feature #29 Proposal: Add autoconfiguration for Symfony 4, other tweaks (adiq)

This PR was merged into the 1.4-dev branch.

Discussion
----------

So this is my proposal for SymfonyExtension. Related to #28 

What it changes:

1. Adds autoconfiguration for Symfony 4 (when default `src/Kernel.php` is detected); Improves DX.

So when project bein compliant with new Symfony 4 structure, the configuration will look like:
```
            extensions:
                FriendsOfBehat\SymfonyExtension: ~
```
The standard `.env` file is loaded by default.

2. Explicit settings of `env` and `debug` parameters will override the configuration loaded from `.env` file. This also improves DX, as there is no need for hacky workarounds to get behat working.

3. Fixed issue with the badly named configuration `$config['kernel']['kernel'] = $debugMode;` in 1a39d31f5e

4. Tweaked README to include new configuration details


When it might seem only like an improvement, it's required to get behat working on new Symfony 4 structure when you: do not want to store a separate copy of `.env` with only `APP_ENV` changed to `test`, do not want to change those settings back and forth in `.env` file; which I consider not good practice and not good DX for sure 😄 

Commits
-------

09c6530115 Add autoconfiguration for Symfony 4, allow overriding .env setting by using explicit env and debug settings, tweaks
141074a24e Tweak README to include new configuration details for Symfony 4, tweak variable name
149d41087f Add symfony 4 configuration loading when bootstrap is null; tweaked formatting, naming, tests and readme
49c4fc2a0e Tweak README typos
99db863175 Tweaks after CR: remove obsolete docblocks, fix code formatting to match ECS

README.md

@@ -28,30 +28,53 @@ ensures that application behaviour will not be affected by stateful services.
             FriendsOfBehat\SymfonyExtension: ~
     ```
 
-    **Symfony 3 configuration**
+3. Good luck & have fun!
 
-    ```
+    
-    FriendsOfBehat\SymfonyExtension:
+## Configuration
+
+SymfonyExtension provides kind of autoconfiguration feature.
+When none explicit configuration is set, we will set for you sane default that will get you running fast.
+
+**Default Symfony 3 configuration**
+
+```
+FriendsOfBehat\SymfonyExtension:
     kernel:
-            bootstrap: 'var/bootstrap.php.cache'
+        bootstrap: 'app/autoload.php' # you may want to use var/bootstrap.php.cache instead
         path: app/AppKernel.php
         class: 'AppKernel'
         env: test
         debug: true
-    ```
+```
 
-    **Symfony 4 configuration**
+**Default Symfony 4 configuration**
 
-    ```
+```
-    FriendsOfBehat\SymfonyExtension:
+FriendsOfBehat\SymfonyExtension:
     # .env.dist file will be used if .env file does not exist
     env_file: .env
     kernel:
-            class: 'MyTrip\Kernel'
+        bootstrap: ~
         path: src/Kernel.php
-            debug: true
+        class: 'App\Kernel'
-    ```
+        env: test # When explicitly set, will override APP_ENV loaded from env_file file
+        debug: true  # When explicitly set, will override APP_DEBUG loaded from env_file file
+```
 
-    Symfony 4 does not have bootstrap file anymore and the environment is configured in the .env file.
+Symfony 4 is automatically detected, based on the existence of default `src/Kernel.php` kernel file.
 
-3. Good luck & have fun!
+If you did not migrate to new Symfony structure yet or you are using custom paths/naming; you need to configure `kernel.bootstrap` parameter, to enable default Symfony 4 configuration as shown in the example below:
+
+```
+FriendsOfBehat\SymfonyExtension:
+    # env_file: .env # loaded from the default configuration
+    kernel:
+        bootstrap: ~ # this enables default Symfony 4 configuration
+        path: app/AppKernel.php
+        # class: 'App\Kernel' # loaded from the default configuration
+        # env: test # loaded from the default configuration
+        # debug: true  # loaded from the default configuration
+```
+
+Of course, you can always change each of those settings.

features/not_crashing_behat.feature

@@ -3,14 +3,17 @@ Feature: Not crashing Behat
     As a Behat User
     I want to have Behat up and running after enabling this extension
 
-    Scenario: Not crashing Behat
+    Scenario: Successful boot the Symfony kernel with autoconfiguration
         Given a Behat configuration containing:
         """
         default:
             extensions:
-                FriendsOfBehat\SymfonyExtension:
+                FriendsOfBehat\SymfonyExtension: ~
-                    kernel:
+        """
-                        bootstrap: ~
+        And a file "app/autoload.php" containing:
+        """
+        <?php
+
         """
         And a file "app/AppKernel.php" containing:
         """
@@ -29,25 +32,32 @@ Feature: Not crashing Behat
         When I run Behat
         Then it should pass
 
-    Scenario: Not crashing Behat with CrossContainerExtension
+    Scenario: Successful boot the Symfony kernel with explicit configuration
         Given a Behat configuration containing:
         """
         default:
             extensions:
                 FriendsOfBehat\SymfonyExtension:
                     kernel:
-                        bootstrap: ~
+                        bootstrap: app/autoload.php
-
+                        path: app/MyKernel.php
-                FriendsOfBehat\CrossContainerExtension: ~
+                        class: MyKernel
+                        env: test
+                        debug: true
         """
-        And a file "app/AppKernel.php" containing:
+        And a file "app/autoload.php" containing:
+        """
+        <?php
+
+        """
+        And a file "app/MyKernel.php" containing:
         """
         <?php
 
         use Symfony\Component\HttpKernel\Kernel;
         use Symfony\Component\Config\Loader\LoaderInterface;
 
-        class AppKernel extends Kernel
+        class MyKernel extends Kernel
         {
             public function registerBundles() { return []; }
             public function registerContainerConfiguration(LoaderInterface $loader) {}
@@ -57,7 +67,38 @@ Feature: Not crashing Behat
         When I run Behat
         Then it should pass
 
-    Scenario: This extension boot a Symfony4 kernel
+
+    Scenario: Successful boot the Symfony 4 kernel with autoconfiguration
+        Given a Behat configuration containing:
+        """
+        default:
+            extensions:
+                FriendsOfBehat\SymfonyExtension: ~
+        """
+        And a file ".env" containing:
+        """
+        APP_ENV=dev
+        """
+        And a file "src/Kernel.php" containing:
+        """
+        <?php
+
+        namespace App;
+
+        use Symfony\Component\HttpKernel\Kernel as BaseKernel;
+        use Symfony\Component\Config\Loader\LoaderInterface;
+
+        class Kernel extends BaseKernel
+        {
+            public function registerBundles() { return []; }
+            public function registerContainerConfiguration(LoaderInterface $loader) {}
+        }
+        """
+        And a feature file with passing scenario
+        When I run Behat
+        Then it should pass
+
+    Scenario: Successful boot the Symfony 4 kernel with explicit configuration
         Given a Behat configuration containing:
         """
         default:
@@ -98,9 +139,11 @@ Feature: Not crashing Behat
                 FriendsOfBehat\SymfonyExtension:
                     env_file: .env_in_memory
                     kernel:
+                        bootstrap: ~
                         path: src/MyKernel.php
                         class: MyKernel
-                        bootstrap: ~
+                        env: dev
+                        debug: true
         """
         And a file ".env_in_memory.dist" containing:
         """
@@ -122,3 +165,33 @@ Feature: Not crashing Behat
         And a feature file with passing scenario
         When I run Behat
         Then it should pass
+
+    Scenario: Not crashing Behat with CrossContainerExtension
+        Given a Behat configuration containing:
+        """
+        default:
+            extensions:
+                FriendsOfBehat\SymfonyExtension: ~
+                FriendsOfBehat\CrossContainerExtension: ~
+        """
+        And a file "app/autoload.php" containing:
+        """
+        <?php
+
+        """
+        And a file "app/AppKernel.php" containing:
+        """
+        <?php
+
+        use Symfony\Component\HttpKernel\Kernel;
+        use Symfony\Component\Config\Loader\LoaderInterface;
+
+        class AppKernel extends Kernel
+        {
+            public function registerBundles() { return []; }
+            public function registerContainerConfiguration(LoaderInterface $loader) {}
+        }
+        """
+        And a feature file with passing scenario
+        When I run Behat
+        Then it should pass

src/ServiceContainer/SymfonyExtension.php

@@ -61,7 +61,35 @@ final class SymfonyExtension implements Extension
     /**
      * Enable or disable the debug mode
      */
-    private const DEBUG_MODE = false;
+    private const DEFAULT_DEBUG_MODE = true;
+
+    /**
+     * Default Symfony configuration
+     */
+    private const SYMFONY_DEFAULTS = [
+        'env_file' => null,
+        'kernel' => [
+            'bootstrap' => 'app/autoload.php',
+            'path' => 'app/AppKernel.php',
+            'class' => 'AppKernel',
+            'env' => self::DEFAULT_ENV,
+            'debug' => self::DEFAULT_DEBUG_MODE,
+        ],
+    ];
+
+    /**
+     * Default Symfony 4 configuration
+     */
+    private const SYMFONY_4_DEFAULTS = [
+        'env_file' => '.env',
+        'kernel' => [
+            'bootstrap' => null,
+            'path' => 'src/Kernel.php',
+            'class' => 'App\Kernel',
+            'env' => self::DEFAULT_ENV,
+            'debug' => self::DEFAULT_DEBUG_MODE,
+        ],
+    ];
 
     /**
      * @var CrossContainerProcessor|null
@@ -91,18 +119,16 @@ final class SymfonyExtension implements Extension
     public function configure(ArrayNodeDefinition $builder): void
     {
         $builder
-            ->addDefaultsIfNotSet()
             ->children()
-                    ->scalarNode('env_file')->defaultNull()->end()
+                ->scalarNode('env_file')->end()
                 ->arrayNode('kernel')
                     ->addDefaultsIfNotSet()
                     ->children()
-                            ->scalarNode('bootstrap')->defaultValue('app/autoload.php')->end()
+                        ->scalarNode('bootstrap')->defaultFalse()->end()
-                            ->scalarNode('path')->defaultValue('app/AppKernel.php')->end()
+                        ->scalarNode('path')->end()
-                            ->scalarNode('class')->defaultValue('AppKernel')->end()
+                        ->scalarNode('class')->end()
-                            ->scalarNode('env')->defaultValue('test')->end()
+                        ->scalarNode('env')->end()
-                            ->booleanNode('debug')->defaultTrue()->end()
+                        ->booleanNode('debug')->end()
-                        ->end()
                     ->end()
                 ->end()
             ->end()
@@ -114,17 +140,7 @@ final class SymfonyExtension implements Extension
      */
     public function load(ContainerBuilder $container, array $config): void
     {
-        if (null !== $config['env_file']) {
+        $config = $this->autoconfigure($container, $config);
-            $envFilePath = sprintf('%s/%s', $container->getParameter('paths.base'), $config['env_file']);
-            $envFilePath = file_exists($envFilePath) ? $envFilePath : $envFilePath.'.dist';
-            (new Dotenv())->load($envFilePath);
-
-            $environment = false !== getenv('APP_ENV') ? getenv('APP_ENV') : self::DEFAULT_ENV;
-            $debugMode = false !== getenv('APP_DEBUG') ? getenv('APP_DEBUG') : self::DEBUG_MODE;
-
-            $config['kernel']['env'] = $environment;
-            $config['kernel']['kernel'] = $debugMode;
-        }
 
         $this->loadKernel($container, $config['kernel']);
         $this->loadKernelContainer($container);
@@ -145,9 +161,41 @@ final class SymfonyExtension implements Extension
     {
     }
 
-    /**
+    private function autoconfigure(ContainerBuilder $container, array $userConfig): array
-     * @param ContainerBuilder $container
+    {
-     */
+        $defaults = self::SYMFONY_DEFAULTS;
+
+        $symfonyFourKernelPath = sprintf('%s/%s', $container->getParameter('paths.base'), self::SYMFONY_4_DEFAULTS['kernel']['path']);
+        if ($userConfig['kernel']['bootstrap'] === null || file_exists($symfonyFourKernelPath)) {
+            $defaults = self::SYMFONY_4_DEFAULTS;
+        }
+
+        $userConfig['kernel']['bootstrap'] = $userConfig['kernel']['bootstrap'] === false ? null : $userConfig['kernel']['bootstrap'];
+
+        $config = array_replace_recursive($defaults, $userConfig);
+
+        if (null !== $config['env_file']) {
+            $this->loadEnvVars($container, $config['env_file']);
+
+            if (!isset($userConfig['kernel']['env']) && false !== getenv('APP_ENV')) {
+                $config['kernel']['env'] = getenv('APP_ENV');
+            }
+
+            if (!isset($userConfig['kernel']['debug']) && false !== getenv('APP_DEBUG')) {
+                $config['kernel']['debug'] = getenv('APP_DEBUG');
+            }
+        }
+
+        return $config;
+    }
+
+    private function loadEnvVars(ContainerBuilder $container, string $fileName): void
+    {
+        $envFilePath = sprintf('%s/%s', $container->getParameter('paths.base'), $fileName);
+        $envFilePath = file_exists($envFilePath) ? $envFilePath : $envFilePath . '.dist';
+        (new Dotenv())->load($envFilePath);
+    }
+
     private function loadKernel(ContainerBuilder $container, array $config): void
     {
         $definition = new Definition($config['class'], [
@@ -167,9 +215,6 @@ final class SymfonyExtension implements Extension
         $this->requireKernelBootstrapFile($container->getParameter('paths.base'), $config['bootstrap']);
     }
 
-    /**
-     * @param ContainerBuilder $container
-     */
     private function loadKernelContainer(ContainerBuilder $container): void
     {
         $containerDefinition = new Definition(Container::class);
@@ -181,25 +226,16 @@ final class SymfonyExtension implements Extension
         $container->setDefinition(self::KERNEL_CONTAINER_ID, $containerDefinition);
     }
 
-    /**
-     * @param ContainerBuilder $container
-     */
     private function loadDriverKernel(ContainerBuilder $container): void
     {
         $container->setDefinition(self::DRIVER_KERNEL_ID, $container->findDefinition(self::KERNEL_ID));
     }
 
-    /**
-     * @param ContainerBuilder $container
-     */
     private function loadSharedKernel(ContainerBuilder $container): void
     {
         $container->setDefinition(self::SHARED_KERNEL_ID, $container->findDefinition(self::KERNEL_ID));
     }
 
-    /**
-     * @param ContainerBuilder $container
-     */
     private function loadSharedKernelContainer(ContainerBuilder $container): void
     {
         $containerDefinition = new Definition(Container::class);
@@ -212,8 +248,6 @@ final class SymfonyExtension implements Extension
     }
 
     /**
-     * @param ContainerBuilder $container
-     *
      * @throws \Exception
      */
     private function loadKernelRebooter(ContainerBuilder $container): void
@@ -225,8 +259,6 @@ final class SymfonyExtension implements Extension
     }
 
     /**
-     * @param ContainerBuilder $container
-     *
      * @throws \Exception
      */
     private function declareSymfonyContainers(ContainerBuilder $container): void
@@ -257,9 +289,6 @@ final class SymfonyExtension implements Extension
         }
     }
 
-    /**
-     * @param ExtensionManager $extensionManager
-     */
     private function initializeCrossContainerProcessor(ExtensionManager $extensionManager): void
     {
         /** @var CrossContainerExtension $extension */
@@ -269,9 +298,6 @@ final class SymfonyExtension implements Extension
         }
     }
 
-    /**
-     * @param ExtensionManager $extensionManager
-     */
     private function registerSymfonyDriverFactory(ExtensionManager $extensionManager): void
     {
         /** @var MinkExtension|null $minkExtension */
@@ -286,12 +312,6 @@ final class SymfonyExtension implements Extension
         ));
     }
 
-    /**
-     * @param string $basePath
-     * @param string $kernelPath
-     *
-     * @return string|null
-     */
     private function getKernelFile(string $basePath, string $kernelPath): ?string
     {
         $possibleFiles = [
@@ -309,9 +329,6 @@ final class SymfonyExtension implements Extension
     }
 
     /**
-     * @param string $basePath
-     * @param string|null $bootstrapPath
-     *
      * @throws \DomainException
      */
     private function requireKernelBootstrapFile(string $basePath, ?string $bootstrapPath): void