Dynamic Routing on Express JS

routes.ts

import express, { Response, Request } from 'express';
import fs from 'fs';
import { IRouterSettings } from './interfaces/IRouterSettings';
import Logger from './utils/logger';

const router = express.Router();

// loop through all the routes
const controllersPath = `${__dirname}/controllers`;
const controllers = fs.readdirSync(controllersPath);
controllers.forEach(async controller => {
  try {
    // router settings path
    const routeSettingsPath = `${__dirname}/controllers/${controller}/router.json`;
    const routeFile = fs.readFileSync(routeSettingsPath, 'utf8');

    if (!routeFile) {
      return;
    }

    // Read the route settings
    const json = JSON.parse(routeFile) as IRouterSettings;

    // iterate all paths from json
    json.routes.forEach(route => {
      const path = `${json.prefix}/${route.path}`.replace(/\/\//g, '/');
      Logger.info(`[Router] Adding route ${path}`);
      // remove trailing slash
      const handler = route.handler.split('.');
      const controllerFile = handler[0];
      const methodName = handler[1];

      // create router
      router.use(path, async (req: Request, res: Response) => {
        // Check method
        if (req.method !== route.method) {
          return res.status(405).json({
            message: `Method ${req.method} not allowed`,
          });
        }

        try {
          // eslint-disable-next-line global-require
          const ControllerModule = require(`${__dirname}/controllers/${controller}/${controllerFile}`);
          console.log('controller class', ControllerModule);
          // check if Controller Module is a class
          if (typeof ControllerModule !== 'function') {
            return res.status(500).json({
              message: `${controllerFile} is not a class`,
            });
          }

          const controllerInstance = new ControllerModule(req, res);

          // check if function exists on ControllerModule
          if (!controllerInstance[methodName]) {
            return res.status(404).json({
              message: `Method ${methodName} not found`,
            });
          }

          return controllerInstance[methodName]();
        } catch (error) {
          return res.status(500).json({
            message: `${controller} Something went wrong`,
          });
        }
      });
    });

    // console.log(controller);
    // console.log(json);
  } catch (error) {
    Logger.error(`Error on ${controller} no router.json found`);
  }
});

export default router;