Notes/src/routes/error_handlers.ts

import type { Application, NextFunction, Request, Response } from "express";
import log from "../services/log.js";
import NotFoundError from "../errors/not_found_error.js";
import ForbiddenError from "../errors/forbidden_error.js";

function register(app: Application) {
    app.use((err: any, req: Request, res: Response, next: NextFunction) => {
        if (err.code !== "EBADCSRFTOKEN") {
            return next(err);
        }

        log.error(`Invalid CSRF token: ${req.headers["x-csrf-token"]}, secret: ${req.cookies["_csrf"]}`);
        next(new ForbiddenError("Invalid CSRF token"));
    });

    // catch 404 and forward to error handler
    app.use((req, res, next) => {
        const err = new NotFoundError(`Router not found for request ${req.method} ${req.url}`);
        next(err);
    });

    // error handler
    app.use((err: any, req: Request, res: Response, _next: NextFunction) => {
        if (err.status !== 404) {
            log.info(err);
        } else {
            log.info(`${err.status} ${req.method} ${req.url}`);
        }

        res.status(err.status || 500);
        res.send({
            message: err.message
        });
    });
}

export default {
    register
};