Hi there,

I've encountered an issue when using express-openapi with my Express.js application. This application was based on a fresh installation.

The error I'm facing is as follows:

C:\Users\Alex\Visual Studio Code\TestProject\CustomerService\api\node_modules\express\node_modules\path-to-regexp\index.js:128
  return new RegExp(path, flags);
         ^

SyntaxError: Invalid regular expression: /^\/customer\(?:([^\/]+?))\/?$/: Unmatched ')'

This error occurs when my application is starting up.

Here is my project structure:

C:.
│   app.js
│   package-lock.json
│   package.json
│
├───api
│   │   api-doc.js
│   │
│   └───paths
│       │   test.js
│       │
│       └───customer
│               customer.js
│               {id}.js
│
└───bin
        www

Here is my package.json

{
  "name": "customer-service",
  "version": "0.0.0",
  "private": true,
  "scripts": {
    "node": "nodemon app.js",
    "start": "node ./bin/www"
  },
  "dependencies": {
    "cookie-parser": "~1.4.4",
    "debug": "~4.3.4",
    "dotenv": "^16.0.3",
    "express": "~4.18.2",
    "express-openapi": "^12.1.1",
    "morgan": "~1.10.0",
    "nodemon": "^2.0.20",
    "swagger-ui-express": "^4.6.1"
  }
}

Here is my code for the test.js, customer.js, and customer/{id}.js

module.exports = function () {
    let operations = {
        GET,
    };

    async function GET(req, res, next) {
        console.log("IN GET")
        console.log("REQUEST:", req)
        try {
            res.status(200).send();
        } catch (err) {
            console.error(err);
            res.status(500).json({
                error: "Internal Server Error"
            });
        }
    }

    GET.apiDoc = {
        summary: "Retrieve data from the api",
        operationId: "get-test",
        responses: {
            200: {
                description: "Returns if it was able to connect to the service",
            },
            500: {
                description: "Internal Server Error",
                content: {
                    "application/json": {
                        schema: {
                            $ref: "#/components/schemas/Error",
                        },
                    },
                },
            },
        },
    };
    return operations;
};

I am following the guidelines mentioned in the express-openapi documentation to structure my path files and use the {id} syntax for URL parameters.

Interestingly, I can access the /test route without any issues. However, I am not able to access the /customer by itself. I receive a 404 error. When adding the /customer/{id} file I receive the error detailed above.

The error seems to be related to the path-to-regexp module, but I'm not directly using this module in my code. It's being used internally by express-openapi.

I suspect the issue is due to the {id} file name, which could be getting passed as a part of the path to the path-to-regexp function.

If you could help me understand what's causing this error and how I could resolve it, I would greatly appreciate it. Please let me know if you need any further information. If you know better ways to debug this code or get a better error message, please let me know.

Thank you for your time and assistance!