1、 lumen(5.6) 中間件 類型
lumen 中的中間件份為兩種(bootstrap/app.php) ：
(1 全局中間件
<?php
$app->middleware([
App\Http\Middleware\ExampleMiddleware::class
]);
(2 路由中間件 (需分配到route中)
<?php
$app->routeMiddleware([
'auth' => App\Http\Middleware\Authenticate::class,
]);
保存在 Concerns\RoutesRequests(vendor/laravel/lumen-framework/src/Concerns/RoutesRequests.php) 中
<?php
trait RoutesRequests
{
/**
* All of the global middleware for the application.
*
* @var array
*/
protected $middleware = [];
/**
* All of the route specific middleware short-hands.
*
* @var array
*/
protected $routeMiddleware = [];
........
2、請(qǐng)求過程
1)入口文件 (public/index.php)
<?php
$app = require __DIR__.'/../bootstrap/app.php';
$app->run();
// 簡單的兩行代碼
2)run()方法 Concerns\RoutesRequests(vendor/laravel/lumen-framework/src/Concerns/RoutesRequests.php)
<?php
trait RoutesRequests
{
......
public function run($request = null)
{
$response = $this->dispatch($request); // 處理請(qǐng)求 (中間件 等)
if ($response instanceof SymfonyResponse) {
$response->send(); // 返回 http 請(qǐng)求結(jié)果
} else {
echo (string) $response;
}
// 處理 middleware 中的 terminate() -->終止中間件 (有時(shí)候中間件可能需要在 HTTP 響應(yīng)發(fā)送到瀏覽器之后做一些工作)
if (count($this->middleware) > 0) {
$this->callTerminableMiddleware($response);
}
}
......
3) $this->dispatch($request) Concerns\RoutesRequests(vendor/laravel/lumen-framework/src/Concerns/RoutesRequests.php)
<?php
trait RoutesRequests
{
......
/**
* Dispatch the incoming request.
*
* @param SymfonyRequest|null $request
* @return Response
*/
public function dispatch($request = null)
{
// 初始化 $request
list($method, $pathInfo) = $this->parseIncomingRequest($request);
try {
// pipeline 處理 全局 中間件
return $this->sendThroughPipeline($this->middleware, function () use ($method, $pathInfo) {
if (isset($this->router->getRoutes()[$method.$pathInfo])) {
// handleFoundRoute() 處理 route中間件
return $this->handleFoundRoute([true, $this->router->getRoutes()[$method.$pathInfo]['action'], []]);
}
// 處理 沒有 路由到的 請(qǐng)求404
return $this->handleDispatcherResponse(
$this->createDispatcher()->dispatch($method, $pathInfo)
);
});
} catch (Exception $e) {
return $this->prepareResponse($this->sendExceptionToHandler($e));
} catch (Throwable $e) {
return $this->prepareResponse($this->sendExceptionToHandler($e));
}
}
......
4) $this->sendThroughPipeline(array $middleware, Closure $then) Concerns\RoutesRequests(vendor/laravel/lumen-framework/src/Concerns/RoutesRequests.php)
<?php
trait RoutesRequests
{
......
/**
* Send the request through the pipeline with the given callback.
*
* @param array $middleware
* @param \Closure $then
* @return mixed
*/
protected function sendThroughPipeline(array $middleware, Closure $then)
{
if (count($middleware) > 0 && ! $this->shouldSkipMiddleware()) {
// pipeline 實(shí)現(xiàn)中間件
return (new Pipeline($this))
->send($this->make('request'))
->through($middleware)
->then($then);
}
return $then();
}
......
3、pipeline 的實(shí)現(xiàn)過程
通過簡單例子
<?php
namespace App\Http\Controllers;
use Illuminate\Pipeline\Pipeline;
class TestController extends Controller{
function test(){
$pipes = [
function ($poster, $callback) {
$poster += 1;
return $callback($poster);
},
function ($poster, $callback) {
$result = $callback($poster);
return $result - 1;
},
function ($poster, $callback) {
$poster += 2;
return $callback($poster);
}
];
echo (new Pipeline())->send(0)->through($pipes)->then(function ($poster) {
return $poster;
}); // 執(zhí)行輸出為 2
}
}
->send($passable) 設(shè)置通過管道的對(duì)象
->through($pipes) 設(shè)置管道
->then($closure) 執(zhí)行$closure 并使對(duì)象通過管道
Pipeline 中then()源碼 重點(diǎn)在這個(gè)方法里面 (vendor/illuminate/pipeline/Pipeline.php)
<?php
......
/**
* Run the pipeline with a final destination callback.
*
* @param \Closure $destination
* @return mixed
*/
public function then(Closure $destination)
{
$pipeline = array_reduce(
array_reverse($this->pipes), $this->carry(), $this->prepareDestination($destination)
);
return $pipeline($this->passable);
}
......
/**
* Get the final piece of the Closure onion.
*
* @param \Closure $destination
* @return \Closure
*/
protected function prepareDestination(Closure $destination)
{
return function ($passable) use ($destination) {
return $destination($passable);
};
}
......
/**
* Get a Closure that represents a slice of the application onion.
*
* @return \Closure
*/
protected function carry()
{
return function ($stack, $pipe) {
return function ($passable) use ($stack, $pipe) {
if (is_callable($pipe)) {
// 如果管道是閉包的實(shí)例，我們將直接調(diào)用它，
// 但否則，我們將解決容器中的管道，并用適當(dāng)?shù)姆椒ê蛥?shù)調(diào)用它，將結(jié)果返回。
return $pipe($passable, $stack);
} elseif (! is_object($pipe)) {
list($name, $parameters) = $this->parsePipeString($pipe);
// 如果管道是字符串，我們將解析字符串并解析依賴注入容器中的類。
// 然后，我們可以構(gòu)建一個(gè)可調(diào)用的函數(shù)并執(zhí)行管道函數(shù)，以提供所需的參數(shù)。
$pipe = $this->getContainer()->make($name);
$parameters = array_merge([$passable, $stack], $parameters);
} else {
// 如果管道已經(jīng)是一個(gè)對(duì)象，我們只做一個(gè)可調(diào)用的，并將它傳遞給管道。
// 沒有必要進(jìn)行任何額外的解析和格式化，因?yàn)槲覀兯o出的對(duì)象已經(jīng)是一個(gè)完全實(shí)例化的對(duì)象。
$parameters = [$passable, $stack];
}
return method_exists($pipe, $this->method) // $this->method = 'handle';
? $pipe->{$this->method}(...$parameters)
: $pipe(...$parameters);
};
};
}
......
簡化 示例中的方法
<?php
$pipes = [$pipe1, $pipe2, $pipe3];
$passable = 0;
$destination = $closure4 = function ($poster) {
return $poster;
};
// 重點(diǎn) array_reduce 方法 ->用回調(diào)函數(shù)迭代地將數(shù)組簡化為單一的值
$pipeline = array_reduce([$pipe3, $pipe2, $pipe1], $closure, $closure5);
$closure5 = function ($passable) use ($destination) {
return $destination($passable);
}
$closure = function ($stack, $pipe) {
return function ($passable) use ($stack, $pipe) {
......
};
};
array_reduce、pipeline 執(zhí)行過程
pipeline執(zhí)行過程.png
說明： 例子中的pipe使用的是閉包而 lumen中使用的是 calss 或者是 sting=>class 所以在carry()方法里面的 對(duì)應(yīng)得是 if 后面的兩種情況 $poser 相當(dāng)于在lumen 中的$request ;$poster += 1; 和 $poster += 2; 就是件前操作 而 $result - 1; 就是件后操作了。最后 在$destination閉包中去處理 action 操作 ?。?/p>
