Oauth/token (#7)

* add host and protocol options

* some fiddling

* tidying up and comments

* tick off /oauth/token

* tidying a bit

* tidying

* go mod tidy

* allow attaching middleware to server

* add middleware

* more user friendly

* add comments

* comments

* store account + app

* tidying

* lots of restructuring

* lint + tidy

8 files changed, 1240 insertions, 0 deletions

diff --git a/internal/module/account/account.go b/internal/module/account/account.go
new file mode 100644
index 000000000..d82d96e78
--- /dev/null
+++ b/internal/module/account/account.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 account
+
+import (
+	"github.com/gotosocial/gotosocial/internal/module"
+	"github.com/gotosocial/gotosocial/internal/router"
+)
+
+type accountModule struct {
+}
+
+// New returns a new account module
+func New() module.ClientAPIModule {
+	return &accountModule{}
+}
+
+// Route attaches all routes from this module to the given router
+func (m *accountModule) Route(r router.Router) error {
+	return nil
+}
diff --git a/internal/module/module.go b/internal/module/module.go
new file mode 100644
index 000000000..8618d2857
--- /dev/null
+++ b/internal/module/module.go
@@ -0,0 +1,29 @@
+/*
+   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 module is basically a wrapper for a lot of modules (in subdirectories) that satisfy the ClientAPIModule interface.
+package module
+
+import "github.com/gotosocial/gotosocial/internal/router"
+
+// ClientAPIModule represents a chunk of code (usually contained in a single package) that adds a set
+// of functionalities and side effects to a router, by mapping routes and handlers onto it--in other words, a REST API ;)
+// A ClientAPIMpdule corresponds roughly to one main path of the gotosocial REST api, for example /api/v1/accounts/ or /oauth/
+type ClientAPIModule interface {
+	Route(s router.Router) error
+}
diff --git a/internal/module/oauth/README.md b/internal/module/oauth/README.md
new file mode 100644
index 000000000..3d8427302
--- /dev/null
+++ b/internal/module/oauth/README.md
@@ -0,0 +1,5 @@
+# oauth
+
+This package provides uses the [GoToSocial oauth2](https://github.com/gotosocial/oauth2) module (forked from [go-oauth2](https://github.com/go-oauth2/oauth2)) to provide [oauth2](https://www.oauth.com/) functionality to the GoToSocial client API.
+
+It also provides a handler/middleware for attaching to the Gin engine for validating authenticated users.
diff --git a/internal/module/oauth/clientstore.go b/internal/module/oauth/clientstore.go
new file mode 100644
index 000000000..f99c160c2
--- /dev/null
+++ b/internal/module/oauth/clientstore.go
@@ -0,0 +1,73 @@
+/*
+   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 oauth
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/gotosocial/gotosocial/internal/db"
+	"github.com/gotosocial/oauth2/v4"
+	"github.com/gotosocial/oauth2/v4/models"
+)
+
+type clientStore struct {
+	db db.DB
+}
+
+func newClientStore(db db.DB) oauth2.ClientStore {
+	pts := &clientStore{
+		db: db,
+	}
+	return pts
+}
+
+func (cs *clientStore) GetByID(ctx context.Context, clientID string) (oauth2.ClientInfo, error) {
+	poc := &oauthClient{
+		ID: clientID,
+	}
+	if err := cs.db.GetByID(clientID, poc); err != nil {
+		return nil, fmt.Errorf("database error: %s", err)
+	}
+	return models.New(poc.ID, poc.Secret, poc.Domain, poc.UserID), nil
+}
+
+func (cs *clientStore) Set(ctx context.Context, id string, cli oauth2.ClientInfo) error {
+	poc := &oauthClient{
+		ID:     cli.GetID(),
+		Secret: cli.GetSecret(),
+		Domain: cli.GetDomain(),
+		UserID: cli.GetUserID(),
+	}
+	return cs.db.UpdateByID(id, poc)
+}
+
+func (cs *clientStore) Delete(ctx context.Context, id string) error {
+	poc := &oauthClient{
+		ID: id,
+	}
+	return cs.db.DeleteByID(id, poc)
+}
+
+type oauthClient struct {
+	ID     string
+	Secret string
+	Domain string
+	UserID string
+}
diff --git a/internal/module/oauth/clientstore_test.go b/internal/module/oauth/clientstore_test.go
new file mode 100644
index 000000000..bca002411
--- /dev/null
+++ b/internal/module/oauth/clientstore_test.go
@@ -0,0 +1,144 @@
+/*
+   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 oauth
+
+import (
+	"context"
+	"testing"
+
+	"github.com/gotosocial/gotosocial/internal/config"
+	"github.com/gotosocial/gotosocial/internal/db"
+	"github.com/gotosocial/oauth2/v4/models"
+	"github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/suite"
+)
+
+type PgClientStoreTestSuite struct {
+	suite.Suite
+	db               db.DB
+	testClientID     string
+	testClientSecret string
+	testClientDomain string
+	testClientUserID string
+}
+
+const ()
+
+// SetupSuite sets some variables on the suite that we can use as consts (more or less) throughout
+func (suite *PgClientStoreTestSuite) SetupSuite() {
+	suite.testClientID = "test-client-id"
+	suite.testClientSecret = "test-client-secret"
+	suite.testClientDomain = "https://example.org"
+	suite.testClientUserID = "test-client-user-id"
+}
+
+// SetupTest creates a postgres connection and creates the oauth_clients table before each test
+func (suite *PgClientStoreTestSuite) SetupTest() {
+	log := logrus.New()
+	log.SetLevel(logrus.TraceLevel)
+	c := config.Empty()
+	c.DBConfig = &config.DBConfig{
+		Type:            "postgres",
+		Address:         "localhost",
+		Port:            5432,
+		User:            "postgres",
+		Password:        "postgres",
+		Database:        "postgres",
+		ApplicationName: "gotosocial",
+	}
+	db, err := db.New(context.Background(), c, log)
+	if err != nil {
+		logrus.Panicf("error creating database connection: %s", err)
+	}
+
+	suite.db = db
+
+	models := []interface{}{
+		&oauthClient{},
+	}
+
+	for _, m := range models {
+		if err := suite.db.CreateTable(m); err != nil {
+			logrus.Panicf("db connection error: %s", err)
+		}
+	}
+}
+
+// TearDownTest drops the oauth_clients table and closes the pg connection after each test
+func (suite *PgClientStoreTestSuite) TearDownTest() {
+	models := []interface{}{
+		&oauthClient{},
+	}
+	for _, m := range models {
+		if err := suite.db.DropTable(m); err != nil {
+			logrus.Panicf("error dropping table: %s", err)
+		}
+	}
+	if err := suite.db.Stop(context.Background()); err != nil {
+		logrus.Panicf("error closing db connection: %s", err)
+	}
+	suite.db = nil
+}
+
+func (suite *PgClientStoreTestSuite) TestClientStoreSetAndGet() {
+	// set a new client in the store
+	cs := newClientStore(suite.db)
+	if err := cs.Set(context.Background(), suite.testClientID, models.New(suite.testClientID, suite.testClientSecret, suite.testClientDomain, suite.testClientUserID)); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	// fetch that client from the store
+	client, err := cs.GetByID(context.Background(), suite.testClientID)
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	// check that the values are the same
+	suite.NotNil(client)
+	suite.EqualValues(models.New(suite.testClientID, suite.testClientSecret, suite.testClientDomain, suite.testClientUserID), client)
+}
+
+func (suite *PgClientStoreTestSuite) TestClientSetAndDelete() {
+	// set a new client in the store
+	cs := newClientStore(suite.db)
+	if err := cs.Set(context.Background(), suite.testClientID, models.New(suite.testClientID, suite.testClientSecret, suite.testClientDomain, suite.testClientUserID)); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	// fetch the client from the store
+	client, err := cs.GetByID(context.Background(), suite.testClientID)
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	// check that the values are the same
+	suite.NotNil(client)
+	suite.EqualValues(models.New(suite.testClientID, suite.testClientSecret, suite.testClientDomain, suite.testClientUserID), client)
+	if err := cs.Delete(context.Background(), suite.testClientID); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	// try to get the deleted client; we should get an error
+	deletedClient, err := cs.GetByID(context.Background(), suite.testClientID)
+	suite.Assert().Nil(deletedClient)
+	suite.Assert().NotNil(err)
+}
+
+func TestPgClientStoreTestSuite(t *testing.T) {
+	suite.Run(t, new(PgClientStoreTestSuite))
+}
diff --git a/internal/module/oauth/oauth.go b/internal/module/oauth/oauth.go
new file mode 100644
index 000000000..4436f7a8d
--- /dev/null
+++ b/internal/module/oauth/oauth.go
@@ -0,0 +1,510 @@
+/*
+   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 oauth is a module that provides oauth functionality to a router.
+// It adds the following paths:
+//    /api/v1/apps
+//    /auth/sign_in
+//    /oauth/token
+//    /oauth/authorize
+// It also includes the oauthTokenMiddleware, which can be attached to a router to authenticate every request by Bearer token.
+package oauth
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"github.com/gin-contrib/sessions"
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+	"github.com/gotosocial/gotosocial/internal/db"
+	"github.com/gotosocial/gotosocial/internal/gtsmodel"
+	"github.com/gotosocial/gotosocial/internal/module"
+	"github.com/gotosocial/gotosocial/internal/router"
+	"github.com/gotosocial/gotosocial/pkg/mastotypes"
+	"github.com/gotosocial/oauth2/v4"
+	"github.com/gotosocial/oauth2/v4/errors"
+	"github.com/gotosocial/oauth2/v4/manage"
+	"github.com/gotosocial/oauth2/v4/server"
+	"github.com/sirupsen/logrus"
+	"golang.org/x/crypto/bcrypt"
+)
+
+const (
+	appsPath           = "/api/v1/apps"
+	authSignInPath     = "/auth/sign_in"
+	oauthTokenPath     = "/oauth/token"
+	oauthAuthorizePath = "/oauth/authorize"
+)
+
+// oauthModule is an oauth2 oauthModule that satisfies the ClientAPIModule interface
+type oauthModule struct {
+	oauthManager *manage.Manager
+	oauthServer  *server.Server
+	db           db.DB
+	log          *logrus.Logger
+}
+
+type login struct {
+	Email    string `form:"username"`
+	Password string `form:"password"`
+}
+
+// New returns a new oauth module
+func New(ts oauth2.TokenStore, cs oauth2.ClientStore, db db.DB, log *logrus.Logger) module.ClientAPIModule {
+	manager := manage.NewDefaultManager()
+	manager.MapTokenStorage(ts)
+	manager.MapClientStorage(cs)
+	manager.SetAuthorizeCodeTokenCfg(manage.DefaultAuthorizeCodeTokenCfg)
+	sc := &server.Config{
+		TokenType: "Bearer",
+		// Must follow the spec.
+		AllowGetAccessRequest: false,
+		// Support only the non-implicit flow.
+		AllowedResponseTypes: []oauth2.ResponseType{oauth2.Code},
+		// Allow:
+		// - Authorization Code (for first & third parties)
+		AllowedGrantTypes: []oauth2.GrantType{
+			oauth2.AuthorizationCode,
+		},
+		AllowedCodeChallengeMethods: []oauth2.CodeChallengeMethod{oauth2.CodeChallengePlain},
+	}
+
+	srv := server.NewServer(sc, manager)
+	srv.SetInternalErrorHandler(func(err error) *errors.Response {
+		log.Errorf("internal oauth error: %s", err)
+		return nil
+	})
+
+	srv.SetResponseErrorHandler(func(re *errors.Response) {
+		log.Errorf("internal response error: %s", re.Error)
+	})
+
+	m := &oauthModule{
+		oauthManager: manager,
+		oauthServer:  srv,
+		db:           db,
+		log:          log,
+	}
+
+	m.oauthServer.SetUserAuthorizationHandler(m.userAuthorizationHandler)
+	m.oauthServer.SetClientInfoHandler(server.ClientFormHandler)
+	return m
+}
+
+// Route satisfies the RESTAPIModule interface
+func (m *oauthModule) Route(s router.Router) error {
+	s.AttachHandler(http.MethodPost, appsPath, m.appsPOSTHandler)
+
+	s.AttachHandler(http.MethodGet, authSignInPath, m.signInGETHandler)
+	s.AttachHandler(http.MethodPost, authSignInPath, m.signInPOSTHandler)
+
+	s.AttachHandler(http.MethodPost, oauthTokenPath, m.tokenPOSTHandler)
+
+	s.AttachHandler(http.MethodGet, oauthAuthorizePath, m.authorizeGETHandler)
+	s.AttachHandler(http.MethodPost, oauthAuthorizePath, m.authorizePOSTHandler)
+
+	s.AttachMiddleware(m.oauthTokenMiddleware)
+
+	return nil
+}
+
+/*
+	MAIN HANDLERS -- serve these through a server/router
+*/
+
+// appsPOSTHandler should be served at https://example.org/api/v1/apps
+// It is equivalent to: https://docs.joinmastodon.org/methods/apps/
+func (m *oauthModule) appsPOSTHandler(c *gin.Context) {
+	l := m.log.WithField("func", "AppsPOSTHandler")
+	l.Trace("entering AppsPOSTHandler")
+
+	form := &mastotypes.ApplicationPOSTRequest{}
+	if err := c.ShouldBind(form); err != nil {
+		c.JSON(http.StatusUnprocessableEntity, gin.H{"error": err.Error()})
+		return
+	}
+
+	// permitted length for most fields
+	permittedLength := 64
+	// redirect can be a bit bigger because we probably need to encode data in the redirect uri
+	permittedRedirect := 256
+
+	// check lengths of fields before proceeding so the user can't spam huge entries into the database
+	if len(form.ClientName) > permittedLength {
+		c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("client_name must be less than %d bytes", permittedLength)})
+		return
+	}
+	if len(form.Website) > permittedLength {
+		c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("website must be less than %d bytes", permittedLength)})
+		return
+	}
+	if len(form.RedirectURIs) > permittedRedirect {
+		c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("redirect_uris must be less than %d bytes", permittedRedirect)})
+		return
+	}
+	if len(form.Scopes) > permittedLength {
+		c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("scopes must be less than %d bytes", permittedLength)})
+		return
+	}
+
+	// set default 'read' for scopes if it's not set, this follows the default of the mastodon api https://docs.joinmastodon.org/methods/apps/
+	var scopes string
+	if form.Scopes == "" {
+		scopes = "read"
+	} else {
+		scopes = form.Scopes
+	}
+
+	// generate new IDs for this application and its associated client
+	clientID := uuid.NewString()
+	clientSecret := uuid.NewString()
+	vapidKey := uuid.NewString()
+
+	// generate the application to put in the database
+	app := &gtsmodel.Application{
+		Name:         form.ClientName,
+		Website:      form.Website,
+		RedirectURI:  form.RedirectURIs,
+		ClientID:     clientID,
+		ClientSecret: clientSecret,
+		Scopes:       scopes,
+		VapidKey:     vapidKey,
+	}
+
+	// chuck it in the db
+	if err := m.db.Put(app); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	// now we need to model an oauth client from the application that the oauth library can use
+	oc := &oauthClient{
+		ID:     clientID,
+		Secret: clientSecret,
+		Domain: form.RedirectURIs,
+		UserID: "", // This client isn't yet associated with a specific user,  it's just an app client right now
+	}
+
+	// chuck it in the db
+	if err := m.db.Put(oc); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	// done, return the new app information per the spec here: https://docs.joinmastodon.org/methods/apps/
+	c.JSON(http.StatusOK, app.ToMastotype())
+}
+
+// signInGETHandler should be served at https://example.org/auth/sign_in.
+// The idea is to present a sign in page to the user, where they can enter their username and password.
+// The form will then POST to the sign in page, which will be handled by SignInPOSTHandler
+func (m *oauthModule) signInGETHandler(c *gin.Context) {
+	m.log.WithField("func", "SignInGETHandler").Trace("serving sign in html")
+	c.HTML(http.StatusOK, "sign-in.tmpl", gin.H{})
+}
+
+// signInPOSTHandler should be served at https://example.org/auth/sign_in.
+// The idea is to present a sign in page to the user, where they can enter their username and password.
+// The handler will then redirect to the auth handler served at /auth
+func (m *oauthModule) signInPOSTHandler(c *gin.Context) {
+	l := m.log.WithField("func", "SignInPOSTHandler")
+	s := sessions.Default(c)
+	form := &login{}
+	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 := m.validatePassword(form.Email, form.Password)
+	if err != nil {
+		c.String(http.StatusForbidden, err.Error())
+		return
+	}
+
+	s.Set("userid", userid)
+	if err := s.Save(); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	l.Trace("redirecting to auth page")
+	c.Redirect(http.StatusFound, oauthAuthorizePath)
+}
+
+// tokenPOSTHandler 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 (m *oauthModule) tokenPOSTHandler(c *gin.Context) {
+	l := m.log.WithField("func", "TokenPOSTHandler")
+	l.Trace("entered TokenPOSTHandler")
+	if err := m.oauthServer.HandleTokenRequest(c.Writer, c.Request); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+	}
+}
+
+// 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 (m *oauthModule) authorizeGETHandler(c *gin.Context) {
+	l := m.log.WithField("func", "AuthorizeGETHandler")
+	s := sessions.Default(c)
+
+	// UserID will be set in the session by AuthorizePOSTHandler if the caller has already gone through the authentication flow
+	// If it's not set, then we don't know yet who the user is, so we need to redirect them to the sign in page.
+	userID, ok := s.Get("userid").(string)
+	if !ok || userID == "" {
+		l.Trace("userid was empty, parsing form then redirecting to sign in page")
+		if err := parseAuthForm(c, l); err != nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		} else {
+			c.Redirect(http.StatusFound, authSignInPath)
+		}
+		return
+	}
+
+	// We can use the client_id on the session to retrieve info about the app associated with the client_id
+	clientID, ok := s.Get("client_id").(string)
+	if !ok || clientID == "" {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "no client_id found in session"})
+		return
+	}
+	app := &gtsmodel.Application{
+		ClientID: clientID,
+	}
+	if err := m.db.GetWhere("client_id", app.ClientID, app); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": fmt.Sprintf("no application found for client id %s", clientID)})
+		return
+	}
+
+	// we can also use the userid of the user to fetch their username from the db to greet them nicely <3
+	user := &gtsmodel.User{
+		ID: userID,
+	}
+	if err := m.db.GetByID(user.ID, user); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	acct := &gtsmodel.Account{
+		ID: user.AccountID,
+	}
+
+	if err := m.db.GetByID(acct.ID, acct); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	// Finally we should also get the redirect and scope of this particular request, as stored in the session.
+	redirect, ok := s.Get("redirect_uri").(string)
+	if !ok || redirect == "" {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "no redirect_uri found in session"})
+		return
+	}
+	scope, ok := s.Get("scope").(string)
+	if !ok || scope == "" {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "no scope found in session"})
+		return
+	}
+
+	// the authorize template will display a form to the user where they can get some information
+	// about the app that's trying to authorize, and the scope of the request.
+	// They can then approve it if it looks OK to them, which will POST to the AuthorizePOSTHandler
+	l.Trace("serving authorize html")
+	c.HTML(http.StatusOK, "authorize.tmpl", gin.H{
+		"appname":    app.Name,
+		"appwebsite": app.Website,
+		"redirect":   redirect,
+		"scope":      scope,
+		"user":       acct.Username,
+	})
+}
+
+// authorizePOSTHandler should be served as POST at https://example.org/oauth/authorize
+// At this point we assume that the user has A) logged in and B) accepted that the app should act for them,
+// so we should proceed with the authentication flow and generate an oauth token for them if we can.
+// See here: https://docs.joinmastodon.org/methods/apps/oauth/#authorize-a-user
+func (m *oauthModule) authorizePOSTHandler(c *gin.Context) {
+	l := m.log.WithField("func", "AuthorizePOSTHandler")
+	s := sessions.Default(c)
+
+	// At this point we know the user has said 'yes' to allowing the application and oauth client
+	// work for them, so we can set the
+
+	// We need to retrieve the original form submitted to the authorizeGEThandler, and
+	// recreate it on the request so that it can be used further by the oauth2 library.
+	// So first fetch all the values from the session.
+	forceLogin, ok := s.Get("force_login").(string)
+	if !ok {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "session missing force_login"})
+		return
+	}
+	responseType, ok := s.Get("response_type").(string)
+	if !ok || responseType == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "session missing response_type"})
+		return
+	}
+	clientID, ok := s.Get("client_id").(string)
+	if !ok || clientID == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "session missing client_id"})
+		return
+	}
+	redirectURI, ok := s.Get("redirect_uri").(string)
+	if !ok || redirectURI == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "session missing redirect_uri"})
+		return
+	}
+	scope, ok := s.Get("scope").(string)
+	if !ok {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "session missing scope"})
+		return
+	}
+	userID, ok := s.Get("userid").(string)
+	if !ok {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "session missing userid"})
+		return
+	}
+	// we're done with the session so we can clear it now
+	s.Clear()
+
+	// now set the values on the request
+	values := url.Values{}
+	values.Set("force_login", forceLogin)
+	values.Set("response_type", responseType)
+	values.Set("client_id", clientID)
+	values.Set("redirect_uri", redirectURI)
+	values.Set("scope", scope)
+	values.Set("userid", userID)
+	c.Request.Form = values
+	l.Tracef("values on request set to %+v", c.Request.Form)
+
+	// and proceed with authorization using the oauth2 library
+	if err := m.oauthServer.HandleAuthorizeRequest(c.Writer, c.Request); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+	}
+}
+
+/*
+	MIDDLEWARE
+*/
+
+// oauthTokenMiddleware
+func (m *oauthModule) oauthTokenMiddleware(c *gin.Context) {
+	l := m.log.WithField("func", "ValidatePassword")
+	l.Trace("entering OauthTokenMiddleware")
+	if ti, err := m.oauthServer.ValidationBearerToken(c.Request); err == nil {
+		l.Tracef("authenticated user %s with bearer token, scope is %s", ti.GetUserID(), ti.GetScope())
+		c.Set("authenticated_user", ti.GetUserID())
+
+	} else {
+		l.Trace("continuing with unauthenticated request")
+	}
+}
+
+/*
+	SUB-HANDLERS -- don't serve these directly, they should be attached to the oauth2 server or used inside handler funcs
+*/
+
+// validatePassword takes an email address and a password.
+// The goal is to authenticate the password against the one for that email
+// address stored in the database. If OK, we return the userid (a uuid) for that user,
+// so that it can be used in further Oauth flows to generate a token/retreieve an oauth client from the db.
+func (m *oauthModule) validatePassword(email string, password string) (userid string, err error) {
+	l := m.log.WithField("func", "ValidatePassword")
+
+	// 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 := m.db.GetWhere("email", email, gtsUser); err != nil {
+		l.Debugf("user %s was not retrievable from db during oauth authorization attempt: %s", email, err)
+		return incorrectPassword()
+	}
+
+	// make sure a password is actually set and bail if not
+	if gtsUser.EncryptedPassword == "" {
+		l.Warnf("encrypted password for user %s was empty for some reason", gtsUser.Email)
+		return incorrectPassword()
+	}
+
+	// compare the provided password with the encrypted one from the db, bail if they don't match
+	if err := bcrypt.CompareHashAndPassword([]byte(gtsUser.EncryptedPassword), []byte(password)); err != nil {
+		l.Debugf("password hash didn't match for user %s during login attempt: %s", gtsUser.Email, err)
+		return incorrectPassword()
+	}
+
+	// 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
+}
+
+// incorrectPassword is just a little helper function to use in the ValidatePassword function
+func incorrectPassword() (string, error) {
+	return "", errors.New("password/email combination was incorrect")
+}
+
+// userAuthorizationHandler gets the user's ID from the 'userid' field of the request form,
+// or redirects to the /auth/sign_in page, if this key is not present.
+func (m *oauthModule) userAuthorizationHandler(w http.ResponseWriter, r *http.Request) (userID string, err error) {
+	l := m.log.WithField("func", "UserAuthorizationHandler")
+	userID = r.FormValue("userid")
+	if userID == "" {
+		return "", errors.New("userid was empty, redirecting to sign in page")
+	}
+	l.Tracef("returning userID %s", userID)
+	return userID, err
+}
+
+// parseAuthForm parses the OAuthAuthorize form in the gin context, and stores
+// the values in the form into the session.
+func parseAuthForm(c *gin.Context, l *logrus.Entry) error {
+	s := sessions.Default(c)
+
+	// first make sure they've filled out the authorize form with the required values
+	form := &mastotypes.OAuthAuthorize{}
+	if err := c.ShouldBind(form); err != nil {
+		return err
+	}
+	l.Tracef("parsed form: %+v", form)
+
+	// these fields are *required* so check 'em
+	if form.ResponseType == "" || form.ClientID == "" || form.RedirectURI == "" {
+		return errors.New("missing one of: response_type, client_id or redirect_uri")
+	}
+
+	// set default scope to read
+	if form.Scope == "" {
+		form.Scope = "read"
+	}
+
+	// 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)
+	s.Set("redirect_uri", form.RedirectURI)
+	s.Set("scope", form.Scope)
+	return s.Save()
+}
diff --git a/internal/module/oauth/oauth_test.go b/internal/module/oauth/oauth_test.go
new file mode 100644
index 000000000..adfb40ac5
--- /dev/null
+++ b/internal/module/oauth/oauth_test.go
@@ -0,0 +1,191 @@
+/*
+   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 oauth
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/gotosocial/gotosocial/internal/config"
+	"github.com/gotosocial/gotosocial/internal/db"
+	"github.com/gotosocial/gotosocial/internal/gtsmodel"
+	"github.com/gotosocial/gotosocial/internal/router"
+	"github.com/gotosocial/oauth2/v4"
+	"github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/suite"
+	"golang.org/x/crypto/bcrypt"
+)
+
+type OauthTestSuite struct {
+	suite.Suite
+	tokenStore      oauth2.TokenStore
+	clientStore     oauth2.ClientStore
+	db              db.DB
+	testAccount     *gtsmodel.Account
+	testApplication *gtsmodel.Application
+	testUser        *gtsmodel.User
+	testClient      *oauthClient
+	config          *config.Config
+}
+
+// SetupSuite sets some variables on the suite that we can use as consts (more or less) throughout
+func (suite *OauthTestSuite) SetupSuite() {
+	c := config.Empty()
+	// we're running on localhost without https so set the protocol to http
+	c.Protocol = "http"
+	// just for testing
+	c.Host = "localhost:8080"
+	// 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.TemplateConfig.BaseDir = "../../../web/template/"
+	c.DBConfig = &config.DBConfig{
+		Type:            "postgres",
+		Address:         "localhost",
+		Port:            5432,
+		User:            "postgres",
+		Password:        "postgres",
+		Database:        "postgres",
+		ApplicationName: "gotosocial",
+	}
+	suite.config = c
+
+	encryptedPassword, err := bcrypt.GenerateFromPassword([]byte("password"), bcrypt.DefaultCost)
+	if err != nil {
+		logrus.Panicf("error encrypting user pass: %s", err)
+	}
+
+	acctID := uuid.NewString()
+
+	suite.testAccount = &gtsmodel.Account{
+		ID:       acctID,
+		Username: "test_user",
+	}
+	suite.testUser = &gtsmodel.User{
+		EncryptedPassword: string(encryptedPassword),
+		Email:             "user@example.org",
+		AccountID:         acctID,
+	}
+	suite.testClient = &oauthClient{
+		ID:     "a-known-client-id",
+		Secret: "some-secret",
+		Domain: fmt.Sprintf("%s://%s", c.Protocol, c.Host),
+	}
+	suite.testApplication = &gtsmodel.Application{
+		Name:         "a test application",
+		Website:      "https://some-application-website.com",
+		RedirectURI:  "http://localhost:8080",
+		ClientID:     "a-known-client-id",
+		ClientSecret: "some-secret",
+		Scopes:       "read",
+		VapidKey:     uuid.NewString(),
+	}
+}
+
+// SetupTest creates a postgres connection and creates the oauth_clients table before each test
+func (suite *OauthTestSuite) SetupTest() {
+
+	log := logrus.New()
+	log.SetLevel(logrus.TraceLevel)
+	db, err := db.New(context.Background(), suite.config, log)
+	if err != nil {
+		logrus.Panicf("error creating database connection: %s", err)
+	}
+
+	suite.db = db
+
+	models := []interface{}{
+		&oauthClient{},
+		&oauthToken{},
+		&gtsmodel.User{},
+		&gtsmodel.Account{},
+		&gtsmodel.Application{},
+	}
+
+	for _, m := range models {
+		if err := suite.db.CreateTable(m); err != nil {
+			logrus.Panicf("db connection error: %s", err)
+		}
+	}
+
+	suite.tokenStore = newTokenStore(context.Background(), suite.db, logrus.New())
+	suite.clientStore = newClientStore(suite.db)
+
+	if err := suite.db.Put(suite.testAccount); err != nil {
+		logrus.Panicf("could not insert test account into db: %s", err)
+	}
+	if err := suite.db.Put(suite.testUser); err != nil {
+		logrus.Panicf("could not insert test user into db: %s", err)
+	}
+	if err := suite.db.Put(suite.testClient); err != nil {
+		logrus.Panicf("could not insert test client into db: %s", err)
+	}
+	if err := suite.db.Put(suite.testApplication); err != nil {
+		logrus.Panicf("could not insert test application into db: %s", err)
+	}
+
+}
+
+// TearDownTest drops the oauth_clients table and closes the pg connection after each test
+func (suite *OauthTestSuite) TearDownTest() {
+	models := []interface{}{
+		&oauthClient{},
+		&oauthToken{},
+		&gtsmodel.User{},
+		&gtsmodel.Account{},
+		&gtsmodel.Application{},
+	}
+	for _, m := range models {
+		if err := suite.db.DropTable(m); err != nil {
+			logrus.Panicf("error dropping table: %s", err)
+		}
+	}
+	if err := suite.db.Stop(context.Background()); err != nil {
+		logrus.Panicf("error closing db connection: %s", err)
+	}
+	suite.db = nil
+}
+
+func (suite *OauthTestSuite) TestAPIInitialize() {
+	log := logrus.New()
+	log.SetLevel(logrus.TraceLevel)
+
+	r, err := router.New(suite.config, log)
+	if err != nil {
+		suite.FailNow(fmt.Sprintf("error mapping routes onto router: %s", err))
+	}
+
+	api := New(suite.tokenStore, suite.clientStore, suite.db, log)
+	if err := api.Route(r); err != nil {
+		suite.FailNow(fmt.Sprintf("error mapping routes onto router: %s", err))
+	}
+
+	go r.Start()
+	time.Sleep(60 * time.Second)
+	// http://localhost:8080/oauth/authorize?client_id=a-known-client-id&response_type=code&redirect_uri=http://localhost:8080&scope=read
+	// curl -v -F client_id=a-known-client-id -F client_secret=some-secret -F redirect_uri=http://localhost:8080 -F code=[ INSERT CODE HERE ] -F grant_type=authorization_code localhost:8080/oauth/token
+	// curl -v -H "Authorization: Bearer [INSERT TOKEN HERE]" http://localhost:8080
+}
+
+func TestOauthTestSuite(t *testing.T) {
+	suite.Run(t, new(OauthTestSuite))
+}
diff --git a/internal/module/oauth/tokenstore.go b/internal/module/oauth/tokenstore.go
new file mode 100644
index 000000000..d8a6d5814
--- /dev/null
+++ b/internal/module/oauth/tokenstore.go
@@ -0,0 +1,251 @@
+/*
+   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 oauth
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/gotosocial/gotosocial/internal/db"
+	"github.com/gotosocial/oauth2/v4"
+	"github.com/gotosocial/oauth2/v4/models"
+	"github.com/sirupsen/logrus"
+)
+
+// tokenStore is an implementation of oauth2.TokenStore, which uses our db interface as a storage backend.
+type tokenStore struct {
+	oauth2.TokenStore
+	db  db.DB
+	log *logrus.Logger
+}
+
+// newTokenStore returns a token store that satisfies the oauth2.TokenStore interface.
+//
+// In order to allow tokens to 'expire', it will also set off a goroutine that iterates through
+// the tokens in the DB once per minute and deletes any that have expired.
+func newTokenStore(ctx context.Context, db db.DB, log *logrus.Logger) oauth2.TokenStore {
+	pts := &tokenStore{
+		db:  db,
+		log: log,
+	}
+
+	// set the token store to clean out expired tokens once per minute, or return if we're done
+	go func(ctx context.Context, pts *tokenStore, log *logrus.Logger) {
+	cleanloop:
+		for {
+			select {
+			case <-ctx.Done():
+				log.Info("breaking cleanloop")
+				break cleanloop
+			case <-time.After(1 * time.Minute):
+				log.Debug("sweeping out old oauth entries broom broom")
+				if err := pts.sweep(); err != nil {
+					log.Errorf("error while sweeping oauth entries: %s", err)
+				}
+			}
+		}
+	}(ctx, pts, log)
+	return pts
+}
+
+// sweep clears out old tokens that have expired; it should be run on a loop about once per minute or so.
+func (pts *tokenStore) sweep() error {
+	// select *all* tokens from the db
+	// todo: if this becomes expensive (ie., there are fucking LOADS of tokens) then figure out a better way.
+	tokens := new([]*oauthToken)
+	if err := pts.db.GetAll(tokens); err != nil {
+		return err
+	}
+
+	// iterate through and remove expired tokens
+	now := time.Now()
+	for _, pgt := range *tokens {
+		// The zero value of a time.Time is 00:00 january 1 1970, which will always be before now. So:
+		// we only want to check if a token expired before now if the expiry time is *not zero*;
+		// ie., if it's been explicity set.
+		if !pgt.CodeExpiresAt.IsZero() && pgt.CodeExpiresAt.Before(now) || !pgt.RefreshExpiresAt.IsZero() && pgt.RefreshExpiresAt.Before(now) || !pgt.AccessExpiresAt.IsZero() && pgt.AccessExpiresAt.Before(now) {
+			if err := pts.db.DeleteByID(pgt.ID, &pgt); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+// Create creates and store the new token information.
+// For the original implementation, see https://github.com/gotosocial/oauth2/blob/master/store/token.go#L34
+func (pts *tokenStore) Create(ctx context.Context, info oauth2.TokenInfo) error {
+	t, ok := info.(*models.Token)
+	if !ok {
+		return errors.New("info param was not a models.Token")
+	}
+	if err := pts.db.Put(oauthTokenToPGToken(t)); err != nil {
+		return fmt.Errorf("error in tokenstore create: %s", err)
+	}
+	return nil
+}
+
+// RemoveByCode deletes a token from the DB based on the Code field
+func (pts *tokenStore) RemoveByCode(ctx context.Context, code string) error {
+	return pts.db.DeleteWhere("code", code, &oauthToken{})
+}
+
+// RemoveByAccess deletes a token from the DB based on the Access field
+func (pts *tokenStore) RemoveByAccess(ctx context.Context, access string) error {
+	return pts.db.DeleteWhere("access", access, &oauthToken{})
+}
+
+// RemoveByRefresh deletes a token from the DB based on the Refresh field
+func (pts *tokenStore) RemoveByRefresh(ctx context.Context, refresh string) error {
+	return pts.db.DeleteWhere("refresh", refresh, &oauthToken{})
+}
+
+// GetByCode selects a token from the DB based on the Code field
+func (pts *tokenStore) GetByCode(ctx context.Context, code string) (oauth2.TokenInfo, error) {
+	pgt := &oauthToken{
+		Code: code,
+	}
+	if err := pts.db.GetWhere("code", code, pgt); err != nil {
+		return nil, err
+	}
+	return pgTokenToOauthToken(pgt), nil
+}
+
+// GetByAccess selects a token from the DB based on the Access field
+func (pts *tokenStore) GetByAccess(ctx context.Context, access string) (oauth2.TokenInfo, error) {
+	pgt := &oauthToken{
+		Access: access,
+	}
+	if err := pts.db.GetWhere("access", access, pgt); err != nil {
+		return nil, err
+	}
+	return pgTokenToOauthToken(pgt), nil
+}
+
+// GetByRefresh selects a token from the DB based on the Refresh field
+func (pts *tokenStore) GetByRefresh(ctx context.Context, refresh string) (oauth2.TokenInfo, error) {
+	pgt := &oauthToken{
+		Refresh: refresh,
+	}
+	if err := pts.db.GetWhere("refresh", refresh, pgt); err != nil {
+		return nil, err
+	}
+	return pgTokenToOauthToken(pgt), nil
+}
+
+/*
+	The following models are basically helpers for the postgres token store implementation, they should only be used internally.
+*/
+
+// oauthToken is a translation of the gotosocial token with the ExpiresIn fields replaced with ExpiresAt.
+//
+// Explanation for this: gotosocial assumes an in-memory or file database of some kind, where a time-to-live parameter (TTL) can be defined,
+// and tokens with expired TTLs are automatically removed. Since Postgres doesn't have that feature, it's easier to set an expiry time and
+// then periodically sweep out tokens when that time has passed.
+//
+// Note that this struct does *not* satisfy the token interface shown here: https://github.com/gotosocial/oauth2/blob/master/model.go#L22
+// and implemented here: https://github.com/gotosocial/oauth2/blob/master/models/token.go.
+// As such, manual translation is always required between oauthToken and the gotosocial *model.Token. The helper functions oauthTokenToPGToken
+// and pgTokenToOauthToken can be used for that.
+type oauthToken struct {
+	ID                  string `pg:"type:uuid,default:gen_random_uuid(),pk,notnull"`
+	ClientID            string
+	UserID              string
+	RedirectURI         string
+	Scope               string
+	Code                string `pg:"default:'',pk"`
+	CodeChallenge       string
+	CodeChallengeMethod string
+	CodeCreateAt        time.Time `pg:"type:timestamp"`
+	CodeExpiresAt       time.Time `pg:"type:timestamp"`
+	Access              string    `pg:"default:'',pk"`
+	AccessCreateAt      time.Time `pg:"type:timestamp"`
+	AccessExpiresAt     time.Time `pg:"type:timestamp"`
+	Refresh             string    `pg:"default:'',pk"`
+	RefreshCreateAt     time.Time `pg:"type:timestamp"`
+	RefreshExpiresAt    time.Time `pg:"type:timestamp"`
+}
+
+// oauthTokenToPGToken is a lil util function that takes a gotosocial token and gives back a token for inserting into postgres
+func oauthTokenToPGToken(tkn *models.Token) *oauthToken {
+	now := time.Now()
+
+	// For the following, we want to make sure we're not adding a time.Now() to an *empty* ExpiresIn, otherwise that's
+	// going to cause all sorts of interesting problems. So check first to make sure that the ExpiresIn is not equal
+	// to the zero value of a time.Duration, which is 0s. If it *is* empty/nil, just leave the ExpiresAt at nil as well.
+
+	var cea time.Time
+	if tkn.CodeExpiresIn != 0*time.Second {
+		cea = now.Add(tkn.CodeExpiresIn)
+	}
+
+	var aea time.Time
+	if tkn.AccessExpiresIn != 0*time.Second {
+		aea = now.Add(tkn.AccessExpiresIn)
+	}
+
+	var rea time.Time
+	if tkn.RefreshExpiresIn != 0*time.Second {
+		rea = now.Add(tkn.RefreshExpiresIn)
+	}
+
+	return &oauthToken{
+		ClientID:            tkn.ClientID,
+		UserID:              tkn.UserID,
+		RedirectURI:         tkn.RedirectURI,
+		Scope:               tkn.Scope,
+		Code:                tkn.Code,
+		CodeChallenge:       tkn.CodeChallenge,
+		CodeChallengeMethod: tkn.CodeChallengeMethod,
+		CodeCreateAt:        tkn.CodeCreateAt,
+		CodeExpiresAt:       cea,
+		Access:              tkn.Access,
+		AccessCreateAt:      tkn.AccessCreateAt,
+		AccessExpiresAt:     aea,
+		Refresh:             tkn.Refresh,
+		RefreshCreateAt:     tkn.RefreshCreateAt,
+		RefreshExpiresAt:    rea,
+	}
+}
+
+// pgTokenToOauthToken is a lil util function that takes a postgres token and gives back a gotosocial token
+func pgTokenToOauthToken(pgt *oauthToken) *models.Token {
+	now := time.Now()
+
+	return &models.Token{
+		ClientID:            pgt.ClientID,
+		UserID:              pgt.UserID,
+		RedirectURI:         pgt.RedirectURI,
+		Scope:               pgt.Scope,
+		Code:                pgt.Code,
+		CodeChallenge:       pgt.CodeChallenge,
+		CodeChallengeMethod: pgt.CodeChallengeMethod,
+		CodeCreateAt:        pgt.CodeCreateAt,
+		CodeExpiresIn:       pgt.CodeExpiresAt.Sub(now),
+		Access:              pgt.Access,
+		AccessCreateAt:      pgt.AccessCreateAt,
+		AccessExpiresIn:     pgt.AccessExpiresAt.Sub(now),
+		Refresh:             pgt.Refresh,
+		RefreshCreateAt:     pgt.RefreshCreateAt,
+		RefreshExpiresIn:    pgt.RefreshExpiresAt.Sub(now),
+	}
+}