const mixinafBedSheet::Middleware

afBedSheet::Middleware

Implement to define BedSheet middleware.

HTTP requests are funnelled through a stack of middleware instances until they reach a terminator. The default BedSheet terminator returns a 404 error.

Middleware may perform processing before and / or after passing the request down the pipeline to other middleware instances. Use middleware to address cross cutting concerns such as authentication and authorisation. See the FantomFactory article Basic HTTP Authentication With BedSheet for examples.

Because middleware effectively wrap other middleware instances and each can terminate the pipeline prematurely, the ordering of middleware is extremely important.

Route instances are processed in the Routes middleware. So generally you would explicitly contribute your own middleware to be before or after this.

IoC Configuration

Instances of Middleware should be contributed to the MiddlewarePipeline service.

For example, in your AppModule class:

@Contribute { serviceType=MiddlewarePipeline# }
Void contributeMiddleware(Configuration config) {
    config.set("MyMiddleware", config.build(MyMiddleware#)).before("afBedSheet.routes")
}

To list all middleware instances used by BedSheet (on startup), add the following to your IoC Module:

Void onRegistryStartup(Configuration config) {
    scope := config.scope
    config.set("logMiddleware", |->| {
        scope.serviceByType(MiddlewarePipeline#)->logMiddleware
    })
}

service

Source

abstract Void service(MiddlewarePipeline pipeline)

Call pipeline.service to allow other Middleware to further process the request:

const class MyMiddleware : Middleware {
    override Void service(MiddlewarePipeline pipeline) {
        ...
        ...
        // pass the request to other middleware for processing
        pipeline.service 
        ...
        ...
    }
}