Merge pull request #70 from krlxfm/profanity-rule

Add a profanity rule

app/Http/Requests/ShowUpdateRequest.php

@@ -3,6 +3,7 @@
 namespace KRLX\Http\Requests;
 
 use KRLX\Track;
+use KRLX\Rules\Profanity;
 use Illuminate\Foundation\Http\FormRequest;
 
 class ShowUpdateRequest extends FormRequest
@@ -49,7 +50,7 @@ protected function baseRules()
     {
         $baseRules = [
             'submitted' => ['boolean'],
-            'title' => ['string', 'min:3', 'max:200'],
+            'title' => ['string', 'min:3', 'max:200', new Profanity],
             'content' => ['array'],
             'scheduling' => ['array'],
             'conflicts' => ['array', 'min:0'],

app/Rules/Profanity.php

@@ -0,0 +1,117 @@
+<?php
+
+namespace KRLX\Rules;
+
+use Illuminate\Contracts\Validation\Rule;
+
+class Profanity implements Rule
+{
+    /**
+     * The word that has been found.
+     *
+     * @var string|null
+     */
+    public $word;
+
+    /**
+     * Create a new rule instance.
+     *
+     * @return void
+     */
+    public function __construct()
+    {
+        //
+    }
+
+    /**
+     * Determine if the validation rule passes.
+     *
+     * @param  string  $attribute
+     * @param  mixed  $value
+     * @return bool
+     */
+    public function passes($attribute, $value)
+    {
+        $target = preg_replace('/[@#\$%\^]/', '*', strtolower($value));
+        $words = explode(' ', $target);
+        foreach (array_merge(config('defaults.banned_words.full'), config('defaults.banned_words.partial')) as $bad_word) {
+            if (in_array($bad_word, $words) or in_array(str_plural($bad_word), $words)) {
+                $this->word = $bad_word;
+
+                return false;
+            }
+        }
+
+        return $this->partialWordsPass($target);
+    }
+
+    /**
+     * Check the partial words - these are words which could appear as they
+     * normally are, or in any number of creative derivatives.
+     *
+     * @param  mixed  $value
+     * @return bool
+     */
+    protected function partialWordsPass($value)
+    {
+        $bad_words = $this->assembleDerivatives();
+        foreach ($bad_words as $word => $derivatives) {
+            if (! $this->singleWordDerivativesPass($word, $derivatives, $value)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Check if a single word's derivatives show up.
+     *
+     * @param  string  $word
+     * @param  array  $derivatives
+     * @param  string  $value
+     * @return bool
+     */
+    private function singleWordDerivativesPass($word, $derivatives, $value)
+    {
+        foreach ($derivatives as $derivative) {
+            if (strpos($value, $derivative) !== false) {
+                $this->word = $word;
+
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Assemble the derivatives list used in partial word validation.
+     *
+     * @return array
+     */
+    protected function assembleDerivatives()
+    {
+        $bad_words = [];
+        foreach (config('defaults.banned_words.partial') as $bad_word) {
+            $bad_words[$bad_word] = [
+                $bad_word,
+                str_plural($bad_word),
+                $bad_word[0].str_repeat('*', strlen($bad_word) - 1),
+                $bad_word[0].str_repeat('*', strlen($bad_word) - 2).$bad_word[-1],
+            ];
+        }
+
+        return $bad_words;
+    }
+
+    /**
+     * Get the validation error message.
+     *
+     * @return string
+     */
+    public function message()
+    {
+        return "The word {$this->word} can't appear in the :attribute.";
+    }
+}

config/defaults.php

@@ -1,6 +1,23 @@
 <?php
 
 return [
+    'banned_words' => [
+        /*
+         * The following words are not allowed in show titles, or any other
+         * custom validation field that has a "profanity" flag on it. This list
+         * is adapted from the UK Office of Communications' 2010 study on
+         * acceptable language to use in broadcasting. Presence of any of these
+         * strings, even in longer words, will throw a validation fault.
+         */
+        'partial' => ['shit', 'piss', 'fuck', 'cunt', 'cock', 'tit', 'bitch', 'bastard'],
+
+        /*
+         * These words must be present in isolation to trigger a fault (usually
+         * because there are "safe" words that include these strings, such as
+         * "pass" being a safe word)
+         */
+        'full' => ['ass', 'asshole', 'pussy'],
+    ],
     'directory' => 'https://apps.carleton.edu/stock/ldapimage.php?id=',
     'title' => 'KRLX Community',
     'salt' => env('OAUTH_SALT', 'krlx'),

tests/Feature/CustomRuleTest.php

@@ -2,6 +2,8 @@
 
 namespace Tests\Feature;
 
+use KRLX\Show;
+use KRLX\User;
 use KRLX\Track;
 use Tests\TestCase;
 use Illuminate\Foundation\Testing\RefreshDatabase;
@@ -39,4 +41,50 @@ public function testValidationRuleValidationRule()
             $this->assertEquals(422, $request->status(), "Did not receive HTTP 422 on rule $rule.");
         }
     }
+
+    /**
+     * Test the "Profanity" validation rule: Does a string contain bad words?
+     *
+     * @return void
+     */
+    public function testProfanityRule()
+    {
+        $show = factory(Show::class)->create();
+        $user = factory(User::class)->create();
+        $show->hosts()->attach($user, ['accepted' => true]);
+
+        $partial = config('defaults.banned_words.partial')[0];
+        $full = config('defaults.banned_words.full')[0];
+        $bad_words = [
+            $partial,
+            $partial.'hole',
+            str_plural($partial),
+            $full,
+            str_plural($full),
+            'F***',
+            'F**k',
+            'F@$#',
+        ];
+        $good_words = [
+            'prefix'.$full,
+            'hole',
+            'pals!!!',
+        ];
+        foreach ($good_words as $word) {
+            $request = $this->actingAs($user, 'api')->json('PATCH', "/api/v1/shows/{$show->id}", [
+                'title' => $word,
+            ]);
+            if ($request->status() == 500) {
+                dump($request->json());
+            }
+            $this->assertEquals(200, $request->status(), "Did not receive HTTP 200 with word $word.");
+        }
+        foreach ($bad_words as $word) {
+            $request = $this->actingAs($user, 'api')->json('PATCH', "/api/v1/shows/{$show->id}", [
+                'title' => $word,
+            ]);
+            $this->assertEquals(422, $request->status(), "Did not receive HTTP 422 with word $word.");
+            $this->assertNotEquals('The word  can\'t appear in the title', array_get($request->json(), 'errors.title.0'));
+        }
+    }
 }