Add Homepage, login, signup page UI. Add logout functionality

cmd/main.go

@@ -37,9 +37,16 @@ func main() {
 	mux := http.NewServeMux()
 
 	// Routes
-	mux.HandleFunc("/login", handler.LoginHandler)
+	mux.Handle("GET /static/", http.StripPrefix("/static/", http.FileServer(http.Dir("./ui/static"))))
+
+	mux.HandleFunc("GET /{$}", handler.HomeHandler)
+	mux.HandleFunc("GET /login", handler.LoginPageHandler)
 	mux.HandleFunc("/user", handler.UserHandler)
-	mux.HandleFunc("/signup", handler.SignUpHandler)
+	mux.HandleFunc("/signup", handler.SignUpPageHandler)
+
+	mux.HandleFunc("POST /api/login", handler.LoginHandler)
+	mux.HandleFunc("POST /api/logout", handler.LogoutHandler)
+	mux.HandleFunc("POST /api/signup", handler.SignUpHandler)
 
 	// Apply middleware (CORS first, then logging)
 	muxMiddleware := handlers.LoggingMiddleware(handlers.CORSMiddleware(mux))

internal/auth/session.go

@@ -37,20 +37,3 @@ func HashSecret(secret string) []byte {
 func CheckExpiration(expirarion time.Time) bool {
 	return time.Since(expirarion).Seconds() >= sessionExpiresInSeconds
 }
-
-func ParseCookies(cookieHeader string) map[string]string {
-	cookies := make(map[string]string)
-	if cookieHeader == "" {
-		return cookies
-	}
-
-	pairs := strings.Split(cookieHeader, ";")
-	for _, pair := range pairs {
-		pair = strings.TrimSpace(pair)
-		parts := strings.SplitN(pair, "=", 2)
-		if len(parts) == 2 {
-			cookies[parts[0]] = parts[1]
-		}
-	}
-	return cookies
-}

internal/handlers/handler.go

@@ -4,6 +4,9 @@ import (
 	"context"
 	"go-backend/internal/database/sqlc"
 	"go-backend/internal/services"
+	"log"
+	"net/http"
+	"text/template"
 )
 
 // UserService and AuthService are defined here, on the consumer side, so
@@ -19,6 +22,7 @@ type UserService interface {
 type AuthService interface {
 	CreateSession(ctx context.Context, userID string) (*services.SessionWithToken, error)
 	ValidateSessionToken(ctx context.Context, token string) (*sqlc.UserSession, error)
+	DeleteSession(ctx context.Context, token string) error
 }
 
 type Handler struct {
@@ -32,3 +36,117 @@ func NewHandler(users UserService, auth AuthService) *Handler {
 		auth:  auth,
 	}
 }
+
+func (h *Handler) HomeHandler(w http.ResponseWriter, r *http.Request) {
+	cookie, err := r.Cookie("session")
+
+	if err != nil {
+		http.Redirect(w, r, "/login", http.StatusSeeOther)
+		return
+	}
+
+	session, err := h.auth.ValidateSessionToken(r.Context(), cookie.Value)
+
+	if err != nil {
+		log.Print(err.Error())
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	if session == nil {
+		http.Redirect(w, r, "/login", http.StatusSeeOther)
+		return
+	}
+
+	files := []string{
+		"./ui/html/base.tmpl",
+		"./ui/html/pages/index.tmpl",
+	}
+
+	ts, err := template.ParseFiles(files...)
+	if err != nil {
+		log.Print(err.Error())
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	err = ts.ExecuteTemplate(w, "base", nil)
+	if err != nil {
+		log.Print(err.Error())
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+	}
+}
+
+func (h *Handler) LoginPageHandler(w http.ResponseWriter, r *http.Request) {
+	cookie, err := r.Cookie("session")
+
+	if cookie != nil {
+		session, err := h.auth.ValidateSessionToken(r.Context(), cookie.Value)
+
+		if err != nil {
+			log.Print(err.Error())
+			http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+			return
+		}
+
+		if session != nil {
+			http.Redirect(w, r, "/", http.StatusSeeOther)
+			return
+		}
+	}
+
+	files := []string{
+		"./ui/html/base.tmpl",
+		"./ui/html/pages/login.tmpl",
+	}
+
+	ts, err := template.ParseFiles(files...)
+	if err != nil {
+		log.Print(err.Error())
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	err = ts.ExecuteTemplate(w, "base", nil)
+	if err != nil {
+		log.Print(err.Error())
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+	}
+}
+
+func (h *Handler) SignUpPageHandler(w http.ResponseWriter, r *http.Request) {
+	cookie, err := r.Cookie("session")
+
+	if cookie != nil {
+		session, err := h.auth.ValidateSessionToken(r.Context(), cookie.Value)
+
+		if err != nil {
+			log.Print(err.Error())
+			http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+			return
+		}
+
+		if session != nil {
+			http.Redirect(w, r, "/", http.StatusSeeOther)
+			return
+		}
+	}
+
+	files := []string{
+		"./ui/html/base.tmpl",
+		"./ui/html/pages/signup.tmpl",
+	}
+
+	ts, err := template.ParseFiles(files...)
+	if err != nil {
+		log.Print(err.Error())
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	err = ts.ExecuteTemplate(w, "base", nil)
+	if err != nil {
+		log.Print(err.Error())
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+	}
+}

internal/handlers/login.go

@@ -1,7 +1,6 @@
 package handlers
 
 import (
-	"encoding/json"
 	"log"
 	"net/http"
 
@@ -9,23 +8,19 @@ import (
 )
 
 type LoginRequest struct {
-	Username string `json:"username"`
-	Password string `json:"password"`
+	Username string
+	Password string
 }
 
 func (h *Handler) LoginHandler(w http.ResponseWriter, r *http.Request) {
-	if r.Method != http.MethodPost {
-		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+	if err := r.ParseForm(); err != nil {
+		http.Error(w, "Invalid request body", http.StatusBadRequest)
 		return
 	}
 
-	var req LoginRequest
-
-	decoder := json.NewDecoder(r.Body)
-	err := decoder.Decode(&req)
-	if err != nil {
-		http.Error(w, "Invalid request body", http.StatusBadRequest)
-		return
+	req := LoginRequest{
+		Username: r.PostFormValue("username"),
+		Password: r.PostFormValue("password"),
 	}
 
 	if req.Username == "" || req.Password == "" {
@@ -67,6 +62,38 @@ func (h *Handler) LoginHandler(w http.ResponseWriter, r *http.Request) {
 	}
 	http.SetCookie(w, cookie)
 
+	w.Header().Set("HX-Redirect", "/")
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte("Success"))
+}
+
+func (h *Handler) LogoutHandler(w http.ResponseWriter, r *http.Request) {
+	cookie, err := r.Cookie("session")
+
+	if err != nil {
+		http.Error(w, "Unauthorized", http.StatusUnauthorized)
+		return
+	}
+
+	err = h.auth.DeleteSession(r.Context(), cookie.Value)
+
+	if err != nil {
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	cookie = &http.Cookie{
+		Name:     "session",
+		Value:    "",
+		HttpOnly: true,
+		SameSite: http.SameSiteLaxMode,
+		MaxAge:   -1,
+		Path:     "/",
+	}
+
+	http.SetCookie(w, cookie)
+
+	w.Header().Set("HX-Redirect", "/")
 	w.WriteHeader(http.StatusOK)
 	w.Write([]byte("Success"))
 }

internal/handlers/login_test.go

@@ -1,161 +0,0 @@
-package handlers
-
-import (
-	"bytes"
-	"encoding/base64"
-	"errors"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	"go-backend/internal/auth"
-	"go-backend/internal/database"
-	"go-backend/internal/services"
-
-	"golang.org/x/crypto/argon2"
-)
-
-// fakeUsers and fakeAuth satisfy the UserService and AuthService interfaces
-// declared in handler.go. No database, no network, no real hashing work —
-// each test controls exactly what the "service layer" returns.
-
-type fakeUsers struct {
-	user *database.User
-	err  error
-}
-
-func (f *fakeUsers) FindByUsername(username string) (*database.User, error) {
-	return f.user, f.err
-}
-
-func (f *fakeUsers) FindByID(id string) (*database.User, error) {
-	return f.user, f.err
-}
-
-type fakeAuth struct {
-	session *services.SessionWithToken
-	err     error
-}
-
-func (f *fakeAuth) CreateSession(userID string) (*auth.SessionWithToken, error) {
-	return f.session, f.err
-}
-
-func (f *fakeAuth) ValidateSessionToken(token string) (*auth.Session, error) {
-	return nil, nil
-}
-
-// hashPassword builds a real Argon2id hash in the format auth.VerifyPassword
-// expects, so the "correct password" test case exercises the real
-// verification logic rather than a stub.
-func hashPassword(password, salt string) string {
-	saltBytes := []byte(salt)
-	hash := argon2.IDKey([]byte(password), saltBytes, 3, 65536, 4, 32)
-	return "$argon2id$v=19$m=65536,t=3,p=4$" +
-		base64.RawStdEncoding.EncodeToString(saltBytes) + "$" +
-		base64.RawStdEncoding.EncodeToString(hash)
-}
-
-func TestLoginHandler(t *testing.T) {
-	validUser := &database.User{ID: "user-1", Username: "alice", PasswordHash: hashPassword("correct-horse", "somesalt16bytes!")}
-
-	tests := []struct {
-		name       string
-		body       string
-		users      UserService
-		auth       AuthService
-		wantStatus int
-	}{
-		{
-			name:       "successful login sets session cookie",
-			body:       `{"username":"alice","password":"correct-horse"}`,
-			users:      &fakeUsers{user: validUser},
-			auth:       &fakeAuth{session: &services.SessionWithToken{Token: "abc.def"}},
-			wantStatus: http.StatusOK,
-		},
-		{
-			name:       "wrong password rejected",
-			body:       `{"username":"alice","password":"wrong-password"}`,
-			users:      &fakeUsers{user: validUser},
-			auth:       &fakeAuth{},
-			wantStatus: http.StatusBadRequest,
-		},
-		{
-			name:       "unknown username rejected",
-			body:       `{"username":"nobody","password":"whatever"}`,
-			users:      &fakeUsers{user: nil},
-			auth:       &fakeAuth{},
-			wantStatus: http.StatusBadRequest,
-		},
-		{
-			name:       "missing fields rejected before hitting services",
-			body:       `{"username":"","password":""}`,
-			users:      &fakeUsers{err: errors.New("should never be called")},
-			auth:       &fakeAuth{},
-			wantStatus: http.StatusBadRequest,
-		},
-		{
-			name:       "user lookup failure returns 500",
-			body:       `{"username":"alice","password":"correct-horse"}`,
-			users:      &fakeUsers{err: errors.New("connection refused")},
-			auth:       &fakeAuth{},
-			wantStatus: http.StatusInternalServerError,
-		},
-		{
-			name:       "session creation failure returns 500",
-			body:       `{"username":"alice","password":"correct-horse"}`,
-			users:      &fakeUsers{user: validUser},
-			auth:       &fakeAuth{err: errors.New("disk full")},
-			wantStatus: http.StatusInternalServerError,
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			h := NewHandler(tt.users, tt.auth)
-
-			req := httptest.NewRequest(http.MethodPost, "/login", bytes.NewBufferString(tt.body))
-			w := httptest.NewRecorder()
-
-			h.LoginHandler(w, req)
-
-			if w.Code != tt.wantStatus {
-				t.Fatalf("status = %d, want %d (body: %s)", w.Code, tt.wantStatus, w.Body.String())
-			}
-
-			if tt.wantStatus == http.StatusOK {
-				resp := w.Result()
-				cookies := resp.Cookies()
-				if len(cookies) != 1 || cookies[0].Name != "session" || cookies[0].Value != "abc.def" {
-					t.Fatalf("expected session cookie with token abc.def, got %+v", cookies)
-				}
-			}
-		})
-	}
-}
-
-func TestLoginHandlerRejectsInvalidJSON(t *testing.T) {
-	h := NewHandler(&fakeUsers{}, &fakeAuth{})
-
-	req := httptest.NewRequest(http.MethodPost, "/login", bytes.NewBufferString(`not-json`))
-	w := httptest.NewRecorder()
-
-	h.LoginHandler(w, req)
-
-	if w.Code != http.StatusBadRequest {
-		t.Fatalf("status = %d, want %d", w.Code, http.StatusBadRequest)
-	}
-}
-
-func TestLoginHandlerRejectsWrongMethod(t *testing.T) {
-	h := NewHandler(&fakeUsers{}, &fakeAuth{})
-
-	req := httptest.NewRequest(http.MethodGet, "/login", nil)
-	w := httptest.NewRecorder()
-
-	h.LoginHandler(w, req)
-
-	if w.Code != http.StatusMethodNotAllowed {
-		t.Fatalf("status = %d, want %d", w.Code, http.StatusMethodNotAllowed)
-	}
-}

internal/handlers/signup.go

@@ -1,17 +1,16 @@
 package handlers
 
 import (
-	"encoding/json"
 	"go-backend/internal/auth"
 	"go-backend/internal/database/sqlc"
 	"log"
 	"net/http"
 )
 
-type SignUpRequest struct {
-	Username string `json:"username"`
-	Password string `json:"password"`
-	Email    string `json:"email"`
+type SignupRequest struct {
+	Username string
+	Password string
+	Email    string
 }
 
 func (h *Handler) SignUpHandler(w http.ResponseWriter, r *http.Request) {
@@ -20,13 +19,10 @@ func (h *Handler) SignUpHandler(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	var req SignUpRequest
-
-	decoder := json.NewDecoder(r.Body)
-	err := decoder.Decode(&req)
-	if err != nil {
-		http.Error(w, "Invalid request body", http.StatusBadRequest)
-		return
+	req := SignupRequest{
+		Username: r.PostFormValue("username"),
+		Password: r.PostFormValue("password"),
+		Email:    r.PostFormValue("email"),
 	}
 
 	if req.Username == "" || req.Password == "" || req.Email == "" {
@@ -78,6 +74,7 @@ func (h *Handler) SignUpHandler(w http.ResponseWriter, r *http.Request) {
 	}
 	http.SetCookie(w, cookie)
 
+	w.Header().Set("HX-Redirect", "/")
 	w.WriteHeader(http.StatusOK)
 	w.Write([]byte("Success"))
 }

internal/handlers/user.go

@@ -3,8 +3,6 @@ package handlers
 import (
 	"encoding/json"
 	"net/http"
-
-	"go-backend/internal/auth"
 )
 
 type UserResponse struct {
@@ -20,15 +18,14 @@ func (h *Handler) UserHandler(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// Get session token from cookie
-	cookies := auth.ParseCookies(r.Header.Get("Cookie"))
-	sessionToken, exists := cookies["session"]
-	if !exists {
+	cookie, err := r.Cookie("session")
+	if err != nil {
 		http.Error(w, "Unauthorized, no session token", http.StatusUnauthorized)
 		return
 	}
 
 	// Validate session
-	session, err := h.auth.ValidateSessionToken(r.Context(), sessionToken)
+	session, err := h.auth.ValidateSessionToken(r.Context(), cookie.Value)
 	if err != nil {
 		http.Error(w, "Internal server error", http.StatusInternalServerError)
 		return

internal/services/auth.go

@@ -94,3 +94,16 @@ func (s *AuthService) ValidateSessionToken(ctx context.Context, token string) (*
 
 	return &session, nil
 }
+
+func (s *AuthService) DeleteSession(ctx context.Context, token string) error {
+	tokenParts := strings.Split(token, ".")
+	if len(tokenParts) != 2 {
+		return nil
+	}
+
+	sessionID := tokenParts[0]
+
+	err := s.queries.DeleteSessionById(ctx, sessionID)
+
+	return err
+}

ui/html/base.tmpl

@@ -0,0 +1,28 @@
+{{define "base"}}
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <title>{{template "title" .}} - Golang template</title>
+    <!-- Link to the CSS stylesheet and favicon -->
+    <link rel="stylesheet" href="/static/css/main.css" />
+    <link
+      rel="shortcut icon"
+      href="/static/img/favicon.ico"
+      type="image/x-icon"
+    />
+    <!-- Also link to some fonts hosted by Google -->
+    <link
+      rel="stylesheet"
+      href="https://fonts.googleapis.com/css?family=Ubuntu+Mono:400,700"
+    />
+    <script src="https://unpkg.com/htmx.org@1.9.10"></script>
+  </head>
+  <body>
+    <main>{{template "main" .}}</main>
+    <footer>Powered by <a href="https://go.dev/">Go</a></footer>
+    <!-- And include the JavaScript file -->
+    <script src="/static/js/main.js" type="text/javascript"></script>
+  </body>
+</html>
+{{end}}

ui/html/pages/index.tmpl

@@ -0,0 +1,6 @@
+{{define "title"}}Home{{end}}
+
+{{define "main"}}
+    <h1>Welcome</h1>
+    <button hx-post="/api/logout" class="btn">Logout</button>
+{{end}}

ui/html/pages/login.tmpl

@@ -0,0 +1,38 @@
+{{define "title"}}Welcome{{end}}
+
+{{define "main"}}
+    <div class="container">
+      <h1>Log in</h1>
+
+      <form hx-post="/api/login" hx-target="#error-container">
+        <div class="form-group">
+          <div id="error-container" style="color: red; margin-bottom: 10px"></div>
+          <label for="username">Username:</label>
+          <input
+            type="text"
+            id="username"
+            name="username"
+            required
+            minlength="3"
+          />
+        </div>
+
+        <div class="form-group">
+          <label for="password">Password:</label>
+          <input
+            type="password"
+            id="password"
+            name="password"
+            required
+            minlength="6"
+          />
+        </div>
+
+        <button type="submit" class="btn">Login</button>
+      </form>
+
+      <p style="text-align: center; margin-top: 20px">
+        Don't have an account? <a href="/signup">Sign up here</a>
+      </p>
+    </div>
+{{end}}

ui/html/pages/signup.tmpl

@@ -0,0 +1,52 @@
+{{define "title"}}Welcome{{end}}
+
+{{define "main"}}
+    <div class="container">
+      <h1>Register</h1>
+
+      <form hx-post="/api/signup" hx-target="#error-container">
+        <div class="form-group">
+          <div
+            id="error-container"
+            style="color: red; margin-bottom: 10px"
+          ></div>
+          <label for="username">Username:</label>
+          <input
+            type="text"
+            id="username"
+            name="username"
+            required
+            minlength="3"
+          />
+        </div>
+
+        <div class="form-group">
+          <label for="password">Password:</label>
+          <input
+            type="password"
+            id="password"
+            name="password"
+            required
+            minlength="6"
+          />
+        </div>
+
+
+        <div class="form-group">
+          <label for="email">Email:</label>
+          <input
+            type="text"
+            id="email"
+            name="email"
+            required
+          />
+        </div>
+
+        <button type="submit" class="btn">Register</button>
+      </form>
+
+      <p style="text-align: center; margin-top: 20px">
+        Already have an account? <a href="/login">Login here</a>
+      </p>
+    </div>
+{{end}}

ui/static/js/main.js

@@ -0,0 +1,10 @@
+// By default htmx only swaps 2xx/304 responses into hx-target; 4xx/5xx
+// responses are treated as errors and left unswapped. Our API handlers
+// return error status codes with a plain-text body meant for the
+// error-container div, so force the swap to happen anyway.
+document.body.addEventListener("htmx:beforeSwap", function (evt) {
+  if (evt.detail.xhr.status >= 400) {
+    evt.detail.shouldSwap = true;
+    evt.detail.isError = false;
+  }
+});