Files
iu 2b2b342492 feat: implement shared-album multi-user photo album
Backend (Go/Gin/pgx): env config, pgx pool with retries, Garage S3 client
(path-style, region garage), embedded golang-migrate migrations, JWT auth with
refresh rotation, albums CRUD, members/roles/invites with no-escalation matrix,
photo upload + async imaging/goexif WebP variants, cursor pagination, presigned
URLs, likes/comments, SSE hub (album + personal), notifications, share links.

Frontend (SvelteKit 2 + Svelte 5 + Tailwind v4): API wrapper with 401 refresh,
auth store, all screens, Uploader/PhotoGrid/Lightbox/Comments, SSE client with
reconnect + REST catch-up, three themes + system via data-theme.

Deploy without Docker: Makefile builds the frontend into backend/static and
embeds it (go:embed) into a single statically linked binary; systemd unit and
nginx SSE example included.

Use gen2brain/webp (-tags nodynamic) instead of cgo kolesa-team/go-webp to keep
CGO_ENABLED=0 static builds; design.md/proposal.md updated accordingly.
2026-10-10 12:50:33 +03:00

140 lines
2.7 KiB
Go

package sse
import (
"sync"
)
type Event struct {
Type string
Data any
}
type subscriber struct {
ch chan Event
closed bool
}
type Subscription struct {
hub *Hub
key string
personal bool
sub *subscriber
once sync.Once
}
func (s *Subscription) Events() <-chan Event { return s.sub.ch }
func (s *Subscription) Close() {
s.once.Do(func() {
if s.personal {
s.hub.unsubscribeUser(s.key, s.sub)
} else {
s.hub.unsubscribeAlbum(s.key, s.sub)
}
})
}
type Hub struct {
mu sync.RWMutex
albums map[string]map[*subscriber]struct{}
users map[string]map[*subscriber]struct{}
buffer int
}
func NewHub(buffer int) *Hub {
if buffer <= 0 {
buffer = 64
}
return &Hub{
albums: make(map[string]map[*subscriber]struct{}),
users: make(map[string]map[*subscriber]struct{}),
buffer: buffer,
}
}
func (h *Hub) SubscribeAlbum(albumID string) *Subscription {
sub := &subscriber{ch: make(chan Event, h.buffer)}
h.mu.Lock()
if h.albums[albumID] == nil {
h.albums[albumID] = make(map[*subscriber]struct{})
}
h.albums[albumID][sub] = struct{}{}
h.mu.Unlock()
return &Subscription{hub: h, key: albumID, sub: sub}
}
func (h *Hub) SubscribeUser(userID string) *Subscription {
sub := &subscriber{ch: make(chan Event, h.buffer)}
h.mu.Lock()
if h.users[userID] == nil {
h.users[userID] = make(map[*subscriber]struct{})
}
h.users[userID][sub] = struct{}{}
h.mu.Unlock()
return &Subscription{hub: h, key: userID, personal: true, sub: sub}
}
func (h *Hub) Publish(albumID, eventType string, data any) {
if albumID == "" {
return
}
h.mu.RLock()
defer h.mu.RUnlock()
h.broadcast(h.albums[albumID], Event{Type: eventType, Data: data})
}
func (h *Hub) PublishUser(userID, eventType string, data any) {
if userID == "" {
return
}
h.mu.RLock()
defer h.mu.RUnlock()
h.broadcast(h.users[userID], Event{Type: eventType, Data: data})
}
func (h *Hub) broadcast(subs map[*subscriber]struct{}, ev Event) {
for sub := range subs {
if sub.closed {
continue
}
select {
case sub.ch <- ev:
default:
// slow client: drop it (backpressure)
sub.closed = true
close(sub.ch)
}
}
}
func (h *Hub) unsubscribeAlbum(albumID string, sub *subscriber) {
h.mu.Lock()
defer h.mu.Unlock()
if subs, ok := h.albums[albumID]; ok {
delete(subs, sub)
if len(subs) == 0 {
delete(h.albums, albumID)
}
}
closeIfOpen(sub)
}
func (h *Hub) unsubscribeUser(userID string, sub *subscriber) {
h.mu.Lock()
defer h.mu.Unlock()
if subs, ok := h.users[userID]; ok {
delete(subs, sub)
if len(subs) == 0 {
delete(h.users, userID)
}
}
closeIfOpen(sub)
}
func closeIfOpen(sub *subscriber) {
if !sub.closed {
sub.closed = true
close(sub.ch)
}
}