Added getSubConfig() functionality.

CHANGELOG.md

@@ -2,6 +2,11 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 
+## [0.1.13] - 2016-02-17
+### Added
+- Added `getSubConfig()` to extract the subtree at a specific level & key.
+- Added corresponding tests.
+
 ## [0.1.12] - 2016-02-17
 ### Fixed
 - Updated `brightnucleus/exceptions` dependency.
@@ -76,6 +81,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ### Added
 - Initial release to GitHub.
 
+[0.1.13]: https://github.com/brightnucleus/config/compare/v0.1.12...v0.1.13
 [0.1.12]: https://github.com/brightnucleus/config/compare/v0.1.11...v0.1.12
 [0.1.11]: https://github.com/brightnucleus/config/compare/v0.1.10...v0.1.11
 [0.1.10]: https://github.com/brightnucleus/config/compare/v0.1.9...v0.1.10

README.md

@@ -64,24 +64,20 @@ class Example {
 	/**
 	 * Instantiate an Example object.
 	 *
-	 * @param ConfigInterface $config     Config to parametrize the object.
-	 * @param string|null     $config_key Optional. Config key that represents the
- 	 *                                    subtree for this class.
-	 * @throws RuntimeException           If the Config could not be parsed correctly.
+	 * @param ConfigInterface $config Config to parametrize the object.
+	 * @throws RuntimeException       If the Config could not be parsed correctly.
 	 */
-	public function __construct( ConfigInterface $config, $config_key = null ) {
-		$this->processConfig( $config, $config_key ?: 'BrightNucleus\Example' );
+	public function __construct( ConfigInterface $config ) {
+		$this->processConfig( $config );
 	}
 
 	/**
 	 * Do something.
 	 */
 	public function run() {
-		$key = 'test_key;';
+		$key = 'test_key';
 
-		// Outputs:
-		// The value of the config key "test_key" is "test_value".
-		printf(
+		return sprintf(
 		_( 'The value of the config key "$1%s" is "$2%s".'),
 			$key,
 			$this->getConfigKey( $key )
@@ -90,6 +86,26 @@ class Example {
 }
 ```
 
+### Example of how to put the configuration into the class
+
+You can combine all of your configurations into 1 single file and only pass "Sub-Configurations" to the individual components. This way, you can save a file access and a complete validation pass for each component.
+
+Here's how you can pass the configuration file into the class:
+
+```PHP
+<?php namespace BrightNucleus\Example;
+
+function init() {
+	$configFile = __DIR__ . '/config/example_settings.php';
+	$config     = new Config( include( $configFile ) );
+	$example    = new Example( $config->getSubConfig( 'BrightNucleus\Example' ) );
+
+	// Outputs:
+	// The value of the config key "test_key" is "test_value".
+	echo $example->run();
+}
+```
+
 See [link to post coming soon] for more details.
 
 ## Contributing

src/AbstractConfig.php

@@ -72,17 +72,7 @@ public function __construct(array $config, $delimiter = null)
      */
     public function getKey()
     {
-        $keys = $this->getKeyArguments(func_get_args());
-        Assert\that($keys)->all()->string()->notEmpty();
-
-        if (! $this->hasKey($keys)) {
-            throw new OutOfRangeException(
-                sprintf(
-                    _('The configuration key %1$s does not exist.'),
-                    implode('->', $keys)
-                )
-            );
-        }
+        $keys = $this->validateKeys(func_get_args());
 
         $keys  = array_reverse($keys);
         $array = $this->getArrayCopy();
@@ -109,7 +99,6 @@ public function hasKey()
     {
         try {
             $keys = array_reverse($this->getKeyArguments(func_get_args()));
-            Assert\thatAll($keys)->string()->notEmpty();
 
             $array = $this->getArrayCopy();
             while (count($keys) > 0) {
@@ -149,6 +138,66 @@ public function getKeys()
         return array_keys((array)$this);
     }
 
+    /**
+     * Get a new config at a specific sub-level.
+     *
+     * @since 0.1.13
+     *
+     * @param string ... List of keys.
+     * @return ConfigInterface
+     * @throws BadMethodCallException If no argument was provided.
+     * @throws OutOfRangeException If an unknown key is requested.
+     */
+    public function getSubConfig()
+    {
+        $keys = $this->validateKeys(func_get_args());
+
+        $subConfig = clone $this;
+        $subConfig->reduceToSubKey($keys);
+
+        return $subConfig;
+    }
+
+    /**
+     * Validate a set of keys to make sure they exist.
+     *
+     * @since 0.1.13
+     *
+     * @param string ... List of keys.
+     * @return array List of keys.
+     * @throws BadMethodCallException If no argument was provided.
+     * @throws OutOfRangeException If an unknown key is requested.
+     */
+    public function validateKeys()
+    {
+        $keys = $this->getKeyArguments(func_get_args());
+
+        Assert\that($keys)->all()->string()->notEmpty();
+
+        if (! $this->hasKey($keys)) {
+            throw new OutOfRangeException(
+                sprintf(
+                    _('The configuration key %1$s does not exist.'),
+                    implode('->', $keys)
+                )
+            );
+        }
+
+        return $keys;
+    }
+
+    /**
+     * Reduce the currently stored config array to a subarray at a specific level.
+     *
+     * @since 0.1.13
+     *
+     * @param array $keys Array of keys that point to a key down in the hierarchy.
+     */
+    protected function reduceToSubkey(array $keys)
+    {
+        $this->exchangeArray($this->getKey($keys));
+    }
+
     /**
      * Recursively extract the configuration key arguments from an arbitrary array.
      *

src/ConfigInterface.php

@@ -62,7 +62,6 @@ public function hasKey();
      * @since 0.1.4 Accepts list of keys.
      *
      * @param string ... List of keys.
-     *
      * @return mixed
      */
     public function getKey();
@@ -93,4 +92,14 @@ public function getKeys();
      * @return boolean
      */
     public function isValid();
+
+    /**
+     * Get a new config at a specific sub-level.
+     *
+     * @since 0.1.13
+     *
+     * @param string ... List of keys.
+     * @return ConfigInterface
+     */
+    public function getSubConfig();
 }

src/ConfigTrait.php

@@ -42,8 +42,7 @@ protected function processConfig(ConfigInterface $config)
             try {
                 $keys = func_get_args();
                 array_shift($keys);
-                Assert\that($keys)->all()->string()->notEmpty();
-                $config = new Config($config->getKey($keys));
+                $config = $config->getSubConfig($keys);
             } catch (Exception $exception) {
                 throw new RuntimeException(
                     sprintf(

tests/ConfigTest.php

@@ -30,7 +30,7 @@ class ConfigTest extends \PHPUnit_Framework_TestCase
      * Don't use an array const to avoid bumping PHP requirement to 5.6.
      */
     protected static $test_array = [
-        'random_string' => 'test_value',
+        'random_string'    => 'test_value',
         'positive_integer' => 42,
         'negative_integer' => -256,
         'positive_boolean' => true,
@@ -354,4 +354,37 @@ public function testConfigFileWithDefaults()
         );
         $this->assertFalse($config->getKey('some_other_key'));
     }
+
+    public function testGetSubConfig()
+    {
+        $config      = new Config(__DIR__ . '/fixtures/deep_config_file.php');
+        $subconfig   = $config->getSubConfig('vendor/package');
+        $subsection1 = $config->getSubConfig('vendor', 'package', 'section_1');
+        $subsection2 = $subconfig->getSubConfig('section_2');
+        $this->assertInstanceOf('\BrightNucleus\Config\ConfigInterface', $config);
+        $this->assertInstanceOf('\BrightNucleus\Config\AbstractConfig', $config);
+        $this->assertInstanceOf('\BrightNucleus\Config\Config', $config);
+        $this->assertInstanceOf('\BrightNucleus\Config\ConfigInterface', $subconfig);
+        $this->assertInstanceOf('\BrightNucleus\Config\AbstractConfig', $subconfig);
+        $this->assertInstanceOf('\BrightNucleus\Config\Config', $subconfig);
+        $this->assertInstanceOf('\BrightNucleus\Config\ConfigInterface', $subsection1);
+        $this->assertInstanceOf('\BrightNucleus\Config\AbstractConfig', $subsection1);
+        $this->assertInstanceOf('\BrightNucleus\Config\Config', $subsection1);
+        $this->assertInstanceOf('\BrightNucleus\Config\ConfigInterface', $subsection2);
+        $this->assertInstanceOf('\BrightNucleus\Config\AbstractConfig', $subsection2);
+        $this->assertInstanceOf('\BrightNucleus\Config\Config', $subsection2);
+        $this->assertTrue($config->hasKey('vendor/package'));
+        $this->assertTrue($config->hasKey('vendor/package/section_1/test_key_1'));
+        $this->assertTrue($config->hasKey('vendor/package/section_2/test_key_2'));
+        $this->assertTrue($subconfig->hasKey('section_1/test_key_1'));
+        $this->assertTrue($subconfig->hasKey('section_2/test_key_2'));
+        $this->assertTrue($subsection1->hasKey('test_key_1'));
+        $this->assertTrue($subsection2->hasKey('test_key_2'));
+        $this->setExpectedException(
+            'BrightNucleus\Exception\OutOfRangeException',
+            'The configuration key some_other_key does not exist.'
+        );
+        $this->assertFalse($config->getSubConfig('some_other_key'));
+
+    }
 }

tests/fixtures/deep_config_file.php

@@ -0,0 +1,23 @@
+<?php
+/**
+ * Config file with deeply nested test data for the unit tests.
+ *
+ * @package   BrightNucleus\Config
+ * @author    Alain Schlesser <alain.schlesser@gmail.com>
+ * @license   GPL-2.0+
+ * @link      http://www.brightnucleus.com/
+ * @copyright 2016 Alain Schlesser, Bright Nucleus
+ */
+
+namespace BrightNucleus\Config;
+
+$test_data = [
+    'section_1' => [
+        'test_key_1' => 'test_value_1',
+    ],
+    'section_2' => [
+        'test_key_2' => 'test_value_2',
+    ],
+];
+
+return ['vendor' => ['package' => $test_data]];