Catchalls not working in Express 5

[lexisother]

I'm not sure if I'm doing things wrong or misunderstanding the docs, but I'm running into some problems with Express 5.

import { dirname, join } from 'node:path';
import { fileURLToPath } from 'node:url';

import express from 'express';
import initFileRouter from 'express-file-routing';

const __dirname = dirname(fileURLToPath(import.meta.url));

const app = express();
await initFileRouter(app, { directory: join(__dirname, 'routes') });

app.listen(port, () => {
	console.log(`Server is running on http://localhost:${port}`);
});

Then, in my routes folder I have loads of different routes, and I put the following file anywhere within my routes folder:

// I tried routes/[...catchall].ts, routes/api/[...catchall].ts, etc etc etc...
import type { Request, Response } from 'express';

export default async function (req: Request, res: Response) {
    const path = req.params[0]

	res.json({
		path
	});
}

Upon server start I now get an error. It always looks the same, except for the number shown after Missing parameter name at, which changes based on the position of the [...catchall].ts file in the routes folder.

TypeError: Missing parameter name at 2: https://git.new/pathToRegexpError
    at name (/home/user/fantome/fantome/node_modules/.pnpm/path-to-regexp@8.2.0/node_modules/path-to-regexp/dist/index.js:73:19)
    at lexer (/home/user/fantome/fantome/node_modules/.pnpm/path-to-regexp@8.2.0/node_modules/path-to-regexp/dist/index.js:91:27)
    at lexer.next (<anonymous>)
    at Iter.peek (/home/user/fantome/fantome/node_modules/.pnpm/path-to-regexp@8.2.0/node_modules/path-to-regexp/dist/index.js:106:38)
    at Iter.tryConsume (/home/user/fantome/fantome/node_modules/.pnpm/path-to-regexp@8.2.0/node_modules/path-to-regexp/dist/index.js:112:28)
    at Iter.text (/home/user/fantome/fantome/node_modules/.pnpm/path-to-regexp@8.2.0/node_modules/path-to-regexp/dist/index.js:128:30)
    at consume (/home/user/fantome/fantome/node_modules/.pnpm/path-to-regexp@8.2.0/node_modules/path-to-regexp/dist/index.js:152:29)
    at parse (/home/user/fantome/fantome/node_modules/.pnpm/path-to-regexp@8.2.0/node_modules/path-to-regexp/dist/index.js:183:20)
    at /home/user/fantome/fantome/node_modules/.pnpm/path-to-regexp@8.2.0/node_modules/path-to-regexp/dist/index.js:294:74
    at Array.map (<anonymous>)

Am I doing something wrong?

[matthiaaas]

hi @lexisother, thank you for raising an issue. This problem doesn't arise for Express v4, right? On a first look, it seems to be related to a breaking change of path-to-regexp https://github.com/pillarjs/path-to-regexp#errors.

[lexisother]

Correct, the problem doesn't exist on Express 4.

[lexisother]

Just bumping this to make sure it wasn't forgotten. Anything that can be done about this? @matthiaaas

[matthiaaas]

hi @lexisother, thank you for the reminder. Yes, can you try the following version 3.2.0-alpha.0 with npm install express-file-routing@alpha.

It includes the following change for transforming the path into the regexp:

// Old
convertCatchallSyntax("/posts/:...catchall") -> "/posts/*"

// New
convertCatchallSyntax("/posts/:...catchall") -> "/posts/{*catchall}"

Unfortunately, this is not backwards compatible with Express <v4, so probably, this requires some sort of hacky runtime Express version check.

Let me know if that fix works for your Express v5 project. For a stable backwards compatible release further discussion is necessary. I am open for ideas on clean solutions to this.