Define the behavior of a user-side middleware The middleware target will be called at the time of a request. onPreRequest(...args) will be called before executing the endpoint. onPostRequest(...args) will be called after executing the endpoint.

If onPreRequest returns false, the endpoint's execution will be ignored as well as the post-request middleware. In order to keep the execution cycle going, onPreRequest must return true. Although in almost all use cases returning true will sound logical, Identity verifications fit in the concept of returning false.

   export class MyMiddleware implements MiddlewareTarget {
       onPreRequest(@RequestParam() request: Request, @ResponseParam() response: any) {
           console.log("onPreRequest() called");
           return true;
       }

       onPostRequest() {
           console.log("onPostRequest() called");
       }
   }