laravel框架底层解析

本文参考陈昊《Laravel框架关键技术解析》，搭建一个属于自己的简化版服务容器。

laravel服务容器

1. 建立项目空文件夹（如 mylaravel）

2. 添加composer.json，执行composer install

{    "name": "laravel/laravel",    "description": "The Laravel Framework.",    "keywords": ["framework", "laravel"],    "license": "MIT",    "type": "project",    "autoload": {        "classmap": [        ],        "psr-4": {            "App\\": "app/"        }    }}

目的是为了学习、利用composer的自动加载。

1. 文件路径如下所示

• mylaravel

  • app

    • Traveller

      • Traveller.php

    • Visit

      • Leg.php

      • Visit.php

    • Container.php

    • Index.php

  • vendor

  • composer.json

1. 简化版Container.php

    getClosure($abstract, $concrete);        }            $this->bindings[$abstract] = compact('concrete', 'shared');        }    //默认的回调函数    protected function getClosure($abstract, $concrete)    {        //生成实例的回调函数， $c一般为ioc容器对象        return function($c) use ($abstract, $concrete)        {            $method = ($abstract == $concrete) ? 'build' : 'make';            return $c->$method($concrete);        };    }    //生成实例对象，首先解决接口和要实例化类之间的依赖    public function make($abstract)    {        $concrete = $this->getConcrete($abstract);        if ($this->isBuildable($concrete, $abstract)) {            $object = $this->build($concrete);        } else {            $object = $this->make($concrete);        }        return $object;    }    protected function isBuildable($concrete, $abstract)    {        return $concrete === $abstract || $concrete instanceof \Closure;    }    //获取绑定的回调函数    protected function getConcrete($abstract)    {        if ( ! isset($this->bindings[$abstract]))        {            return $abstract;        }        return $this->bindings[$abstract]['concrete'];    }    //实例化对象    public function build($concrete)    {        if ($concrete instanceof \Closure) {            return $concrete($this);        }        $reflector = new \ReflectionClass($concrete);        if ( ! $reflector->isInstantiable()) {            echo $message = "Target [$concrete] is not instantiable.";        }        $constructor = $reflector->getConstructor();        if (is_null($constructor)) {            return new $concrete;        }        $dependencies = $constructor->getParameters();        $instances = $this->getDependencies($dependencies);        return $reflector->newInstanceArgs($instances);    }    protected function getDependencies($parameters)    {        $dependencies = [];        foreach ($parameters as $parameter)        {            $denpendency = $parameter->getClass();            if (is_null($denpendency)) {                $dependencies[] = NULL;            } else {                $dependencies[] = $this->resolveClass($parameter);            }        }        return (array) $dependencies;    }    protected function resolveClass(\ReflectionParameter $parameter)    {        return $this->make($parameter->getClass()->name);    }}

Visit.php接口

Leg.php接口的一种实现

Traveller.php相当于Controller下的方法

    trafficTool = $visit;    }    public function visitTibet()    {        $this->trafficTool->go();    }}

Index.php

    bind('App\Visit\Visit', '\App\Visit\Leg');            $app->bind('Traveller', '\App\Traveller\Traveller');            //通过容器实现依赖注入，完成类的实例化            $tra = $app->make("\App\Traveller\Traveller");            $tra->visitTibet();    }}$b = new Index;$b->index();