feat(backend): make snowflake IDs usable in /users/{id}, /users/{id}/members

backend/db/member.go

@@ -73,9 +73,22 @@ func (db *DB) Member(ctx context.Context, id xid.ID) (m Member, err error) {
 	return m, nil
 }
 
+func (db *DB) MemberBySnowflake(ctx context.Context, id common.MemberID) (m Member, err error) {
+	sql, args, err := sq.Select("*").From("members").Where("snowflake_id = ?", id).ToSql()
+	if err != nil {
+		return m, errors.Wrap(err, "building sql")
+	}
+
+	err = pgxscan.Get(ctx, db, &m, sql, args...)
+	if err != nil {
+		return m, errors.Wrap(err, "executing query")
+	}
+	return m, nil
+}
+
 // UserMember returns a member scoped by user.
 func (db *DB) UserMember(ctx context.Context, userID xid.ID, memberRef string) (m Member, err error) {
-	sql, args, err := sq.Select("*").From("members").Where("user_id = ?", userID).Where("(id = ? or name = ?)", memberRef, memberRef).ToSql()
+	sql, args, err := sq.Select("*").From("members").Where("user_id = ?", userID).Where("(id = ? or name = ? or snowflake_id = ?)", memberRef, memberRef, memberRef).ToSql()
 	if err != nil {
 		return m, errors.Wrap(err, "building sql")
 	}

backend/db/user.go

@@ -495,6 +495,26 @@ func (db *DB) User(ctx context.Context, id xid.ID) (u User, err error) {
 	return u, nil
 }
 
+// UserBySnowflake gets a user by their snowflake ID.
+func (db *DB) UserBySnowflake(ctx context.Context, id common.UserID) (u User, err error) {
+	sql, args, err := sq.Select("*", "(SELECT instance FROM fediverse_apps WHERE id = users.fediverse_app_id) AS fediverse_instance").
+		From("users").Where("snowflake_id = ?", id).ToSql()
+	if err != nil {
+		return u, errors.Wrap(err, "building sql")
+	}
+
+	err = pgxscan.Get(ctx, db, &u, sql, args...)
+	if err != nil {
+		if errors.Cause(err) == pgx.ErrNoRows {
+			return u, ErrUserNotFound
+		}
+
+		return u, errors.Wrap(err, "getting user from db")
+	}
+
+	return u, nil
+}
+
 // Username gets a user by username.
 func (db *DB) Username(ctx context.Context, name string) (u User, err error) {
 	sql, args, err := sq.Select("*").From("users").Where("username = ?", name).ToSql()

backend/routes/v1/member/get_member.go

@@ -191,12 +191,22 @@ func (s *Server) getMeMember(w http.ResponseWriter, r *http.Request) error {
 }
 
 func (s *Server) parseUser(ctx context.Context, userRef string) (u db.User, err error) {
-	if id, err := xid.FromString(userRef); err != nil {
+	// check xid first
+	if id, err := xid.FromString(userRef); err == nil {
 		u, err := s.DB.User(ctx, id)
 		if err == nil {
 			return u, nil
 		}
 	}
 
+	// if not an xid, check by snowflake
+	if id, err := common.ParseSnowflake(userRef); err == nil {
+		u, err := s.DB.UserBySnowflake(ctx, common.UserID(id))
+		if err == nil {
+			return u, nil
+		}
+	}
+
+	// else, use username
 	return s.DB.Username(ctx, userRef)
 }

backend/routes/v1/user/get_user.go

@@ -129,6 +129,15 @@ func (s *Server) getUser(w http.ResponseWriter, r *http.Request) (err error) {
 		}
 	}
 
+	if u.ID.IsNil() {
+		if id, err := common.ParseSnowflake(userRef); err == nil {
+			u, err = s.DB.UserBySnowflake(ctx, common.UserID(id))
+			if err != nil {
+				log.Errorf("getting user by snowflake: %v", err)
+			}
+		}
+	}
+
 	if u.ID.IsNil() {
 		u, err = s.DB.Username(ctx, userRef)
 		if err == db.ErrUserNotFound {