Use a DI container to create instances of Validator

The `ValidatorDefaults` is cumbersome, and customising it can be
annoying. Most projects use some sort of dependency injection container,
and by integrating the creation of the `Validator` with the PSR-11, we
allow users to easily customise how they create validators.

Some tasks, like overwriting the `Translator`, become a bit more
verbose, if the user is not already using a PSR-11 container, but I
think that’s a good tradeoff.

Author: henriquemoody

composer.json

@@ -21,6 +21,8 @@
     },
     "require": {
         "php": ">=8.5",
+        "php-di/php-di": "^7.1",
+        "psr/container": "^2.0",
         "respect/stringifier": "^2.0.0",
         "symfony/polyfill-mbstring": "^1.33"
     },

docs/04-message-translation.md

@@ -1,29 +1,26 @@
 # Message translation
 
-You're able to translate message templates with Validation.
+We use dependency injection container to create Validators with all their dependencies. One of these dependencies is the `Translator`, which is responsible for translating validation messages.
 
-```php
-use Respect\Validation\Message\Translator\GettextTranslator;
-use Respect\Validation\ValidatorDefaults;
-
-ValidatorDefaults::setTranslator(new GettextTranslator());
-```
-
-After that, if you call the methods `getMessage()`, `getMessages()`, or `getFullMessage()` from the `ValidationException`, the messages will be translated. The example above will work if you have `gettext` properly configured.
+You can use different translators to translate validation messages into different languages, by overwriting the default container in `ContainerRegistry`, passing the translator you desire.
 
-For non-static usage, pass the translator directly to the `Validator` constructor:
+Luckily, the `ContainerRegistry` has method that creates a pre-configured container using [php-di/php-di](https://php-di.org/). That means you just need to overwrite that service. 
 
 ```php
-use Respect\Validation\Factory;
-use Respect\Validation\Message\StandardFormatter;
+use Respect\Validation\ContainerRegistry;
+use Respect\Validation\Message\Translator;
 use Respect\Validation\Message\Translator\GettextTranslator;
-use Respect\Validation\Validator;
 
-$translator = new GettextTranslator();
+$container = ContainerRegistry::createContainer(); // returns `DI\Container`
+$container->set(Translator::class, new GettextTranslator());
 
-$validator = new Validator(new Factory(), new StandardFormatter(), $translator);
+ContainerRegistry::setContainer($container);
 ```
 
+After that, if you call the methods `getMessage()`, `getMessages()`, or `getFullMessage()` from the `ValidationException`, the messages will be translated. The example above will work if you have `gettext` properly configured.
+
+The `ContainerRegistry` follows the [PSR-11](https://www.php-fig.org/psr/psr-11/) standard, so you can use any container that implements this standard.
+
 ## Supported translators
 
 - `ArrayTranslator`: Translates messages using an array of messages.

library/CloneValidatorFactory.php

@@ -0,0 +1,23 @@
+<?php
+
+/*
+ * Copyright (c) Alexandre Gomes Gaigalas <[email protected]>
+ * SPDX-License-Identifier: MIT
+ */
+
+declare(strict_types=1);
+
+namespace Respect\Validation;
+
+final readonly class CloneValidatorFactory implements ValidatorFactory
+{
+    public function __construct(
+        private Validator $validator,
+    ) {
+    }
+
+    public function create(): Validator
+    {
+        return clone $this->validator;
+    }
+}

library/ContainerRegistry.php

@@ -0,0 +1,78 @@
+<?php
+
+/*
+ * Copyright (c) Alexandre Gomes Gaigalas <[email protected]>
+ * SPDX-License-Identifier: MIT
+ */
+
+declare(strict_types=1);
+
+namespace Respect\Validation;
+
+use DI\Container;
+use Psr\Container\ContainerInterface;
+use Respect\Stringifier\Quoter;
+use Respect\Stringifier\Quoters\StandardQuoter;
+use Respect\Stringifier\Stringifier;
+use Respect\Validation\Message\Formatter\FirstResultStringFormatter;
+use Respect\Validation\Message\Formatter\NestedArrayFormatter;
+use Respect\Validation\Message\Formatter\NestedListStringFormatter;
+use Respect\Validation\Message\Formatter\TemplateResolver;
+use Respect\Validation\Message\InterpolationRenderer;
+use Respect\Validation\Message\Renderer;
+use Respect\Validation\Message\Translator;
+use Respect\Validation\Message\Translator\DummyTranslator;
+use Respect\Validation\Message\ValidationStringifier;
+use Respect\Validation\Transformers\Prefix;
+use Respect\Validation\Transformers\Transformer;
+
+use function DI\autowire;
+use function DI\create;
+use function DI\factory;
+
+final class ContainerRegistry
+{
+    private static ContainerInterface|null $container = null;
+
+    public static function createContainer(): Container
+    {
+        return new Container([
+            Transformer::class => create(Prefix::class),
+            Factory::class => autowire(Factory::class),
+            TemplateResolver::class => create(TemplateResolver::class),
+            Quoter::class => create(StandardQuoter::class)->constructor(ValidationStringifier::MAXIMUM_LENGTH),
+            Stringifier::class => create(ValidationStringifier::class),
+            Translator::class => autowire(DummyTranslator::class),
+            Renderer::class => autowire(InterpolationRenderer::class),
+            ResultFilter::class => create(OnlyFailedChildrenResultFilter::class),
+            'respect.validation.formatter.message' => autowire(FirstResultStringFormatter::class),
+            'respect.validation.formatter.full_message' => autowire(NestedListStringFormatter::class),
+            'respect.validation.formatter.messages' => autowire(NestedArrayFormatter::class),
+            'respect.validation.ignored_backtrace_paths' => [__DIR__ . '/Validator.php'],
+            Validator::class => factory(static fn(Container $container) => new Validator(
+                $container->get(Factory::class),
+                $container->get('respect.validation.formatter.message'),
+                $container->get('respect.validation.formatter.full_message'),
+                $container->get('respect.validation.formatter.messages'),
+                $container->get(Translator::class),
+                $container->get(ResultFilter::class),
+                $container->get('respect.validation.ignored_backtrace_paths'),
+            )),
+            ValidatorFactory::class => autowire(CloneValidatorFactory::class),
+        ]);
+    }
+
+    public static function getContainer(): ContainerInterface
+    {
+        if (!isset(self::$container)) {
+            self::$container = self::createContainer();
+        }
+
+        return self::$container;
+    }
+
+    public static function setContainer(ContainerInterface $instance): void
+    {
+        self::$container = $instance;
+    }
+}

library/Message/ValidationStringifier.php

@@ -38,10 +38,10 @@
 
 final readonly class ValidationStringifier implements Stringifier
 {
+    public const int MAXIMUM_LENGTH = 120;
     private const int MAXIMUM_DEPTH = 3;
     private const int MAXIMUM_NUMBER_OF_ITEMS = 5;
     private const int MAXIMUM_NUMBER_OF_PROPERTIES = self::MAXIMUM_NUMBER_OF_ITEMS;
-    private const int MAXIMUM_LENGTH = 120;
 
     private Stringifier $stringifier;
 

library/Validator.php

@@ -49,15 +49,7 @@ public function __construct(
 
     public static function create(Rule ...$rules): self
     {
-        $validator = new self(
-            ValidatorDefaults::getFactory(),
-            ValidatorDefaults::getMainMessageFormatter(),
-            ValidatorDefaults::getFullMessageFormatter(),
-            ValidatorDefaults::getMessagesFormatter(),
-            ValidatorDefaults::getTranslator(),
-            new OnlyFailedChildrenResultFilter(),
-            ValidatorDefaults::getIgnoredBacktracePaths(),
-        );
+        $validator = ContainerRegistry::getContainer()->get(ValidatorFactory::class)->create();
         $validator->rules = $rules;
 
         return $validator;

library/ValidatorDefaults.php

@@ -0,0 +1,15 @@
+<?php
+
+/*
+ * Copyright (c) Alexandre Gomes Gaigalas <[email protected]>
+ * SPDX-License-Identifier: MIT
+ */
+
+declare(strict_types=1);
+
+namespace Respect\Validation;
+
+interface ValidatorFactory
+{
+    public function create(): Validator;
+}