Introduction

Nimo helps you to organize your middlewares (and handlers).

Installation

composer require litphp/nimo

MiddlewarePipe

Pipe middlewares one after another, is the essential part of middleware pattern. And it's the core infrastructure of nimo.

$pipe = new MiddlewarePipe();

$pipe->append($middleware); // append $middleware to last of the pipeline

$pipe->prepend($middleware2); // also you can do prepend

Thanks to our MiddlewareTrait, you can invoke prepend and append on any middleware instance provided by us. (or yours, just use the trait)

$first = new NoopMiddleware();

$first->append($second); // same as (new MiddlewarePipe())->append($first)->append($second)

$next passed to middleware

Prior to 0.9.1 the MiddlewarePipe is implemented with a mutable state inside. If any middleware call $next more than one times, the behavior will be unreasonable (it increase inner $index and try to call the middleware at that index).

Start from 0.9.1, the state is immutable, makes calling $next always to invoke remaining stack of middleware(s) as expected. This can be useful for retry logic or fallback logic.

If you are implementing some middleware, be careful to keep request related state in request object only. Don't save any request state in middleware object or calling $next twice may be broken due to leaked state.

Dummys

There are some basic middleware/handlers with straightforward behavior.

• NoopMiddleware: middleware doing nothing but delegate to the handler
• FixedResponseMiddleware: never call handler, just return that fixed response
• FixedResponseHandler: just return that fixed response
• CallableHandler: wraps a callable with signature (RequestInterface): ResponseInterface
• MiddlewareIncludedHandler: include a middleware into a handler (HandlerTrait::includeMiddleware helps you do this directly on handler instance)