WebHook

WebHook is proposed in Blade, you can call it hook. The main purpose of this component is to intercept some operations before and after each request.

Register WebHook

You can implement the WebHook interface and add a @Bean annotation to the implementation class to indicate that the class is being scanned by the IOC container.

@Bean
Public class Hook1 implements WebHook {

    @Override
    Public boolean before(RouteContext ctx) {
        System.out.println("Enter web hook1");
        Return true;
    }

}

Let’s see how the WebHook interface is defined:

@FunctionalInterface
Public interface WebHook {

    Boolean before(RouteContext ctx);

    Default boolean after(RouteContext ctx) {
        Return true;
    }

}

This uses Java8’s functional methods and provides a default after implementation, which is called after the route is executed if the after method is overridden. Here, the return value of WebHook determines whether this request continues to be called down. If it is true, it will be let go, and if false is returned, the request will be interrupted.

In addition to intercepting all requests, you can also choose to intercept some requests, such as intercepting all requests under /user, then you don’t need to use this global hook, you can do this:

Blade.of()
     .before("/user/*", ctx -> System.out.println("before: " + ctx.uri()))

Middleware

In the Blade, the hook is subdivided, that is, the middleware. Its execution logic is earlier than the previous hook, and is mainly used for pre-interception of some operations such as verification and authentication.

You can define a middleware like this:

Public class MyMiddleware implements WebHook {
    @Override
    Public boolean before(RouteContext context) {
        System.out.println("this is my middleware");
        Return true;
    }
}

Then use it

Blade.of().use(new MyMiddleware()).start(XXX);

At this point all requests will execute the contents of the middleware first, and then execute the logic (if any) in the hook.

Default middleware

Some middleware is built into the Blade:

• BasicAuthMiddleware: for Basic authentication
• CorsMiddleware: used to do Cors cross-domain homology
• XssMiddleware: used to filter XSS requests
• CsrfMiddleware: for CSRF defense

You can also define some middleware according to your needs. If you think they are generic, you can also consider open source for everyone to use.