4.用户可以对话题进行回复

• 本系列文章为laracasts.com 的系列视频教程——Let's Build A Forum with Laravel and TDD 的学习笔记。若喜欢该系列视频，可去该网站订阅后下载该系列视频， 支持正版 ；
• 视频源码地址：github.com/laracasts/Lets-Build-a-...；
• 本项目为一个 forum（论坛）项目，与本站的第二本实战教程 《Laravel 教程 - Web 开发实战进阶》 类似，可互相参照。

本节说明

对应视频第 4 小节：A User May Response To Threads

本节内容

上节中我们的..\views\threads\show.blade.php视图文件回复区域的内容为：

. . <div class="row"> <div class="col-md-8 col-md-offset-2"> @foreach ($thread->replies as $reply) <div class="panel panel-default"> <div class="panel-heading"> {{ $reply->owner->name }} 回复于 {{ $reply->created_at->diffForHumans() }} </div> <div class="panel-body"> {{ $reply->body }} </div> </div> @endforeach </div> </div> . . 

为了便于维护，我们将回复区域抽离成一个单独的视图。修改如下：

. . <div class="row"> <div class="col-md-8 col-md-offset-2"> @foreach ($thread->replies as $reply) @include('threads.reply') @endforeach </div> </div> . .

新建..\views\threads\reply.blade.php视图文件：

<div class="panel panel-default"> <div class="panel-heading"> <a href="#"> {{ $reply->owner->name }} </a> 回复于 {{ $reply->created_at->diffForHumans() }} </div> <div class="panel-body"> {{ $reply->body }} </div> </div>

我们可以给话题的内容加上作者的信息：
..\views\threads\show.blade.php

. . <div class="row"> <div class="col-md-8 col-md-offset-2"> <div class="panel panel-default"> <div class="panel-heading"> <a href="#">{{ $thread->creator->name }}</a> 发表了： {{ $thread->title }} </div> <div class="panel-body"> {{ $thread->body }} </div> </div> </div> </div> . .

我们需要先行编写单元测试，用来测试$thread->creator。但是在此之前，由于上一节中我们使用了$thread->replies来获取回复，但并未编写单元测试。现在补上单元测试，首先移除Unit文件夹下的示例文件，并新建单元测试文件：

$ php artisan make:test ThreadTest --unit

修改如下：

<?php namespace Tests\Unit; use Tests\TestCase; use Illuminate\Foundation\Testing\DatabaseMigrations; class ThreadTest extends TestCase { use DatabaseMigrations; /** @var Thread $thread */ protected $thread; public function setUp() { parent::setUp(); $this->thread = factory('App\Thread')->create(); } /** @test */ public function a_thread_has_replies() { $this->assertInstanceOf('Illuminate\Database\Eloquent\Collection',$this->thread->replies); } } 

测试一下：

$ phpunit tests/Unit/ThreadTest.php

测试通过：

继续编写$thread->creator的测试代码：
ThreadTest.php

. . /** @test */ public function a_thread_has_a_creator() { $this->assertInstanceOf('App\User',$this->thread->creator); } }

我们可以使用--filter来单独测试：

$ phpunit --filter a_thread_has_a_creator

因为我们还未进行模型关联：
app\Thread.php

. . public function creator() { return $this->belongsTo(User::class,'user_id'); // 使用 user_id 字段进行模型关联 } . .

再次测试即可通过，刷新页面即可看到效果：

接下来新建测试：

$ php artisan make:test ParticipateInForumTest

先编写测试逻辑：

<?php namespace Tests\Feature; use Tests\TestCase; use Illuminate\Foundation\Testing\DatabaseMigrations; class ParticipateInForumTest extends TestCase { use DatabaseMigrations; /** @test */ function an_authenticated_user_may_participate_in_forum_threads() { // Given we have a authenticated user // And an existing thread // When the user adds a reply to the thread // Then their reply should be visible on the page } } 

再填充具体代码：

<?php namespace Tests\Feature; use Tests\TestCase; use Illuminate\Foundation\Testing\DatabaseMigrations; class ParticipateInForumTest extends TestCase { use DatabaseMigrations; /** @test */ function an_authenticated_user_may_participate_in_forum_threads() { // Given we have a authenticated user $this->be($user = factory('App\User')->create()); // And an existing thread $thread = factory('App\Thread')->create(); // When the user adds a reply to the thread $reply = factory('App\Reply')->create(); $this->post($thread->path().'/replies',$reply->toArray()); // Then their reply should be visible on the page $this->get($thread->path()) ->assertSee($reply->body); } } 

注意到我们使用$thread->path()来获取 URL ，想起在ReadThreadsTest.php文件中可进行优化：
tests\Feature\ReadThreadsTest.php

. . /** @test */ public function a_user_can_read_a_single_thread() { $this->get($this->thread->path()) //此处 ->assertSee($this->thread->title); } /** @test */ public function a_user_can_read_replies_that_are_associated_with_a_thread() { // 如果有 Thread // 并且该 Thread 有回复 $reply = factory('App\Reply') ->create(['thread_id' => $this->thread->id]); // 那么当我们看 Thread 时 // 我们也要看到回复 $this->get($this->thread->path()) //还有此处 ->assertSee($reply->body); } . .

一般而言，当修改已通过的测试时，应该在修改之后（需注释新建的测试）再次测试，确保之前的测试逻辑未被破坏。

$ phpunit

当我们测试新写的测试时：

$ phpunit tests/Feature/ParticipateInForumTest.php

会得到一大段长长的报错信息，要定位到错误十分困难：

在app\Exceptions\Handler.php中加上一行：

. . public function render($request, Exception $exception) { if(app()->environment() === 'local') throw $exception; // 此处加上一行 return parent::render($request, $exception); } . .

注1：视频教程中使用的是app()->environment() === 'testing'，但经过测试未生效，遂改为以上local。

再次运行测试：

$ phpunit tests/Feature/ParticipateInForumTest.php

现在可以十分容易地定位错误：

添加路由：

Route::post('/threads/{thread}/replies','RepliesController@store');

前往RepliesController增加store方法：

<?php namespace App\Http\Controllers; use App\Thread; use Illuminate\Http\Request; class RepliesController extends Controller { public function store(Thread $thread) { $thread->addReply([ 'body' => request('body'), 'user_id' => auth()->id(), ]); return back(); } } 

为store方法添加单元测试：
ThreadTest.php

<?php namespace Tests\Unit; use Tests\TestCase; use Illuminate\Foundation\Testing\DatabaseMigrations; class ThreadTest extends TestCase { use DatabaseMigrations; protected $thread; public function setUp() { parent::setUp(); // TODO: Change the autogenerated stub $this->thread = factory('App\Thread')->create(); } /** @test */ public function a_thread_has_replies() { $this->assertInstanceOf('Illuminate\Database\Eloquent\Collection',$this->thread->replies); } /** @test */ public function a_thread_has_a_creator() { $this->assertInstanceOf('App\User',$this->thread->creator); } /** @test */ public function a_thread_can_add_a_reply() { $this->thread->addReply([ 'body' => 'Foobar', 'user_id' => 1 ]); $this->assertCount(1,$this->thread->replies); } } 

测试一下：

添加addReply()方法：
app\Thread.php

. . public function addReply($reply) { $this->replies()->create($reply); } . .

再次运行测试

$ phpunit --filter an_authenticated_user_may_participate_in_forum_threads

结果报错：

按道理说不应该，根据查阅到的资料，在测试环境应该是不会检验CsrfToken。尝试了诸多办法仍旧无法解决，故采用以下形式进行测试：

$ APP_ENV=testing phpunit --filter an_authenticated_user_may_participate_in_forum_threads

即：在运行测试的时候将环境设为testing，为配合使用，应将Handler.php文件中代码改为如下：

. . public function render($request, Exception $exception) { if (app()->environment() === 'testing') throw $exception; return parent::render($request, $exception); } . .

运行测试：

运行完整测试：

$ APP_ENV=testing phpunit

注1：此处在课后附注有详细解释。

我们限制只有登录用户才能添加回复，只需利用auth中间件即可：
RepliesController.php

public function __construct() { $this->middleware('auth'); } . .

测试如果我们将单元测试代码更改一下：
ParticipateInForumTest.php

<?php namespace Tests\Feature; use Tests\TestCase; use Illuminate\Foundation\Testing\DatabaseMigrations; class ParticipateInForumTest extends TestCase { use DatabaseMigrations; /** @test */ function an_authenticated_user_may_participate_in_forum_threads() { // Given we have a authenticated user // $this->be($user = factory('App\User')->create()); // 已登录用户 $user = factory('App\User')->create(); // 未登录用户 // And an existing thread $thread = factory('App\Thread')->create(); // When the user adds a reply to the thread $reply = factory('App\Reply')->create(); $this->post($thread->path() .'/replies',$reply->toArray()); // 注：此处有修改 // Then their reply should be visible on the page $this->get($thread->path()) ->assertSee($reply->body); } } 

再次运行测试：

$ APP_ENV=testing phpunit

提示用户未认证，说明我们的测试有效。接下来再建立一个测试，测试未登录用户不能添加回复：
ParticipateInForumTest.php

<?php namespace Tests\Feature; use Tests\TestCase; use Illuminate\Foundation\Testing\DatabaseMigrations; class ParticipateInForumTest extends TestCase { use DatabaseMigrations; /** @test */ public function unauthenticated_user_may_not_add_replies() { $this->expectException('Illuminate\Auth\AuthenticationException'); $thread = factory('App\Thread')->create(); $reply = factory('App\Reply')->create(); $this->post($thread->path().'/replies',$reply->toArray()); } /** @test */ function an_authenticated_user_may_participate_in_forum_threads() { // Given we have a authenticated user $this->be($user = factory('App\User')->create()); // And an existing thread $thread = factory('App\Thread')->create(); // When the user adds a reply to the thread $reply = factory('App\Reply')->create(); $this->post($thread->path() .'/replies',$reply->toArray()); // Then their reply should be visible on the page $this->get($thread->path()) ->assertSee($reply->body); } } 

再次测试：

$ APP_ENV=testing phpunit

成功通过：

实际上，测试未登录用户的代码可以更加简单，因为我们实际上只用测试未登录用户是否抛出异常即可：
ParticipateInForumTest.php

. . /** @test */ public function unauthenticated_user_may_not_add_replies() { $this->expectException('Illuminate\Auth\AuthenticationException'); $this->post('threads/1/replies',[]); } . .

最后，需要修改一下an_authenticated_user_may_participate_in_forum_threads：

. . /** @test */ function an_authenticated_user_may_participate_in_forum_threads() { // Given we have a authenticated user $this->be($user = factory('App\User')->create()); // And an existing thread $thread = factory('App\Thread')->create(); // When the user adds a reply to the thread $reply = factory('App\Reply')->make(); // -->此处有修改 $this->post($thread->path() .'/replies',$reply->toArray()); // Then their reply should be visible on the page $this->get($thread->path()) ->assertSee($reply->body); } . .

注2：详见课后附注处。

课后附注

• 关于注1的说明：
  第四节课经历比较坎坷，主要是遇到了一个问题：
  

  Illuminate\Session\TokenMismatchException:

  显示的问题应该是CSRF令牌不符，于是定位到
  \vendor\laravel\framework\src\Illuminate\Foundation\Http\Middleware\VerifyCsrfToken.php的tokensMatch方法：

  protected function tokensMatch($request) { $token = $this->getTokenFromRequest($request); return is_string($request->session()->token()) && is_string($token) && hash_equals($request->session()->token(), $token); }

  发现验证的是$token跟$request->session()->token()的值，于是将两者的值打印出来：

  protected function tokensMatch($request) { $token = $this->getTokenFromRequest($request); var_dump($token); var_dump($request->session()->token());exit; return is_string($request->session()->token()) && is_string($token) && hash_equals($request->session()->token(), $token); }

  运行：

  $ phpunit

  
  本以为问题就是因为$token的值是null，然而在看了文章 防范 CSRF 跨站请求伪造-以 Laravel 中间件 VerifyCSRFToken 为例 再结合代码发现，在进行测试时是不需要验证CsrfToken的：
  \vendor\laravel\framework\src\Illuminate\Foundation\Http\Middleware\VerifyCsrfToken.php：

  . . public function handle($request, Closure $next) { if ( $this->isReading($request) || $this->runningUnitTests() || $this->inExceptArray($request) || $this->tokensMatch($request) ) { return $this->addCookieToResponse($request, $next($request)); } throw new TokenMismatchException; } . .

  其中的第二条，$this->runningUnitTests()即意味着在测试时应该放行。于是追溯runningUnitTests方法：

  protected function runningUnitTests() { return $this->app->runningInConsole() && $this->app->runningUnitTests(); }

  经过验证，$this->app->runningInConsole()为true。于是接着追溯runningUnitTests方法：

  public function runningUnitTests() { return $this['env'] == 'testing'; }

  然后验证到$this['env']的值为local，终于定位到错误：运行测试时的环境为local。令人疑惑的是，phpunit.xml的配置与教程相同，但不知为何没有生效：
  phpunit.xml

  <phpunit backupGlobals="false" backupStaticAttributes="false" bootstrap="bootstrap/autoload.php" colors="true" convertErrorsToExceptions="true" convertNoticesToExceptions="true" convertWarningsToExceptions="true" processIsolation="false" stopOnFailure="false"> <testsuites> <testsuite name="Feature"> <directory suffix="Test.php">./tests/Feature</directory> </testsuite> <testsuite name="Unit"> <directory suffix="Test.php">./tests/Unit</directory> </testsuite> </testsuites> <filter> <whitelist processUncoveredFilesFromWhitelist="true"> <directory suffix=".php">./app</directory> </whitelist> </filter> <php> <env name="APP_ENV" value="testing"/> -->此处将环境设置为 testing，但未生效 <env name="DB_CONNECTION" value="sqlite"/> <env name="DB_DATABASE" value=""/> <env name="CACHE_DRIVER" value="array"/> <env name="SESSION_DRIVER" value="array"/> <env name="QUEUE_DRIVER" value="sync"/> </php> </phpunit>

• 关于注2的说明：
  先来看一下create()与make()方法的说明：

  /** * Create a collection of models and persist them to the database. * * @param array $attributes * @return mixed */ public function create(array $attributes = []) { $results = $this->make($attributes); if ($results instanceof Model) { $this->store(collect([$results])); } else { $this->store($results); } return $results; }

  /** * Create a collection of models. * * @param array $attributes * @return mixed */ public function make(array $attributes = []) { if ($this->amount === null) { return $this->makeInstance($attributes); } if ($this->amount < 1) { return (new $this->class)->newCollection(); } return (new $this->class)->newCollection(array_map(function () use ($attributes) { return $this->makeInstance($attributes); }, range(1, $this->amount))); }

  create()方法会得到一个实例，并将实例保存到数据库中；make()方法只会得到一个实例。在本节的测试中我们不需要保存$thread实例，因为我们会在RepliesController的store()方法进行保存，故使用make()方法。

  另外，create()与make()方法的区别可以参见这篇文章 What does the make() method do in Laravel