【发布时间】：2020-02-21 14:14:24
【问题描述】：
我正在学习 lumen，从未使用过它或它的大哥 laravel。 不过，我编写“vanilla”PhP 代码大约有 1 1/2 年，例如，我熟悉 PDO 请求的功能。
所以我正在使用本教程： https://www.youtube.com/watch?v=6Oxfb_HNY0U
在我创建了迄今为止只有 6 列的“文章”表的数据库后，我尝试了教程中的以下代码：
web.php（位于“routes”文件夹内）：
<?php
/*
|--------------------------------------------------------------------------
| Application Routes
|--------------------------------------------------------------------------
|
| Here is where you can register all of the routes for an application.
| It is a breeze. Simply tell Lumen the URIs it should respond to
| and give it the Closure to call when that URI is requested.
|
*/
$router->get('/', function () use ($router) {
return $router->app->version();
});
$router->group(['prefix' => 'api'], function($router){
$router->get('articles', 'ArticleController@showAllArticles');
});
$router->get('foo', function () {
return 'Hello World';
});
$router->post('foo', function () {
//
});
app.php（位于“bootstrap”内）：
<?php
require_once __DIR__.'/../vendor/autoload.php';
(new Laravel\Lumen\Bootstrap\LoadEnvironmentVariables(
dirname(__DIR__)
))->bootstrap();
/*
|--------------------------------------------------------------------------
| Create The Application
|--------------------------------------------------------------------------
|
| Here we will load the environment and create the application instance
| that serves as the central piece of this framework. We'll use this
| application as an "IoC" container and router for this framework.
|
*/
$app = new Laravel\Lumen\Application(
dirname(__DIR__)
);
// $app->withFacades();
$app->withEloquent();
/*
|--------------------------------------------------------------------------
| Register Container Bindings
|--------------------------------------------------------------------------
|
| Now we will register a few bindings in the service container. We will
| register the exception handler and the console kernel. You may add
| your own bindings here if you like or you can make another file.
|
*/
$app->singleton(
Illuminate\Contracts\Debug\ExceptionHandler::class,
App\Exceptions\Handler::class
);
$app->singleton(
Illuminate\Contracts\Console\Kernel::class,
App\Console\Kernel::class
);
/*
|--------------------------------------------------------------------------
| Register Middleware
|--------------------------------------------------------------------------
|
| Next, we will register the middleware with the application. These can
| be global middleware that run before and after each request into a
| route or middleware that'll be assigned to some specific routes.
|
*/
// $app->middleware([
// App\Http\Middleware\ExampleMiddleware::class
// ]);
// $app->routeMiddleware([
// 'auth' => App\Http\Middleware\Authenticate::class,
// ]);
/*
|--------------------------------------------------------------------------
| Register Service Providers
|--------------------------------------------------------------------------
|
| Here we will register all of the application's service providers which
| are used to bind services into the container. Service providers are
| totally optional, so you are not required to uncomment this line.
|
*/
// $app->register(App\Providers\AppServiceProvider::class);
// $app->register(App\Providers\AuthServiceProvider::class);
// $app->register(App\Providers\EventServiceProvider::class);
/*
|--------------------------------------------------------------------------
| Load The Application Routes
|--------------------------------------------------------------------------
|
| Next we will include the routes file so that they can all be added to
| the application. This will provide all of the URLs the application
| can respond to, as well as the controllers that may handle them.
|
*/
$app->router->group([
'namespace' => 'App\Http\Controllers',
], function ($router) {
require __DIR__.'/../routes/web.php';
});
return $app;
Article.php（位于“app”文件夹内）：
<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Article extends Model
{
protected $fillable = [
'title', 'description','status'
];
}
ArticleController.php（位于 \Http\Controllers 中）
<?php
namespace App\Http\Controllers;
use App\Article;
use Illuminate\Http\Requests;
class ArticleController extends Controller
{
/**
* Create a new controller instance.
*
* @return void
*/
public function __construct()
{
//
}
//
public function showAllArticles(){
return response()->json(Article::all());
}
}
现在令人困惑的是这个语法是如何工作的：
return response()->json(Article::all());
来自 ArticleController.php。
据我了解，对该函数的调用已在 web.php 中定义为：
$router->group(['prefix' => 'api'], function($router){
$router->get('articles', 'ArticleController@showAllArticles');
});
在这里，定义了要访问的表，然后还定义了处理来自 DB 的响应的函数。 到目前为止，我认为我很“好”。
但是当我现在尝试将这个框架语法“翻译”成它的 PHP 关联时，我感到困惑。 做什么：
Article::all()
里面
return response()->json(Article::all());
做吗？ 什么是文章？我想这是表格文章中的一行。这里的命名是任意的，不是吗？ 然后是“所有（）”。 我想到的第一个猜测是等效于 PDO 的“fetchAll()”。 真的吗？如果我在基于 PDO 的数据库查询中使用 fetchAll()，行为是否相同？ 语法本身有点直观，但它仍然为不同的解释留下了空间。 由于我认为是响应中的单行的 Article 被“管道”到“all()”函数，所以 all() 也可以做一些不同于“fetchAll()”的事情，后者总是应用于查询的完整结果，而不仅仅是单个结果集 (=row)。
此外，有人知道 Lumen 的好教程吗？ 仅使用官方文档真的很糟糕，因为框架是如此模块化，只是阅读不同的部分并不能帮助我建立一个小型测试项目，从中我可以学习如何实际使用框架，而不仅仅是描述它......
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