Middlewares

There are basically 2 ways to manage middleware, legacy and modern.

---

Legacy mode only allowed intercepting the incoming request and send/manage a response from there and then, see below -

1. Direct:

   appExpress.middleware((request, response, log) => {
     log('Requested Path:', request.path);
   });

2. Using variable:

   // middlewares/analytics.js
   export const analyticsMiddleware = (request, response, log, error) => {
     // Implement analytics logic here
     try {
         analyticsSingleton.log('path', request.path);
         log(`logged a ${request.path} to analytics!`);
     } catch (err) {
         error(`Error logging to analytics: ${err.message}`);
     }
   };
   
   // index.js
   import analytics from './middlewares/analytics.js';
   appExpress.middleware(analytics);

3. Exiting the Middleware chain:

   appExpress.middleware((request, response, log) => {
     const { userJwtToken } = request.body;
     const isConsole = request.path.includes('/console');
   
     if (isConsole && !userJwtToken) {
         throw Error('No JWT Token found, aborting the requests.');
     }
   });

Note: Middlewares are processed in the order they are added.

---

Modern mode allows you to intercept the incoming request as well as the final processed response, see below -

appExpress.middleware({
  incoming: (request, response, log, error) => {},
  outgoing: (request, interceptor, log, error) => {
    // interceptor includes processed
    // `body`, headers, and statusCode which you can modify!
  }
});

Depending on your use-case, you can use either extend incoming, or outgoing or both.

---

Note: Legacy and modern mode are both compatible with the latest version of AppExpress!