add SSE

assets/embed.go

@@ -2,5 +2,5 @@ package assets
 
 import "embed"
 
-//go:embed js/* css/*
+//go:embed js/* css/* fonts/*
 var AssetsFS embed.FS

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/alexedwards/argon2id v1.0.0
 	github.com/emersion/go-imap v1.2.1
 	github.com/golang-jwt/jwt/v5 v5.2.2
+	github.com/google/uuid v1.6.0
 	github.com/jackc/pgx/v5 v5.7.6
 	github.com/jmoiron/sqlx v1.4.0
 	github.com/joho/godotenv v1.5.1
@@ -39,7 +40,6 @@ require (
 	github.com/golang-sql/civil v0.0.0-20220223132316-b832511892a9 // indirect
 	github.com/golang-sql/sqlexp v0.1.0 // indirect
 	github.com/golang/protobuf v1.5.3 // indirect
-	github.com/google/uuid v1.6.0 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
 	github.com/jackc/puddle/v2 v2.2.2 // indirect

internal/app/app.go

@@ -5,6 +5,7 @@ import (
 
 	"git.juancwu.dev/juancwu/budgit/internal/config"
 	"git.juancwu.dev/juancwu/budgit/internal/db"
+	"git.juancwu.dev/juancwu/budgit/internal/event"
 	"git.juancwu.dev/juancwu/budgit/internal/repository"
 	"git.juancwu.dev/juancwu/budgit/internal/service"
 	"github.com/jmoiron/sqlx"
@@ -13,6 +14,7 @@ import (
 type App struct {
 	Cfg                 *config.Config
 	DB                  *sqlx.DB
+	EventBus            *event.Broker
 	UserService         *service.UserService
 	AuthService         *service.AuthService
 	EmailService        *service.EmailService
@@ -35,6 +37,8 @@ func New(cfg *config.Config) (*App, error) {
 		return nil, fmt.Errorf("failed to run migrations: %w", err)
 	}
 
+	eventBus := event.NewBroker()
+
 	emailClient := service.NewEmailClient(cfg.MailerSMTPHost, cfg.MailerSMTPPort, cfg.MailerIMAPHost, cfg.MailerIMAPPort, cfg.MailerUsername, cfg.MailerPassword)
 
 	// Repositories
@@ -71,13 +75,14 @@ func New(cfg *config.Config) (*App, error) {
 	)
 	profileService := service.NewProfileService(profileRepository)
 	tagService := service.NewTagService(tagRepository)
-	shoppingListService := service.NewShoppingListService(shoppingListRepository, listItemRepository)
-	expenseService := service.NewExpenseService(expenseRepository)
+	shoppingListService := service.NewShoppingListService(shoppingListRepository, listItemRepository, eventBus)
+	expenseService := service.NewExpenseService(expenseRepository, eventBus)
 	inviteService := service.NewInviteService(invitationRepository, spaceRepository, userRepository, emailService)
 
 	return &App{
 		Cfg:                 cfg,
 		DB:                  database,
+		EventBus:            eventBus,
 		UserService:         userService,
 		AuthService:         authService,
 		EmailService:        emailService,

internal/event/bus.go

@@ -0,0 +1,84 @@
+package event
+
+import (
+	"fmt"
+	"log/slog"
+	"sync"
+)
+
+type Event struct {
+	Type string      `json:"type"`
+	Data interface{} `json:"data"`
+}
+
+type Broker struct {
+	mu          sync.RWMutex
+	subscribers map[string][]chan Event // map[spaceID][]chan Event
+}
+
+func NewBroker() *Broker {
+	return &Broker{
+		subscribers: make(map[string][]chan Event),
+	}
+}
+
+func (b *Broker) Subscribe(spaceID string) chan Event {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	ch := make(chan Event, 10) // buffer slightly to prevent blocking
+	b.subscribers[spaceID] = append(b.subscribers[spaceID], ch)
+
+	slog.Info("new subscriber", "space_id", spaceID)
+	return ch
+}
+
+func (b *Broker) Unsubscribe(spaceID string, ch chan Event) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+
+	subs := b.subscribers[spaceID]
+	for i, sub := range subs {
+		if sub == ch {
+			// Remove from slice
+			b.subscribers[spaceID] = append(subs[:i], subs[i+1:]...)
+			close(ch)
+			slog.Info("subscriber removed", "space_id", spaceID)
+			break
+		}
+	}
+
+	if len(b.subscribers[spaceID]) == 0 {
+		delete(b.subscribers, spaceID)
+	}
+}
+
+func (b *Broker) Publish(spaceID string, eventType string, data interface{}) {
+	b.mu.RLock()
+	defer b.mu.RUnlock()
+
+	subs, ok := b.subscribers[spaceID]
+	if !ok {
+		return
+	}
+
+	event := Event{
+		Type: eventType,
+		Data: data,
+	}
+
+	slog.Info("publishing event", "space_id", spaceID, "type", eventType)
+
+	for _, ch := range subs {
+		select {
+		case ch <- event:
+		default:
+			slog.Warn("subscriber channel full, dropping event", "space_id", spaceID)
+		}
+	}
+}
+
+// String format for SSE data
+func (e Event) String() string {
+	return fmt.Sprintf("event: %s\ndata: %v\n\n", e.Type, e.Data)
+}

internal/handler/space.go

@@ -7,11 +7,14 @@ import (
 	"time"
 
 	"git.juancwu.dev/juancwu/budgit/internal/ctxkeys"
+	"git.juancwu.dev/juancwu/budgit/internal/event"
 	"git.juancwu.dev/juancwu/budgit/internal/model"
 	"git.juancwu.dev/juancwu/budgit/internal/service"
 	"git.juancwu.dev/juancwu/budgit/internal/ui"
+	"git.juancwu.dev/juancwu/budgit/internal/ui/components/expense"
 	"git.juancwu.dev/juancwu/budgit/internal/ui/components/shoppinglist"
 	"git.juancwu.dev/juancwu/budgit/internal/ui/components/tag"
+	"git.juancwu.dev/juancwu/budgit/internal/ui/components/toast"
 	"git.juancwu.dev/juancwu/budgit/internal/ui/pages"
 )
 
@@ -21,15 +24,54 @@ type SpaceHandler struct {
 	listService    *service.ShoppingListService
 	expenseService *service.ExpenseService
 	inviteService  *service.InviteService
+	eventBus       *event.Broker
 }
 
-func NewSpaceHandler(ss *service.SpaceService, ts *service.TagService, sls *service.ShoppingListService, es *service.ExpenseService, is *service.InviteService) *SpaceHandler {
+func NewSpaceHandler(ss *service.SpaceService, ts *service.TagService, sls *service.ShoppingListService, es *service.ExpenseService, is *service.InviteService, eb *event.Broker) *SpaceHandler {
 	return &SpaceHandler{
 		spaceService:   ss,
 		tagService:     ts,
 		listService:    sls,
 		expenseService: es,
 		inviteService:  is,
+		eventBus:       eb,
+	}
+}
+
+func (h *SpaceHandler) StreamEvents(w http.ResponseWriter, r *http.Request) {
+	spaceID := r.PathValue("spaceID")
+
+	// Set headers for SSE
+	w.Header().Set("Content-Type", "text/event-stream")
+	w.Header().Set("Cache-Control", "no-cache")
+	w.Header().Set("Connection", "keep-alive")
+	w.Header().Set("Access-Control-Allow-Origin", "*")
+
+	// Subscribe to events
+	eventChan := h.eventBus.Subscribe(spaceID)
+	defer h.eventBus.Unsubscribe(spaceID, eventChan)
+
+	// Listen for client disconnect
+	ctx := r.Context()
+
+	// Flush immediately to establish connection
+	if flusher, ok := w.(http.Flusher); ok {
+		flusher.Flush()
+	}
+
+	for {
+		select {
+		case event := <-eventChan:
+			// Write event to stream
+			if _, err := w.Write([]byte(event.String())); err != nil {
+				return
+			}
+			if flusher, ok := w.(http.Flusher); ok {
+				flusher.Flush()
+			}
+		case <-ctx.Done():
+			return
+		}
 	}
 }
 
@@ -378,8 +420,14 @@ func (h *SpaceHandler) CreateInvite(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// TODO: Return a nice UI response (toast or list update)
-	w.Write([]byte("Invitation sent!"))
+	ui.Render(w, r, toast.Toast(toast.Props{
+		Title:       "Invitation sent",
+		Description: "An email has been sent to " + email,
+		Variant:     toast.VariantSuccess,
+		Icon:        true,
+		Dismissible: true,
+		Duration:    5000,
+	}))
 }
 
 func (h *SpaceHandler) JoinSpace(w http.ResponseWriter, r *http.Request) {
@@ -409,3 +457,56 @@ func (h *SpaceHandler) JoinSpace(w http.ResponseWriter, r *http.Request) {
 	})
 	http.Redirect(w, r, "/auth?invite=true", http.StatusTemporaryRedirect)
 }
+
+func (h *SpaceHandler) GetBalanceCard(w http.ResponseWriter, r *http.Request) {
+	spaceID := r.PathValue("spaceID")
+
+	balance, err := h.expenseService.GetBalanceForSpace(spaceID)
+	if err != nil {
+		slog.Error("failed to get balance", "error", err, "space_id", spaceID)
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	ui.Render(w, r, expense.BalanceCard(spaceID, balance, false))
+}
+
+func (h *SpaceHandler) GetExpensesList(w http.ResponseWriter, r *http.Request) {
+	spaceID := r.PathValue("spaceID")
+
+	expenses, err := h.expenseService.GetExpensesForSpace(spaceID)
+	if err != nil {
+		slog.Error("failed to get expenses", "error", err, "space_id", spaceID)
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	ui.Render(w, r, pages.ExpensesListContent(expenses))
+}
+
+func (h *SpaceHandler) GetShoppingListItems(w http.ResponseWriter, r *http.Request) {
+	spaceID := r.PathValue("spaceID")
+	listID := r.PathValue("listID")
+
+	items, err := h.listService.GetItemsForList(listID)
+	if err != nil {
+		slog.Error("failed to get items", "error", err, "list_id", listID)
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	ui.Render(w, r, pages.ShoppingListItems(spaceID, items))
+}
+
+func (h *SpaceHandler) GetLists(w http.ResponseWriter, r *http.Request) {
+	spaceID := r.PathValue("spaceID")
+
+	lists, err := h.listService.GetListsForSpace(spaceID)
+	if err != nil {
+		slog.Error("failed to get lists", "error", err, "space_id", spaceID)
+		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
+		return
+	}
+
+	ui.Render(w, r, pages.ListsContainer(lists))
+}

internal/routes/routes.go

@@ -14,7 +14,7 @@ func SetupRoutes(a *app.App) http.Handler {
 	auth := handler.NewAuthHandler(a.AuthService, a.InviteService)
 	home := handler.NewHomeHandler()
 	dashboard := handler.NewDashboardHandler()
-	space := handler.NewSpaceHandler(a.SpaceService, a.TagService, a.ShoppingListService, a.ExpenseService, a.InviteService)
+	space := handler.NewSpaceHandler(a.SpaceService, a.TagService, a.ShoppingListService, a.ExpenseService, a.InviteService, a.EventBus)
 
 	mux := http.NewServeMux()
 
@@ -57,6 +57,11 @@ func SetupRoutes(a *app.App) http.Handler {
 	spaceDashboardWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(spaceDashboardHandler)
 	mux.Handle("GET /app/spaces/{spaceID}", spaceDashboardWithAccess)
 
+	// SSE
+	streamHandler := middleware.RequireAuth(space.StreamEvents)
+	streamWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(streamHandler)
+	mux.Handle("GET /app/spaces/{spaceID}/stream", streamWithAccess)
+
 	listsPageHandler := middleware.RequireAuth(space.ListsPage)
 	listsPageWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(listsPageHandler)
 	mux.Handle("GET /app/spaces/{spaceID}/lists", listsPageWithAccess)
@@ -103,6 +108,23 @@ func SetupRoutes(a *app.App) http.Handler {
 	createExpenseWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(createExpenseHandler)
 	mux.Handle("POST /app/spaces/{spaceID}/expenses", createExpenseWithAccess)
 
+	// Component routes (HTMX updates)
+	balanceCardHandler := middleware.RequireAuth(space.GetBalanceCard)
+	balanceCardWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(balanceCardHandler)
+	mux.Handle("GET /app/spaces/{spaceID}/components/balance", balanceCardWithAccess)
+
+	expensesListHandler := middleware.RequireAuth(space.GetExpensesList)
+	expensesListWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(expensesListHandler)
+	mux.Handle("GET /app/spaces/{spaceID}/components/expenses", expensesListWithAccess)
+
+	shoppingListItemsHandler := middleware.RequireAuth(space.GetShoppingListItems)
+	shoppingListItemsWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(shoppingListItemsHandler)
+	mux.Handle("GET /app/spaces/{spaceID}/lists/{listID}/items", shoppingListItemsWithAccess)
+
+	listsComponentHandler := middleware.RequireAuth(space.GetLists)
+	listsComponentWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(listsComponentHandler)
+	mux.Handle("GET /app/spaces/{spaceID}/components/lists", listsComponentWithAccess)
+
 	// Invite routes
 	createInviteHandler := middleware.RequireAuth(space.CreateInvite)
 	createInviteWithAccess := middleware.RequireSpaceAccess(a.SpaceService)(createInviteHandler)

internal/service/expense.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"time"
 
+	"git.juancwu.dev/juancwu/budgit/internal/event"
 	"git.juancwu.dev/juancwu/budgit/internal/model"
 	"git.juancwu.dev/juancwu/budgit/internal/repository"
 	"github.com/google/uuid"
@@ -22,10 +23,14 @@ type CreateExpenseDTO struct {
 
 type ExpenseService struct {
 	expenseRepo repository.ExpenseRepository
+	eventBus    *event.Broker
 }
 
-func NewExpenseService(expenseRepo repository.ExpenseRepository) *ExpenseService {
-	return &ExpenseService{expenseRepo: expenseRepo}
+func NewExpenseService(expenseRepo repository.ExpenseRepository, eventBus *event.Broker) *ExpenseService {
+	return &ExpenseService{
+		expenseRepo: expenseRepo,
+		eventBus:    eventBus,
+	}
 }
 
 func (s *ExpenseService) CreateExpense(dto CreateExpenseDTO) (*model.Expense, error) {
@@ -54,6 +59,14 @@ func (s *ExpenseService) CreateExpense(dto CreateExpenseDTO) (*model.Expense, er
 		return nil, err
 	}
 
+	// Calculate new balance to broadcast
+	balance, _ := s.GetBalanceForSpace(dto.SpaceID)
+
+	s.eventBus.Publish(dto.SpaceID, "balance_changed", map[string]interface{}{
+		"balance": balance,
+	})
+	s.eventBus.Publish(dto.SpaceID, "expenses_updated", nil)
+
 	return expense, nil
 }
 

internal/service/shopping_list.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 	"time"
 
+	"git.juancwu.dev/juancwu/budgit/internal/event"
 	"git.juancwu.dev/juancwu/budgit/internal/model"
 	"git.juancwu.dev/juancwu/budgit/internal/repository"
 	"github.com/google/uuid"
@@ -13,12 +14,14 @@ import (
 type ShoppingListService struct {
 	listRepo repository.ShoppingListRepository
 	itemRepo repository.ListItemRepository
+	eventBus *event.Broker
 }
 
-func NewShoppingListService(listRepo repository.ShoppingListRepository, itemRepo repository.ListItemRepository) *ShoppingListService {
+func NewShoppingListService(listRepo repository.ShoppingListRepository, itemRepo repository.ListItemRepository, eventBus *event.Broker) *ShoppingListService {
 	return &ShoppingListService{
 		listRepo: listRepo,
 		itemRepo: itemRepo,
+		eventBus: eventBus,
 	}
 }
 
@@ -43,6 +46,8 @@ func (s *ShoppingListService) CreateList(spaceID, name string) (*model.ShoppingL
 		return nil, err
 	}
 
+	s.eventBus.Publish(spaceID, "list_created", nil)
+
 	return list, nil
 }
 
@@ -76,13 +81,23 @@ func (s *ShoppingListService) UpdateList(listID, name string) (*model.ShoppingLi
 }
 
 func (s *ShoppingListService) DeleteList(listID string) error {
+	// Need spaceID to publish event
+	list, err := s.listRepo.GetByID(listID)
+	if err != nil {
+		return err
+	}
+
 	// First delete all items in the list
-	err := s.itemRepo.DeleteByListID(listID)
+	err = s.itemRepo.DeleteByListID(listID)
 	if err != nil {
 		return fmt.Errorf("failed to delete items in list: %w", err)
 	}
 	// Then delete the list itself
-	return s.listRepo.Delete(listID)
+	err = s.listRepo.Delete(listID)
+	if err == nil {
+		s.eventBus.Publish(list.SpaceID, "list_deleted", nil)
+	}
+	return err
 }
 
 // Item methods
@@ -108,6 +123,12 @@ func (s *ShoppingListService) AddItemToList(listID, name, createdBy string) (*mo
 		return nil, err
 	}
 
+	// Get Space ID
+	list, err := s.listRepo.GetByID(listID)
+	if err == nil {
+		s.eventBus.Publish(list.SpaceID, "item_added", nil)
+	}
+
 	return item, nil
 }
 
@@ -138,9 +159,27 @@ func (s *ShoppingListService) UpdateItem(itemID, name string, isChecked bool) (*
 		return nil, err
 	}
 
+	// Get Space ID via List
+	list, err := s.listRepo.GetByID(item.ListID)
+	if err == nil {
+		s.eventBus.Publish(list.SpaceID, "item_updated", nil)
+	}
+
 	return item, nil
 }
 
 func (s *ShoppingListService) DeleteItem(itemID string) error {
-	return s.itemRepo.Delete(itemID)
+	item, err := s.itemRepo.GetByID(itemID)
+	if err != nil {
+		return err
+	}
+
+	err = s.itemRepo.Delete(itemID)
+	if err == nil {
+		list, err := s.listRepo.GetByID(item.ListID)
+		if err == nil {
+			s.eventBus.Publish(list.SpaceID, "item_deleted", nil)
+		}
+	}
+	return err
 }

internal/ui/components/expense/expense.templ

@@ -84,8 +84,15 @@ templ AddExpenseForm(space *model.Space, tags []*model.Tag, lists []*model.Shopp
 	</form>
 }
 
-templ BalanceCard(balance int, oob bool) {
-	<div id="balance-card" class="border rounded-lg p-4 bg-card text-card-foreground" hx-swap-oob?={ oob }>
+templ BalanceCard(spaceID string, balance int, oob bool) {
+	<div
+		id="balance-card"
+		class="border rounded-lg p-4 bg-card text-card-foreground"
+		hx-swap-oob?={ oob }
+		hx-get={ "/app/spaces/" + spaceID + "/components/balance" }
+		hx-trigger="sse:balance_changed"
+		hx-swap="outerHTML"
+	>
 		<h2 class="text-lg font-semibold">Current Balance</h2>
 		<p class={ "text-3xl font-bold", templ.KV("text-destructive", balance < 0) }>
 			{ fmt.Sprintf("$%.2f", float64(balance)/100.0) }

internal/ui/layouts/space.templ

@@ -93,6 +93,7 @@ templ Space(title string, space *model.Space) {
 				}
 			}
 			@sidebar.Inset() {
+				<div hx-sse={ "connect:/app/spaces/" + space.ID + "/stream" } class="flex flex-col h-full">
 					// Top Navigation Bar
 					<header class="sticky top-0 z-10 border-b bg-background">
 						<div class="flex h-14 items-center px-6">
@@ -129,6 +130,7 @@ templ Space(title string, space *model.Space) {
 					<main class="flex-1 p-6">
 						{ children... }
 					</main>
+				</div>
 			}
 		}
 	}

internal/ui/pages/app_space_expenses.templ

@@ -33,10 +33,23 @@ templ SpaceExpensesPage(space *model.Space, expenses []*model.Expense, balance i
 			</div>
 
 			// Balance Card
-			@expense.BalanceCard(balance, false)
+			@expense.BalanceCard(space.ID, balance, false)
 
 			// List of expenses
-			<div id="expenses-list" class="border rounded-lg">
+			<div
+				id="expenses-list"
+				class="border rounded-lg"
+				hx-get={ "/app/spaces/" + space.ID + "/components/expenses" }
+				hx-trigger="sse:expenses_updated"
+				hx-swap="innerHTML"
+			>
+				@ExpensesListContent(expenses)
+			</div>
+		</div>
+	}
+}
+
+templ ExpensesListContent(expenses []*model.Expense) {
 	<h2 class="text-lg font-semibold p-4">History</h2>
 	<div class="divide-y">
 		if len(expenses) == 0 {
@@ -46,9 +59,6 @@ templ SpaceExpensesPage(space *model.Space, expenses []*model.Expense, balance i
 			@ExpenseListItem(expense)
 		}
 	</div>
-			</div>
-		</div>
-	}
 }
 
 templ ExpenseListItem(expense *model.Expense) {
@@ -73,5 +83,5 @@ templ ExpenseListItem(expense *model.Expense) {
 
 templ ExpenseCreatedResponse(newExpense *model.Expense, balance int) {
 	@ExpenseListItem(newExpense)
-	@expense.BalanceCard(balance, true)
+	@expense.BalanceCard(newExpense.SpaceID, balance, true)
 }

internal/ui/pages/app_space_list_detail.templ

@@ -31,15 +31,25 @@ templ SpaceListDetailPage(space *model.Space, list *model.ShoppingList, items []
 					Add Item
 				}
 			</form>
-			<div id="items-container" class="border rounded-lg">
+			<div
+				id="items-container"
+				class="border rounded-lg"
+				hx-get={ "/app/spaces/" + space.ID + "/lists/" + list.ID + "/items" }
+				hx-trigger="sse:item_added, sse:item_updated, sse:item_deleted"
+				hx-swap="innerHTML"
+			>
+				@ShoppingListItems(space.ID, items)
+			</div>
+		</div>
+	}
+}
+
+templ ShoppingListItems(spaceID string, items []*model.ListItem) {
 	if len(items) == 0 {
 		<p class="text-center text-muted-foreground p-8">This list is empty.</p>
 	} else {
 		for _, item := range items {
-						@shoppinglist.ItemDetail(space.ID, item)
+			@shoppinglist.ItemDetail(spaceID, item)
 		}
 	}
-			</div>
-		</div>
-	}
 }

internal/ui/pages/app_space_lists.templ

@@ -33,11 +33,21 @@ templ SpaceListsPage(space *model.Space, lists []*model.ShoppingList) {
 					Create
 				}
 			</form>
-			<div id="lists-container" class="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-4">
+			<div
+				id="lists-container"
+				class="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-4"
+				hx-get={ "/app/spaces/" + space.ID + "/components/lists" }
+				hx-trigger="sse:list_created, sse:list_deleted"
+				hx-swap="innerHTML"
+			>
+				@ListsContainer(lists)
+			</div>
+		</div>
+	}
+}
+
+templ ListsContainer(lists []*model.ShoppingList) {
 	for _, list := range lists {
 		@shoppinglist.ListItem(list)
 	}
-			</div>
-		</div>
-	}
 }