Add accounts and multi-tenancy

Every event, profile and photo is now scoped to a signed-in account, so separate people can track separate puppies on one server. Server: - users + sessions tables; bcrypt passwords; random session tokens stored hashed and set as an HttpOnly cookie. Middleware gates /api/* behind a valid session. - register/login/logout/me endpoints. Registration requires a shared invite code (-invite-code / PUPPY_INVITE_CODE); empty disables it. - events, config and photos are keyed by user_id; the sync upsert guards against cross-user overwrites and reads are scoped, so accounts are isolated. Photos live under photos/<user_id>/ and are only served to their owner. - in-place schema migration adds user_id and reshapes config; legacy single-tenant data (including imported events.json) is parked ownerless and adopted by the first account to register. Client: - login/register gate in front of the app; the tracker only boots once the session check resolves. localStorage is namespaced per user. - 401s bounce back to login; an offline reload falls back to the last cached session so offline-first still works. Logout clears the session and reloads. Deployment: - module.nix gains inviteCodeFile (secret via EnvironmentFile) and secureCookies options. Verified end to end (curl + a headless-browser run of the auth flow): isolation between accounts, invite enforcement, first-user adoption, photo ownership, and session persistence across reload. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-07-09 18:20:36 +00:00
parent d95cd52086
commit 706d8d8d9f
11 changed files with 896 additions and 90 deletions
@@ -54,12 +54,12 @@ func newConfigStore(db *sql.DB) *ConfigStore {
 	return &ConfigStore{db: db}
 }

-func (cs *ConfigStore) get() Config {
+func (cs *ConfigStore) get(userID string) Config {
 	var c Config
-	// The profile lives in a single row (id = 1). A missing row is the
-	// pre-configuration state, so a zero-value Config is the right answer.
+	// One profile row per user. A missing row is the pre-configuration state,
+	// so a zero-value Config is the right answer.
 	err := cs.db.QueryRow(
-		`SELECT name, birthday, updated FROM config WHERE id = 1`,
+		`SELECT name, birthday, updated FROM config WHERE user_id = ?`, userID,
 	).Scan(&c.Name, &c.Birthday, &c.UpdatedAt)
 	if err != nil && !errors.Is(err, sql.ErrNoRows) {
 		log.Printf("config get: %v", err)
@@ -67,22 +67,22 @@ func (cs *ConfigStore) get() Config {
 	return c
 }

-// merge applies an incoming config with last-write-wins by UpdatedAt and
-// returns the resulting stored config (which the caller sends back).
-func (cs *ConfigStore) merge(in Config) (Config, error) {
+// merge applies an incoming config for one user with last-write-wins by
+// UpdatedAt and returns the resulting stored config (which the caller sends back).
+func (cs *ConfigStore) merge(userID string, in Config) (Config, error) {
 	// The upsert's WHERE clause enforces last-write-wins: the incoming row only
 	// replaces the stored one when it is strictly newer.
 	_, err := cs.db.Exec(`
-		INSERT INTO config (id, name, birthday, updated)
-		VALUES (1, ?, ?, ?)
-		ON CONFLICT(id) DO UPDATE SET
+		INSERT INTO config (user_id, name, birthday, updated)
+		VALUES (?, ?, ?, ?)
+		ON CONFLICT(user_id) DO UPDATE SET
 			name = excluded.name, birthday = excluded.birthday, updated = excluded.updated
 		WHERE excluded.updated > config.updated`,
-		in.Name, in.Birthday, in.UpdatedAt)
+		userID, in.Name, in.Birthday, in.UpdatedAt)
 	if err != nil {
 		return Config{}, err
 	}
-	return cs.get(), nil
+	return cs.get(userID), nil
 }

 type Store struct {
@@ -93,9 +93,10 @@ func newStore(db *sql.DB) *Store {
 	return &Store{db: db}
 }

-// sync merges client events into the store using last-write-wins by UpdatedAt,
-// then returns the full merged set (including tombstones, which must propagate).
-func (s *Store) sync(client []Event) ([]Event, error) {
+// sync merges one user's client events into the store using last-write-wins by
+// UpdatedAt, then returns that user's full merged set (tombstones included, as
+// they must propagate).
+func (s *Store) sync(userID string, client []Event) ([]Event, error) {
 	tx, err := s.db.Begin()
 	if err != nil {
 		return nil, err
@@ -104,14 +105,18 @@ func (s *Store) sync(client []Event) ([]Event, error) {

 	// The WHERE clause on the upsert is the last-write-wins rule: an incoming
 	// event only overwrites the stored one when its updatedAt is strictly newer.
+	// The `events.user_id = excluded.user_id` guard means one user can never
+	// clobber another's row even if a client forges a colliding event ID —
+	// the row stays put and, because reads are scoped, stays invisible to them.
 	stmt, err := tx.Prepare(`
-		INSERT INTO events (id, type, at, note, photo_id, weight, updated, deleted)
-		VALUES (?, ?, ?, ?, ?, ?, ?, ?)
+		INSERT INTO events (id, type, at, note, photo_id, weight, updated, deleted, user_id)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
 		ON CONFLICT(id) DO UPDATE SET
 			type = excluded.type, at = excluded.at, note = excluded.note,
 			photo_id = excluded.photo_id, weight = excluded.weight,
 			updated = excluded.updated, deleted = excluded.deleted
-		WHERE excluded.updated > events.updated`)
+		WHERE excluded.updated > events.updated
+		  AND events.user_id = excluded.user_id`)
 	if err != nil {
 		return nil, err
 	}
@@ -122,7 +127,7 @@ func (s *Store) sync(client []Event) ([]Event, error) {
 			continue
 		}
 		if _, err := stmt.Exec(
-			ce.ID, ce.Type, ce.At, ce.Note, ce.PhotoID, ce.Weight, ce.UpdatedAt, ce.Deleted,
+			ce.ID, ce.Type, ce.At, ce.Note, ce.PhotoID, ce.Weight, ce.UpdatedAt, ce.Deleted, userID,
 		); err != nil {
 			return nil, err
 		}
@@ -130,13 +135,14 @@ func (s *Store) sync(client []Event) ([]Event, error) {
 	if err := tx.Commit(); err != nil {
 		return nil, err
 	}
-	return s.all()
+	return s.all(userID)
 }

-// all returns every stored event, tombstones included.
-func (s *Store) all() ([]Event, error) {
+// all returns one user's events, tombstones included.
+func (s *Store) all(userID string) ([]Event, error) {
 	rows, err := s.db.Query(
-		`SELECT id, type, at, note, photo_id, weight, updated, deleted FROM events`)
+		`SELECT id, type, at, note, photo_id, weight, updated, deleted
+		   FROM events WHERE user_id = ?`, userID)
 	if err != nil {
 		return nil, err
 	}
@@ -175,6 +181,9 @@ func openDB(path string) (*sql.DB, error) {
 			return nil, err
 		}
 	}
+	// Fresh-install schema. Every row is scoped to a user_id; the empty string
+	// is the "ownerless" bucket that legacy single-tenant data lands in until
+	// the first account adopts it (see Auth.adopt).
 	schema := `
 		CREATE TABLE IF NOT EXISTS events (
 			id       TEXT PRIMARY KEY,
@@ -184,21 +193,105 @@ func openDB(path string) (*sql.DB, error) {
 			photo_id TEXT NOT NULL DEFAULT '',
 			weight   REAL NOT NULL DEFAULT 0,
 			updated  INTEGER NOT NULL DEFAULT 0,
-			deleted  INTEGER NOT NULL DEFAULT 0
+			deleted  INTEGER NOT NULL DEFAULT 0,
+			user_id  TEXT NOT NULL DEFAULT ''
 		);
+		CREATE INDEX IF NOT EXISTS idx_events_user ON events(user_id);
 		CREATE TABLE IF NOT EXISTS config (
-			id       INTEGER PRIMARY KEY CHECK (id = 1),
+			user_id  TEXT PRIMARY KEY,
 			name     TEXT NOT NULL DEFAULT '',
 			birthday TEXT NOT NULL DEFAULT '',
 			updated  INTEGER NOT NULL DEFAULT 0
+		);
+		CREATE TABLE IF NOT EXISTS users (
+			id       TEXT PRIMARY KEY,
+			email    TEXT NOT NULL UNIQUE COLLATE NOCASE,
+			password TEXT NOT NULL,
+			created  INTEGER NOT NULL
+		);
+		CREATE TABLE IF NOT EXISTS sessions (
+			token   TEXT PRIMARY KEY,
+			user_id TEXT NOT NULL,
+			created INTEGER NOT NULL,
+			expires INTEGER NOT NULL
 		);`
 	if _, err := db.Exec(schema); err != nil {
 		db.Close()
 		return nil, err
 	}
+	if err := migrateSchema(db); err != nil {
+		db.Close()
+		return nil, err
+	}
 	return db, nil
 }

+// migrateSchema upgrades a single-tenant database (from before accounts existed)
+// in place: it adds events.user_id and rewrites the config table from its
+// old single-row (id = 1) shape to one keyed by user_id. Pre-accounts data ends
+// up ownerless (user_id = ”), ready for the first account to adopt. It is a
+// no-op on a fresh DB, where openDB already created the current schema.
+func migrateSchema(db *sql.DB) error {
+	has, err := columnExists(db, "events", "user_id")
+	if err != nil {
+		return err
+	}
+	if !has {
+		if _, err := db.Exec(`ALTER TABLE events ADD COLUMN user_id TEXT NOT NULL DEFAULT ''`); err != nil {
+			return err
+		}
+		if _, err := db.Exec(`CREATE INDEX IF NOT EXISTS idx_events_user ON events(user_id)`); err != nil {
+			return err
+		}
+	}
+	oldConfig, err := columnExists(db, "config", "id")
+	if err != nil {
+		return err
+	}
+	if oldConfig {
+		// Rebuild config keyed by user_id, moving the lone id=1 row into the
+		// ownerless bucket.
+		stmts := []string{
+			`ALTER TABLE config RENAME TO config_old`,
+			`CREATE TABLE config (
+				user_id  TEXT PRIMARY KEY,
+				name     TEXT NOT NULL DEFAULT '',
+				birthday TEXT NOT NULL DEFAULT '',
+				updated  INTEGER NOT NULL DEFAULT 0
+			)`,
+			`INSERT INTO config (user_id, name, birthday, updated)
+				SELECT '', name, birthday, updated FROM config_old WHERE id = 1`,
+			`DROP TABLE config_old`,
+		}
+		for _, s := range stmts {
+			if _, err := db.Exec(s); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// columnExists reports whether the given table has a column of the given name.
+// A missing table reports false (no error), which is what fresh installs want.
+func columnExists(db *sql.DB, table, col string) (bool, error) {
+	rows, err := db.Query(`SELECT name FROM pragma_table_info(?)`, table)
+	if err != nil {
+		return false, err
+	}
+	defer rows.Close()
+	for rows.Next() {
+		var name string
+		if err := rows.Scan(&name); err != nil {
+			return false, err
+		}
+		if name == col {
+			return true, nil
+		}
+	}
+	return false, rows.Err()
+}
+
 // migrateJSON imports a pre-SQLite events.json / config.json sitting in dataDir
 // into an otherwise-empty database, then renames each file to *.imported so the
 // import runs exactly once. It is a no-op when the DB already holds data or the
@@ -232,8 +325,10 @@ func importEvents(db *sql.DB, path string) error {
 	if err != nil && !errors.Is(err, io.EOF) {
 		return err
 	}
+	// Imported as ownerless (user_id = ""); the first account to register adopts
+	// them. Mirrors how in-place schema migration parks legacy rows.
 	store := newStore(db)
-	if _, err := store.sync(evs); err != nil {
+	if _, err := store.sync("", evs); err != nil {
 		return err
 	}
 	log.Printf("migrated %d events from %s", len(evs), path)
@@ -266,7 +361,8 @@ func importConfig(db *sql.DB, path string) error {
 		// Nothing meaningful to import; leave config empty.
 		return os.Rename(path, path+".imported")
 	}
-	if _, err := newConfigStore(db).merge(c); err != nil {
+	// Ownerless until the first account adopts it (see importEvents).
+	if _, err := newConfigStore(db).merge("", c); err != nil {
 		return err
 	}
 	log.Printf("migrated config from %s", path)
@@ -292,6 +388,10 @@ func main() {
 	addr := flag.String("addr", ":8080", "listen address (e.g. :8080 or 0.0.0.0:8080)")
 	dataPath := flag.String("data", "puppy.db", "path to SQLite database file")
 	staticDir := flag.String("static", "", "directory of static files to serve")
+	inviteCode := flag.String("invite-code", os.Getenv("PUPPY_INVITE_CODE"),
+		"shared secret required to register (env PUPPY_INVITE_CODE); empty disables registration")
+	secureCookies := flag.Bool("secure-cookies", false,
+		"mark session cookies Secure (enable when served over HTTPS / behind a TLS proxy)")
 	flag.Parse()

 	db, err := openDB(*dataPath)
@@ -313,9 +413,19 @@ func main() {
 		log.Fatalf("mkdir photos: %v", err)
 	}

+	auth := newAuth(db, *inviteCode, *secureCookies, photosDir)
+	if *inviteCode == "" {
+		log.Print("WARNING: no invite code set — registration is disabled (set -invite-code / PUPPY_INVITE_CODE)")
+	}
+
 	mux := http.NewServeMux()

-	mux.HandleFunc("/api/events/sync", func(w http.ResponseWriter, r *http.Request) {
+	mux.HandleFunc("/api/register", auth.handleRegister)
+	mux.HandleFunc("/api/login", auth.handleLogin)
+	mux.HandleFunc("/api/logout", auth.handleLogout)
+	mux.HandleFunc("/api/me", auth.requireUser(auth.handleMe))
+
+	mux.HandleFunc("/api/events/sync", auth.requireUser(func(w http.ResponseWriter, r *http.Request) {
 		if r.Method != http.MethodPost {
 			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
 			return
@@ -325,7 +435,7 @@ func main() {
 			http.Error(w, "bad json: "+err.Error(), http.StatusBadRequest)
 			return
 		}
-		merged, err := store.sync(req.Events)
+		merged, err := store.sync(userID(r), req.Events)
 		if err != nil {
 			log.Printf("sync: %v", err)
 			http.Error(w, "server error", http.StatusInternalServerError)
@@ -337,11 +447,11 @@ func main() {
 			Events:    merged,
 			ServerNow: time.Now().UnixMilli(),
 		})
-	})
+	}))

-	// GET  /api/config — return the shared puppy profile.
+	// GET  /api/config — return the caller's puppy profile.
 	// PUT  /api/config — update it (last-write-wins by updatedAt).
-	mux.HandleFunc("/api/config", func(w http.ResponseWriter, r *http.Request) {
+	mux.HandleFunc("/api/config", auth.requireUser(func(w http.ResponseWriter, r *http.Request) {
 		writeConfig := func(c Config) {
 			w.Header().Set("Content-Type", "application/json")
 			w.Header().Set("Cache-Control", "no-store")
@@ -349,7 +459,7 @@ func main() {
 		}
 		switch r.Method {
 		case http.MethodGet:
-			writeConfig(configStore.get())
+			writeConfig(configStore.get(userID(r)))
 		case http.MethodPut, http.MethodPost:
 			var in Config
 			if err := json.NewDecoder(io.LimitReader(r.Body, 1<<16)).Decode(&in); err != nil {
@@ -364,7 +474,7 @@ func main() {
 				http.Error(w, "invalid birthday (want YYYY-MM-DD)", http.StatusBadRequest)
 				return
 			}
-			merged, err := configStore.merge(in)
+			merged, err := configStore.merge(userID(r), in)
 			if err != nil {
 				log.Printf("config save: %v", err)
 				http.Error(w, "server error", http.StatusInternalServerError)
@@ -374,7 +484,7 @@ func main() {
 		default:
 			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
 		}
-	})
+	}))

 	mux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
 		w.Write([]byte("ok"))
@@ -383,7 +493,7 @@ func main() {
 	// POST /api/photos — multipart upload with form fields `id` (UUID) and
 	// `file` (JPEG). The client generates the ID so the event referencing
 	// the photo can be written before the upload round-trips.
-	mux.HandleFunc("/api/photos", func(w http.ResponseWriter, r *http.Request) {
+	mux.HandleFunc("/api/photos", auth.requireUser(func(w http.ResponseWriter, r *http.Request) {
 		if r.Method != http.MethodPost {
 			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
 			return
@@ -405,7 +515,14 @@ func main() {
 		}
 		defer file.Close()

-		dstPath := filepath.Join(photosDir, id+".jpg")
+		// Photos live under the owner's directory so a photo can only ever be
+		// read back by the account that uploaded it.
+		userDir := filepath.Join(photosDir, userID(r))
+		if err := os.MkdirAll(userDir, 0o755); err != nil {
+			http.Error(w, "mkdir: "+err.Error(), http.StatusInternalServerError)
+			return
+		}
+		dstPath := filepath.Join(userDir, id+".jpg")
 		tmp := dstPath + ".tmp"
 		dst, err := os.Create(tmp)
 		if err != nil {
@@ -432,11 +549,12 @@ func main() {
 		w.Header().Set("Content-Type", "application/json")
 		w.Header().Set("Cache-Control", "no-store")
 		_ = json.NewEncoder(w).Encode(map[string]string{"id": id})
-	})
+	}))

-	// GET /api/photos/<id> — serves the JPEG. Photos are immutable per ID
-	// so we mark them as long-lived; both browser and SW can cache freely.
-	mux.HandleFunc("/api/photos/", func(w http.ResponseWriter, r *http.Request) {
+	// GET /api/photos/<id> — serves the caller's own JPEG. Photos are immutable
+	// per ID so we mark them as long-lived; the private cache keeps them per
+	// user. Serving only from the caller's directory makes ownership implicit.
+	mux.HandleFunc("/api/photos/", auth.requireUser(func(w http.ResponseWriter, r *http.Request) {
 		if r.Method != http.MethodGet && r.Method != http.MethodHead {
 			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
 			return
@@ -446,7 +564,7 @@ func main() {
 			http.Error(w, "invalid id", http.StatusBadRequest)
 			return
 		}
-		path := filepath.Join(photosDir, id+".jpg")
+		path := filepath.Join(photosDir, userID(r), id+".jpg")
 		f, err := os.Open(path)
 		if err != nil {
 			http.NotFound(w, r)
@@ -459,9 +577,9 @@ func main() {
 			return
 		}
 		w.Header().Set("Content-Type", "image/jpeg")
-		w.Header().Set("Cache-Control", "public, max-age=31536000, immutable")
+		w.Header().Set("Cache-Control", "private, max-age=31536000, immutable")
 		http.ServeContent(w, r, path, stat.ModTime(), f)
-	})
+	}))

 	if *staticDir != "" {
 		fileServer := http.FileServer(http.Dir(*staticDir))