lynx-admin-ui/src/middlewares/permission.middleware.ts

this module adds annotations for entities in order to automatically generate an Administration UI

import { BaseMiddleware, BLOCK_CHAIN } from 'lynx-framework/base.middleware';
import { Middleware } from 'lynx-framework/decorators';
import { Request, Response } from 'express';
import AdminUIModule from '..';

/**
 *
 * @param url
 * @returns name of enitity
 */
function getEntityName(url: string): string {
    const regex = /(adminUI\/)(ajaxRequest\/|ajaxDetails\/)?(\w*)/;
    const match = url.match(regex);

    if (null === match) {
        return 'unknown';
    }

    return match[3];
}

@Middleware('/adminUI/*')
export default class PermissionMiddleware extends BaseMiddleware {
    async apply(req: Request, res: Response) {
        const entityName = getEntityName(req.originalUrl);
        const method = req.method;
        let canAccess;

        switch (method) {
            case 'GET':
                canAccess = AdminUIModule.canReadFunction(req, entityName);
                break;
            case 'POST':
                canAccess = AdminUIModule.canWriteFunction(req, entityName);
                break;
            default:
                canAccess = false;
        }

        if (false === canAccess) {
            AdminUIModule.permissionDeniedHandler(req, res, entityName);
            return BLOCK_CHAIN;
        }
    }
}