Add helper wrapper for handlers that require signed in state, to reduce boilerplate.

app/app.go

@@ -15,6 +15,7 @@ import (
 	"appengine"
 
 	"github.com/google/go-github/github"
+	"github.com/gorilla/sessions"
 )
 
 const (
@@ -32,6 +33,36 @@ type AppError struct {
 	Type    int
 }
 
+type AppSignedInState struct {
+	Account        *Account
+	GitHubClient   *github.Client
+	session        *sessions.Session
+	request        *http.Request
+	responseWriter http.ResponseWriter
+}
+
+func (state *AppSignedInState) AddFlash(value interface{}) {
+	state.session.AddFlash(value)
+	state.saveSession()
+}
+
+func (state *AppSignedInState) Flashes() []interface{} {
+	flashes := state.session.Flashes()
+	if len(flashes) > 0 {
+		state.saveSession()
+	}
+	return flashes
+}
+
+func (state *AppSignedInState) ClearSession() {
+	state.session.Options.MaxAge = -1
+	state.saveSession()
+}
+
+func (state *AppSignedInState) saveSession() {
+	state.session.Save(state.request, state.responseWriter)
+}
+
 func GitHubFetchError(err error, fetchType string) *AppError {
 	return &AppError{
 		Error:   err,
@@ -84,6 +115,10 @@ func RedirectToRoute(routeName string) *AppError {
 	return RedirectToUrl(routeUrl.String())
 }
 
+func NotSignedIn() *AppError {
+	return RedirectToRoute("index")
+}
+
 type AppHandler func(http.ResponseWriter, *http.Request) *AppError
 
 func (fn AppHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
@@ -92,6 +127,39 @@ func (fn AppHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
+type SignedInAppHandler func(http.ResponseWriter, *http.Request, *AppSignedInState) *AppError
+
+func (fn SignedInAppHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	session, _ := sessionStore.Get(r, sessionConfig.CookieName)
+	userId, ok := session.Values[sessionConfig.UserIdKey].(int)
+	if !ok {
+		handleAppError(NotSignedIn(), w, r)
+		return
+	}
+	c := appengine.NewContext(r)
+	account, err := getAccount(c, userId)
+	if account == nil || err != nil {
+		handleAppError(NotSignedIn(), w, r)
+		return
+	}
+
+	oauthTransport := githubOAuthTransport(c)
+	oauthTransport.Token = &account.OAuthToken
+	githubClient := github.NewClient(oauthTransport.Client())
+
+	state := &AppSignedInState{
+		Account:        account,
+		GitHubClient:   githubClient,
+		session:        session,
+		responseWriter: w,
+		request:        r,
+	}
+
+	if e := fn(w, r, state); e != nil {
+		handleAppError(e, w, r)
+	}
+}
+
 func handleAppError(e *AppError, w http.ResponseWriter, r *http.Request) {
 	c := appengine.NewContext(r)
 	if e.Type == AppErrorTypeGitHubFetch {

app/retrogit.go

@@ -46,14 +46,14 @@ func init() {
 	router.Handle("/session/sign-out", AppHandler(signOutHandler)).Name("sign-out").Methods("POST")
 	router.Handle("/github/callback", AppHandler(githubOAuthCallbackHandler))
 
-	router.Handle("/digest/view", AppHandler(viewDigestHandler)).Name("view-digest")
+	router.Handle("/digest/view", SignedInAppHandler(viewDigestHandler)).Name("view-digest")
-	router.Handle("/digest/send", AppHandler(sendDigestHandler)).Name("send-digest").Methods("POST")
+	router.Handle("/digest/send", SignedInAppHandler(sendDigestHandler)).Name("send-digest").Methods("POST")
 	router.Handle("/digest/cron", AppHandler(digestCronHandler))
 
-	router.Handle("/account/settings", AppHandler(settingsHandler)).Name("settings").Methods("GET")
+	router.Handle("/account/settings", SignedInAppHandler(settingsHandler)).Name("settings").Methods("GET")
-	router.Handle("/account/settings", AppHandler(saveSettingsHandler)).Name("save-settings").Methods("POST")
+	router.Handle("/account/settings", SignedInAppHandler(saveSettingsHandler)).Name("save-settings").Methods("POST")
-	router.Handle("/account/set-initial-timezone", AppHandler(setInitialTimezoneHandler)).Name("set-initial-timezone").Methods("POST")
+	router.Handle("/account/set-initial-timezone", SignedInAppHandler(setInitialTimezoneHandler)).Name("set-initial-timezone").Methods("POST")
-	router.Handle("/account/delete", AppHandler(deleteAccountHandler)).Name("delete-account").Methods("POST")
+	router.Handle("/account/delete", SignedInAppHandler(deleteAccountHandler)).Name("delete-account").Methods("POST")
 
 	router.Handle("/admin/users", AppHandler(usersAdminHandler))
 	router.Handle("/admin/digest", AppHandler(digestAdminHandler)).Name("digest-admin")
@@ -183,20 +183,9 @@ func signOutHandler(w http.ResponseWriter, r *http.Request) *AppError {
 	return RedirectToRoute("index")
 }
 
-func viewDigestHandler(w http.ResponseWriter, r *http.Request) *AppError {
+func viewDigestHandler(w http.ResponseWriter, r *http.Request, state *AppSignedInState) *AppError {
-	session, _ := sessionStore.Get(r, sessionConfig.CookieName)
-	userId := session.Values[sessionConfig.UserIdKey].(int)
 	c := appengine.NewContext(r)
-	account, err := getAccount(c, userId)
+	digest, err := newDigest(c, state.GitHubClient, state.Account)
-	if err != nil {
-		return InternalError(err, "Could not look up account")
-	}
-
-	oauthTransport := githubOAuthTransport(c)
-	oauthTransport.Token = &account.OAuthToken
-	githubClient := github.NewClient(oauthTransport.Client())
-
-	digest, err := newDigest(c, githubClient, account)
 	if err != nil {
 		return GitHubFetchError(err, "digest")
 	}
@@ -206,26 +195,18 @@ func viewDigestHandler(w http.ResponseWriter, r *http.Request) *AppError {
 	return templates["digest-page"].Render(w, data)
 }
 
-func sendDigestHandler(w http.ResponseWriter, r *http.Request) *AppError {
+func sendDigestHandler(w http.ResponseWriter, r *http.Request, state *AppSignedInState) *AppError {
-	session, _ := sessionStore.Get(r, sessionConfig.CookieName)
-	userId := session.Values[sessionConfig.UserIdKey].(int)
 	c := appengine.NewContext(r)
-	account, err := getAccount(c, userId)
+	sent, err := sendDigestForAccount(state.Account, c)
-	if err != nil {
-		return InternalError(err, "Could not look up account")
-	}
-
-	sent, err := sendDigestForAccount(account, c)
 	if err != nil {
 		return InternalError(err, "Could not send digest")
 	}
 
 	if sent {
-		session.AddFlash("Digest emailed!")
+		state.AddFlash("Digest emailed!")
 	} else {
-		session.AddFlash("No digest was sent, it was empty or disabled.")
+		state.AddFlash("No digest was sent, it was empty or disabled.")
 	}
-	session.Save(r, w)
 	return RedirectToRoute("index")
 }
 
@@ -346,31 +327,19 @@ func githubOAuthCallbackHandler(w http.ResponseWriter, r *http.Request) *AppErro
 	return RedirectToUrl(continueUrl)
 }
 
-func settingsHandler(w http.ResponseWriter, r *http.Request) *AppError {
+func settingsHandler(w http.ResponseWriter, r *http.Request, state *AppSignedInState) *AppError {
-	session, _ := sessionStore.Get(r, sessionConfig.CookieName)
-	userId := session.Values[sessionConfig.UserIdKey].(int)
 	c := appengine.NewContext(r)
-	account, err := getAccount(c, userId)
+	user, _, err := state.GitHubClient.Users.Get("")
-	if err != nil {
-		// TODO: redirect to sign in again
-		return InternalError(err, "Could not look up account")
-	}
-
-	oauthTransport := githubOAuthTransport(c)
-	oauthTransport.Token = &account.OAuthToken
-	githubClient := github.NewClient(oauthTransport.Client())
-
-	user, _, err := githubClient.Users.Get("")
 	if err != nil {
 		return GitHubFetchError(err, "user")
 	}
 
-	repos, err := getRepos(c, githubClient, account, user)
+	repos, err := getRepos(c, state.GitHubClient, state.Account, user)
 	if err != nil {
 		return GitHubFetchError(err, "repositories")
 	}
 
-	emails, _, err := githubClient.Users.ListEmails(nil)
+	emails, _, err := state.GitHubClient.Users.ListEmails(nil)
 	if err != nil {
 		return GitHubFetchError(err, "emails")
 	}
@@ -378,18 +347,15 @@ func settingsHandler(w http.ResponseWriter, r *http.Request) *AppError {
 	for i := range emails {
 		emailAddresses[i] = *emails[i].Email
 	}
-	accountEmailAddress, err := account.GetDigestEmailAddress(githubClient)
+	accountEmailAddress, err := state.Account.GetDigestEmailAddress(state.GitHubClient)
 	if err != nil {
 		return GitHubFetchError(err, "emails")
 	}
 
-	flashes := session.Flashes()
+	flashes := state.Flashes()
-	if len(flashes) > 0 {
-		session.Save(r, w)
-	}
 
 	var data = map[string]interface{}{
-		"Account":             account,
+		"Account":             state.Account,
 		"User":                user,
 		"Timezones":           timezones,
 		"Repos":               repos,
@@ -400,25 +366,16 @@ func settingsHandler(w http.ResponseWriter, r *http.Request) *AppError {
 	return templates["settings"].Render(w, data)
 }
 
-func saveSettingsHandler(w http.ResponseWriter, r *http.Request) *AppError {
+func saveSettingsHandler(w http.ResponseWriter, r *http.Request, state *AppSignedInState) *AppError {
-	session, _ := sessionStore.Get(r, sessionConfig.CookieName)
-	userId := session.Values[sessionConfig.UserIdKey].(int)
 	c := appengine.NewContext(r)
-	account, err := getAccount(c, userId)
+	account := state.Account
-	if err != nil {
-		// TODO: redirect to sign in again
-		return InternalError(err, "Could not look up account")
-	}
-	oauthTransport := githubOAuthTransport(c)
-	oauthTransport.Token = &account.OAuthToken
-	githubClient := github.NewClient(oauthTransport.Client())
 
-	user, _, err := githubClient.Users.Get("")
+	user, _, err := state.GitHubClient.Users.Get("")
 	if err != nil {
 		return GitHubFetchError(err, "user")
 	}
 
-	repos, err := getRepos(c, githubClient, account, user)
+	repos, err := getRepos(c, state.GitHubClient, account, user)
 	if err != nil {
 		return GitHubFetchError(err, "repos")
 	}
@@ -453,23 +410,16 @@ func saveSettingsHandler(w http.ResponseWriter, r *http.Request) *AppError {
 		return InternalError(err, "Could not save user")
 	}
 
-	session.AddFlash("Settings saved.")
+	state.AddFlash("Settings saved.")
-	session.Save(r, w)
 	return RedirectToRoute("settings")
 }
 
-func setInitialTimezoneHandler(w http.ResponseWriter, r *http.Request) *AppError {
+func setInitialTimezoneHandler(w http.ResponseWriter, r *http.Request, state *AppSignedInState) *AppError {
-	session, _ := sessionStore.Get(r, sessionConfig.CookieName)
-	userId := session.Values[sessionConfig.UserIdKey].(int)
 	c := appengine.NewContext(r)
-	account, err := getAccount(c, userId)
+	account := state.Account
-	if err != nil {
-		// TODO: redirect to sign in again
-		return InternalError(err, "Could not look up account")
-	}
 
 	timezoneName := r.FormValue("timezone_name")
-	_, err = time.LoadLocation(timezoneName)
+	_, err := time.LoadLocation(timezoneName)
 	if err != nil {
 		return BadRequest(err, "Malformed timezone_name value")
 	}
@@ -512,21 +462,10 @@ var cacheDigestForAccountFunc = delay.Func(
 		return nil
 	})
 
-func deleteAccountHandler(w http.ResponseWriter, r *http.Request) *AppError {
+func deleteAccountHandler(w http.ResponseWriter, r *http.Request, state *AppSignedInState) *AppError {
-	session, _ := sessionStore.Get(r, sessionConfig.CookieName)
-	userId := session.Values[sessionConfig.UserIdKey].(int)
 	c := appengine.NewContext(r)
-	account, err := getAccount(c, userId)
+	state.Account.Delete(c)
-	if err != nil {
+	state.ClearSession()
-		// TODO: redirect to sign in again
-		return InternalError(err, "Could not look up account")
-	}
-
-	account.Delete(c)
-	session.Options.MaxAge = -1
-	session.Save(r, w)
-
-	// TODO: add a flash message saying that the account was deleted.
 	return RedirectToRoute("index")
 }