func GetFlagNames() Flags {
 		DbUser:          "db-user",
 		DbPassword:      "db-password",
 		DbDatabase:      "db-database",
+		TemplateBaseDir: "template-basedir",
 	}
 }
 
@@ -161,5 +181,6 @@ func GetEnvNames() Flags {
 		DbUser:          "GTS_DB_USER",
 		DbPassword:      "GTS_DB_PASSWORD",
 		DbDatabase:      "GTS_DB_DATABASE",
+		TemplateBaseDir: "GTS_TEMPLATE_BASEDIR",
 	}
 }

internal/config/template.go

@@ -0,0 +1,25 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package config
+
+// TemplateConfig pertains to templating of web pages/email notifications and the like
+type TemplateConfig struct {
+	// Directory from which gotosocial will attempt to load html templates (.tmpl files).
+	BaseDir string `yaml:"baseDir"`
+}

internal/oauth/html.go

@@ -2,67 +2,8 @@
 
 const (
 	signInHTML = `
-<!DOCTYPE html>
-<html lang="en">
-<head>
-    <meta charset="UTF-8">
-    <title>Login</title>
-    <link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
-    <script src="//code.jquery.com/jquery-2.2.4.min.js"></script>
-    <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
-</head>
-
-<body>
-    <div class="container">
-        <h1>Login</h1>
-        <form action="/auth/sign_in" method="POST">
-            <div class="form-group">
-                <label for="email">Email</label>
-                <input type="text" class="form-control" name="username" required placeholder="Please enter your email address">
-            </div>
-            <div class="form-group">
-                <label for="password">Password</label>
-                <input type="password" class="form-control" name="password" placeholder="Please enter your password">
-            </div>
-            <button type="submit" class="btn btn-success">Login</button>
-        </form>
-    </div>
-</body>
-
-</html>`
+`
 
 	authorizeHTML = `
-<!DOCTYPE html>
-<html lang="en">
-  <head>
-    <meta charset="UTF-8" />
-    <title>Auth</title>
-    <link
-      rel="stylesheet"
-      href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css"
-    />
-    <script src="//code.jquery.com/jquery-2.2.4.min.js"></script>
-    <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
-  </head>
-
-  <body>
-    <div class="container">
-      <div class="jumbotron">
-        <form action="/oauth/authorize" method="POST">
-          <h1>Authorize</h1>
-          <p>The client would like to perform actions on your behalf.</p>
-          <p>
-            <button
-              type="submit"
-              class="btn btn-primary btn-lg"
-              style="width:200px;"
-            >
-              Allow
-            </button>
-          </p>
-        </form>
-      </div>
-    </div>
-  </body>
-</html>`
+`
 )

internal/oauth/oauth.go

@@ -27,6 +27,7 @@
 	"github.com/go-pg/pg/v10"
 	"github.com/gotosocial/gotosocial/internal/api"
 	"github.com/gotosocial/gotosocial/internal/gtsmodel"
+	"github.com/gotosocial/gotosocial/pkg/mastotypes"
 	"github.com/gotosocial/oauth2/v4"
 	"github.com/gotosocial/oauth2/v4/errors"
 	"github.com/gotosocial/oauth2/v4/manage"
@@ -49,12 +50,8 @@ type login struct {
 	Password string `form:"password"`
 }
 
-type authorize struct {
-	ForceLogin   string `form:"force_login,omitempty"`
-	ResponseType string `form:"response_type"`
-	ClientID     string `form:"client_id"`
-	RedirectURI  string `form:"redirect_uri"`
-	Scope        string `form:"scope,omitempty"`
+type code struct {
+	Code string `form:"code"`
 }
 
 func New(ts oauth2.TokenStore, cs oauth2.ClientStore, conn *pg.DB, log *logrus.Logger) *API {
@@ -79,6 +76,9 @@ func New(ts oauth2.TokenStore, cs oauth2.ClientStore, conn *pg.DB, log *logrus.L
 			oauth2.AuthorizationCode,
 			oauth2.Refreshing,
 		},
+		AllowedCodeChallengeMethods: []oauth2.CodeChallengeMethod{
+			oauth2.CodeChallengePlain,
+		},
 	}
 
 	srv := server.NewServer(sc, manager)
@@ -106,9 +106,13 @@ func New(ts oauth2.TokenStore, cs oauth2.ClientStore, conn *pg.DB, log *logrus.L
 func (a *API) AddRoutes(s api.Server) error {
 	s.AttachHandler(http.MethodGet, "/auth/sign_in", a.SignInGETHandler)
 	s.AttachHandler(http.MethodPost, "/auth/sign_in", a.SignInPOSTHandler)
+
 	s.AttachHandler(http.MethodPost, "/oauth/token", a.TokenHandler)
+
 	s.AttachHandler(http.MethodGet, "/oauth/authorize", a.AuthorizeGETHandler)
-	s.AttachHandler(methodAny, "/auth", a.AuthHandler)
+	s.AttachHandler(http.MethodPost, "/oauth/authorize", a.AuthorizePOSTHandler)
+
+	// s.AttachHandler(http.MethodGet, "/auth", a.AuthGETHandler)
 	return nil
 }
 
@@ -125,7 +129,7 @@ func incorrectPassword() (string, error) {
 // The form will then POST to the sign in page, which will be handled by SignInPOSTHandler
 func (a *API) SignInGETHandler(c *gin.Context) {
 	a.log.WithField("func", "SignInGETHandler").Trace("serving sign in html")
-	c.Data(http.StatusOK, "text/html; charset=utf-8", []byte(signInHTML))
+	c.HTML(http.StatusOK, "sign-in.tmpl", gin.H{})
 }
 
 // SignInPOSTHandler should be served at https://example.org/auth/sign_in.
@@ -135,15 +139,16 @@ func (a *API) SignInPOSTHandler(c *gin.Context) {
 	l := a.log.WithField("func", "SignInPOSTHandler")
 	s := sessions.Default(c)
 	form := &login{}
-	if err := c.ShouldBind(form); err != nil || form.Email == "" || form.Password == "" {
+	if err := c.ShouldBind(form); err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
 		return
 	}
 	l.Tracef("parsed form: %+v", form)
 
-	userid, err := a.ValidatePassword(form.Email, form.Password);
+	userid, err := a.ValidatePassword(form.Email, form.Password)
 	if err != nil {
 		c.String(http.StatusForbidden, err.Error())
+		return
 	}
 
 	s.Set("username", userid)
@@ -151,11 +156,12 @@ func (a *API) SignInPOSTHandler(c *gin.Context) {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 		return
 	}
+
 	l.Trace("redirecting to auth page")
-	c.Redirect(http.StatusFound, "/auth")
+	c.Redirect(http.StatusFound, "/oauth/authorize")
 }
 
-// TokenHandler should be served at https://example.org/oauth/token
+// TokenHandler should be served as a POST at https://example.org/oauth/token
 // The idea here is to serve an oauth access token to a user, which can be used for authorizing against non-public APIs.
 // See https://docs.joinmastodon.org/methods/apps/oauth/#obtain-a-token
 func (a *API) TokenHandler(c *gin.Context) {
@@ -166,13 +172,18 @@ func (a *API) TokenHandler(c *gin.Context) {
 	}
 }
 
-// AuthorizeHandler should be served as GET at https://example.org/oauth/authorize
+// AuthorizeGETHandler should be served as GET at https://example.org/oauth/authorize
 // The idea here is to present an oauth authorize page to the user, with a button
 // that they have to click to accept. See here: https://docs.joinmastodon.org/methods/apps/oauth/#authorize-a-user
 func (a *API) AuthorizeGETHandler(c *gin.Context) {
-	l := a.log.WithField("func", "AuthorizeHandler")
+	l := a.log.WithField("func", "AuthorizeGETHandler")
 	s := sessions.Default(c)
-	form := &authorize{}
+
+	v := s.Get("username")
+	if username, ok := v.(string); !ok || username == "" {
+		l.Trace("username was empty, parsing form then redirecting to sign in page")
+
+		form := &mastotypes.OAuthAuthorize{}
 
 		if err := c.ShouldBind(form); err != nil {
 			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
@@ -185,6 +196,7 @@ func (a *API) AuthorizeGETHandler(c *gin.Context) {
 			return
 		}
 
+		// save these values from the form so we can use them elsewhere in the session
 		s.Set("force_login", form.ForceLogin)
 		s.Set("response_type", form.ResponseType)
 		s.Set("client_id", form.ClientID)
@@ -192,24 +204,29 @@ func (a *API) AuthorizeGETHandler(c *gin.Context) {
 		s.Set("scope", form.Scope)
 		if err := s.Save(); err != nil {
 			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+			return
 		}
 
-	v := s.Get("username")
-	if username, ok := v.(string); !ok || username == "" {
-		l.Trace("username was empty, redirecting to sign in page")
 		c.Redirect(http.StatusFound, "/auth/sign_in")
 		return
 	}
 
 	l.Trace("serving authorize html")
-	c.Data(http.StatusOK, "text/html; charset=utf-8", []byte(authorizeHTML))
+	c.HTML(http.StatusOK, "authorize.tmpl", gin.H{})
 }
 
-// AuthHandler should be served at https://example.org/auth
-func (a *API) AuthHandler(c *gin.Context) {
-	l := a.log.WithField("func", "AuthHandler")
+// AuthorizePOSTHandler should be served as POST at https://example.org/oauth/authorize
+// The idea here is to present an oauth authorize page to the user, with a button
+// that they have to click to accept. See here: https://docs.joinmastodon.org/methods/apps/oauth/#authorize-a-user
+func (a *API) AuthorizePOSTHandler(c *gin.Context) {
+	l := a.log.WithField("func", "AuthorizePOSTHandler")
 	s := sessions.Default(c)
 
+	v := s.Get("username")
+	if username, ok := v.(string); !ok || username == "" {
+		c.JSON(http.StatusUnauthorized, gin.H{"error": "you are not signed in"})
+	}
+
 	values := url.Values{}
 
 	if v, ok := s.Get("force_login").(string); !ok {
@@ -277,7 +294,13 @@ func (a *API) AuthHandler(c *gin.Context) {
 // so that it can be used in further Oauth flows to generate a token/retreieve an oauth client from the db.
 func (a *API) ValidatePassword(email string, password string) (userid string, err error) {
 	l := a.log.WithField("func", "PasswordAuthorizationHandler")
-	l.Tracef("email %s password %s", email, password)
+
+	// make sure an email/password was provided and bail if not
+	if email == "" || password == "" {
+		l.Debug("email or password was not provided")
+		return incorrectPassword()
+	}
+
 	// first we select the user from the database based on email address, bail if no user found for that email
 	gtsUser := &gtsmodel.User{}
 	if err := a.conn.Model(gtsUser).Where("email = ?", email).Select(); err != nil {
@@ -297,8 +320,7 @@ func (a *API) ValidatePassword(email string, password string) (userid string, er
 		return incorrectPassword()
 	}
 
-	// If we've made it this far the email/password is correct so we need the oauth client-id of the user
-	// This is, conveniently, the same as the user ID, so we can just return it.
+	// If we've made it this far the email/password is correct, so we can just return the id of the user.
 	userid = gtsUser.ID
 	l.Tracef("returning (%s, %s)", userid, err)
 	return

internal/oauth/oauth_test.go

@@ -40,17 +40,24 @@ func (suite *OauthTestSuite) SetupSuite() {
 	suite.testUser = &gtsmodel.User{
 		ID:                userID,
 		EncryptedPassword: string(encryptedPassword),
-		Email:             "user@localhost",
+		Email:             "user@example.org",
 		CreatedAt:         time.Now(),
 		UpdatedAt:         time.Now(),
-		AccountID:         "some-account-id-it-doesn't-matter-really",
+		AccountID:         "some-account-id-it-doesn't-matter-really-since-this-user-doesn't-actually-have-an-account!",
 	}
 	suite.testClient = &oauthClient{
 		ID:     "a-known-client-id",
 		Secret: "some-secret",
-		Domain: "http://localhost:8080",
+		Domain: "https://example.org",
 		UserID: userID,
 	}
+
+	// because go tests are run within the test package directory, we need to fiddle with the templateconfig
+	// basedir in a way that we wouldn't normally have to do when running the binary, in order to make
+	// the templates actually load
+	c := config.Empty()
+	c.TemplateConfig.BaseDir = "../../web/template/"
+	suite.config = c
 }
 
 // SetupTest creates a postgres connection and creates the oauth_clients table before each test
@@ -114,7 +121,7 @@ func (suite *OauthTestSuite) TestAPIInitialize() {
 	api.AddRoutes(r)
 	go r.Start()
 	time.Sleep(30 * time.Second)
-	// http://localhost:8080/oauth/authorize?client_id=a-known-client-id&redirect_uri=''&response_type=code
+	// http://localhost:8080/oauth/authorize?client_id=a-known-client-id&response_type=code&redirect_uri=https://example.org
 }
 
 func TestOauthTestSuite(t *testing.T) {

pkg/mastotypes/oauth.go

@@ -0,0 +1,37 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package mastotypes
+
+// OAuthAuthorize represents a request sent to https://example.org/oauth/authorize
+// See here: https://docs.joinmastodon.org/methods/apps/oauth/
+type OAuthAuthorize struct {
+	// Forces the user to re-login, which is necessary for authorizing with multiple accounts from the same instance.
+	ForceLogin   string `form:"force_login,omitempty"`
+	// Should be set equal to `code`.
+	ResponseType string `form:"response_type"`
+	// Client ID, obtained during app registration.
+	ClientID     string `form:"client_id"`
+	// Set a URI to redirect the user to.
+	// If this parameter is set to urn:ietf:wg:oauth:2.0:oob then the authorization code will be shown instead.
+	// Must match one of the redirect URIs declared during app registration.
+	RedirectURI  string `form:"redirect_uri"`
+	// List of requested OAuth scopes, separated by spaces (or by pluses, if using query parameters).
+	// Must be a subset of scopes declared during app registration. If not provided, defaults to read.
+	Scope        string `form:"scope,omitempty"`
+}

web/template/authorize.tmpl

@@ -0,0 +1,33 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <title>Auth</title>
+    <link
+      rel="stylesheet"
+      href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css"
+    />
+    <script src="//code.jquery.com/jquery-2.2.4.min.js"></script>
+    <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
+  </head>
+
+  <body>
+    <div class="container">
+      <div class="jumbotron">
+        <form action="/oauth/authorize" method="POST">
+          <h1>Authorize</h1>
+          <p>The client would like to perform actions on your behalf.</p>
+          <p>
+            <button
+              type="submit"
+              class="btn btn-primary btn-lg"
+              style="width:200px;"
+            >
+              Allow
+            </button>
+          </p>
+        </form>
+      </div>
+    </div>
+  </body>
+</html>

web/template/sign-in.tmpl

@@ -0,0 +1,28 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>Login</title>
+    <link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
+    <script src="//code.jquery.com/jquery-2.2.4.min.js"></script>
+    <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
+</head>
+
+<body>
+    <div class="container">
+        <h1>Login</h1>
+        <form action="/auth/sign_in" method="POST">
+            <div class="form-group">
+                <label for="email">Email</label>
+                <input type="text" class="form-control" name="username" required placeholder="Please enter your email address">
+            </div>
+            <div class="form-group">
+                <label for="password">Password</label>
+                <input type="password" class="form-control" name="password" placeholder="Please enter your password">
+            </div>
+            <button type="submit" class="btn btn-success">Login</button>
+        </form>
+    </div>
+</body>
+
+</html>