added registeration and started user login

web/forms.go

@@ -6,6 +6,8 @@ func init() {
 	gob.Register(CreatePostForm{})
 	gob.Register(CreateThreadForm{})
 	gob.Register(CreateCommentForm{})
+	gob.Register(RegisterForm{})
+	gob.Register(LoginForm{})
 	gob.Register(FormErrors{})
 }
 
@@ -66,3 +68,53 @@ func (f *CreateCommentForm) Validate() bool {
 
 	return len(f.Errors) == 0
 }
+
+type RegisterForm struct {
+	Username      string
+	Password      string
+	UsernameTaken bool
+
+	Errors FormErrors
+}
+
+func (f *RegisterForm) Validate() bool {
+	f.Errors = FormErrors{}
+
+	if f.Username == "" {
+		f.Errors["Username"] = "Please enter a username!"
+	} else if f.UsernameTaken {
+		f.Errors["Username"] = "This username is already taken!"
+	}
+
+	if f.Password == "" {
+		f.Errors["Password"] = "Please enter a password!"
+	} else if len(f.Password) < 8 {
+		f.Errors["Password"] = "Your password must be at least 8 charachters long."
+	}
+
+	return len(f.Errors) == 0
+}
+
+type LoginForm struct {
+	Username             string
+	Password             string
+	IncorrectCredentials bool
+
+	Errors FormErrors
+}
+
+func (f *LoginForm) Validate() bool {
+	f.Errors = FormErrors{}
+
+	if f.Username == "" {
+		f.Errors["Username"] = "Please enter a username!"
+	} else if f.IncorrectCredentials {
+		f.Errors["Username"] = "Username or password is incorrect."
+	}
+
+	if f.Password == "" {
+		f.Errors["Password"] = "Please enter a password!"
+	}
+
+	return len(f.Errors) == 0
+}

web/handler.go

@@ -22,6 +22,7 @@ func NewHandler(store goddit.Store, sessions *scs.SessionManager, csrfKey []byte
 	threads := ThreadHandler{store: store, sessions: sessions}
 	posts := PostHandler{store: store, sessions: sessions}
 	comments := CommentHandler{store: store, sessions: sessions}
+	users := UserHandler{store: store, sessions: sessions}
 
 	h.Use(middleware.Logger)
 	h.Use(csrf.Protect(csrfKey, csrf.Secure(false)))
@@ -41,6 +42,11 @@ func NewHandler(store goddit.Store, sessions *scs.SessionManager, csrfKey []byte
 		r.Post("/{threadID}/{postID}", comments.Store())
 	})
 	h.Get("/comments/{id}/vote", comments.Vote())
+	h.Get("/register", users.Register())
+	h.Post("/register", users.RegisterSubmit())
+	h.Get("/login", users.Login())
+	h.Post("/login", users.LoginSubmit())
+	h.Get("/logout", users.Logout())
 
 	return h
 }
@@ -70,7 +76,7 @@ func (h *Handler) Home() http.HandlerFunc {
 		}
 
 		once.Do(func() {
-			h.sessions.Put(r.Context(), "flash", "hello")
+			h.sessions.Put(r.Context(), "flash", "helloc")
 		})
 
 		tmpl.Execute(w, data{

web/sessions.go

@@ -3,11 +3,17 @@ package web
 import (
 	"context"
 	"database/sql"
+	"encoding/gob"
 
 	"github.com/alexedwards/scs/postgresstore"
 	"github.com/alexedwards/scs/v2"
+	"github.com/google/uuid"
 )
 
+func init() {
+	gob.Register(uuid.UUID{})
+}
+
 func NewSessionsManager(dataSourceName string) (*scs.SessionManager, error) {
 	db, err := sql.Open("postgres", dataSourceName)
 	if err != nil {

web/user_handler.go

@@ -0,0 +1,117 @@
+package web
+
+import (
+	"html/template"
+	"net/http"
+
+	"git.snrd.de/Spaenny/goddit"
+	"github.com/alexedwards/scs/v2"
+	"github.com/google/uuid"
+	"github.com/gorilla/csrf"
+	"golang.org/x/crypto/bcrypt"
+)
+
+type UserHandler struct {
+	store    goddit.Store
+	sessions *scs.SessionManager
+}
+
+func (h *UserHandler) Register() http.HandlerFunc {
+	type data struct {
+		SessionData
+
+		CSRF template.HTML
+	}
+	tmpl := template.Must(template.ParseFiles("templates/layout.html", "templates/user_register.html"))
+	return func(w http.ResponseWriter, r *http.Request) {
+		tmpl.Execute(w, data{
+			SessionData: GetSessionData(h.sessions, r.Context()),
+			CSRF:        csrf.TemplateField(r),
+		})
+	}
+}
+
+func (h *UserHandler) RegisterSubmit() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		form := RegisterForm{
+			Username:      r.FormValue("username"),
+			Password:      r.FormValue("password"),
+			UsernameTaken: false,
+		}
+		if _, err := h.store.UserByUsername(form.Username); err == nil {
+			form.UsernameTaken = true
+		}
+		if !form.Validate() {
+			h.sessions.Put(r.Context(), "form", form)
+			http.Redirect(w, r, r.Referer(), http.StatusFound)
+			return
+		}
+
+		password, err := bcrypt.GenerateFromPassword([]byte(form.Password), bcrypt.DefaultCost)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		if err := h.store.CreateUser(&goddit.User{
+			ID:       uuid.New(),
+			Username: form.Username,
+			Password: string(password),
+		}); err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		h.sessions.Put(r.Context(), "flash", "Your registration was successful. Please log in.")
+		http.Redirect(w, r, "/", http.StatusFound)
+	}
+}
+
+func (h *UserHandler) Login() http.HandlerFunc {
+	type data struct {
+		SessionData
+
+		CSRF template.HTML
+	}
+	tmpl := template.Must(template.ParseFiles("templates/layout.html", "templates/user_login.html"))
+	return func(w http.ResponseWriter, r *http.Request) {
+		tmpl.Execute(w, data{
+			SessionData: GetSessionData(h.sessions, r.Context()),
+			CSRF:        csrf.TemplateField(r),
+		})
+	}
+}
+
+func (h *UserHandler) LoginSubmit() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		form := LoginForm{
+			Username:             r.FormValue("username"),
+			Password:             r.FormValue("password"),
+			IncorrectCredentials: false,
+		}
+		user, err := h.store.UserByUsername(form.Username)
+		if err == nil {
+			form.IncorrectCredentials = true
+		} else {
+			compareErr := bcrypt.CompareHashAndPassword([]byte(user.Password), []byte(form.Password))
+			form.IncorrectCredentials = compareErr != nil
+		}
+		if !form.Validate() {
+			h.sessions.Put(r.Context(), "form", form)
+			http.Redirect(w, r, r.Referer(), http.StatusFound)
+			return
+		}
+
+		h.sessions.Put(r.Context(), "user_id", user.ID)
+		h.sessions.Put(r.Context(), "flash", "You have been logged in successfully.")
+		http.Redirect(w, r, "/", http.StatusFound)
+	}
+}
+
+func (h *UserHandler) Logout() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		h.sessions.Remove(r.Context(), "user_id")
+		h.sessions.Put(r.Context(), "flash", "You have been logged out successfully.")
+		http.Redirect(w, r, "/", http.StatusFound)
+	}
+}