Adding an interface to define the necessary public methods.

Adding insertion of configure readers.
Adding tests.

cake/libs/config/php_reader.php

@@ -24,7 +24,7 @@
  *
  * @package cake.libs.config
  */
-class PhpReader {
+class PhpReader implements ConfigReaderInterface {
 /**
  * The path this reader finds files on.
  *

cake/libs/configure.php

@@ -40,6 +40,14 @@ class Configure {
 		'debug' => 0
 	);
 
+/**
+ * Configured reader classes, used to load config files from resources
+ *
+ * @var array
+ * @see Configure::load()
+ */
+	protected static $_readers = array();
+
 /**
  * Initializes configure and runs the bootstrap process.
  * Bootstrapping includes the following steps:
@@ -249,6 +257,33 @@ public static function delete($var = null) {
 		self::$_values[$names[0]] = Set::remove(self::$_values[$names[0]], $names[1]);
 	}
 
+/**
+ * Add a new reader to Configure.  Readers allow you to read configuration 
+ * files in various formats/storage locations.  CakePHP comes with two built-in readers
+ * PhpReader and IniReader.  You can also implement your own reader classes in your application.
+ *
+ * To add a new reader to Configure:
+ *
+ * `Configure::reader('ini', new IniReader());`
+ *
+ * @param string $alias The name of the reader being configured.  This alias is used later to 
+ *   read values from a specific reader.
+ * @param ConfigReaderInterface $reader The reader to append.
+ * @return void
+ */
+	public static function reader($alias, ConfigReaderInterface $reader) {
+		self::$_readers[$alias] = $reader;
+	}
+
+/**
+ * Gets the names of the configured reader objects.
+ *
+ * @return array Array of the configured reader objects.
+ */
+	public static function configured() {
+		return array_keys(self::$_readers);
+	}
+
 /**
  * Loads a file from app/config/configure_file.php.
  *
@@ -380,4 +415,21 @@ private static function __writeConfig($content, $name, $write = true) {
 		}
 	}
 
+}
+
+/**
+ * An interface for creating objects compatible with Configure::load()
+ *
+ * @package cake.libs
+ */
+interface ConfigReaderInterface {
+/**
+ * Read method is used for reading configuration information from sources.
+ * These sources can either be static resources like files, or dynamic ones like
+ * a database, or other datasource.
+ *
+ * @param string $key 
+ * @return array An array of data to merge into the runtime configuration
+ */
+	function read($key);
 }

cake/tests/cases/libs/configure.test.php

@@ -19,6 +19,7 @@
  * @since         CakePHP(tm) v 1.2.0.5432
  * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
  */
+App::import('Core', 'config/PhpReader');
 
 /**
  * ConfigureTest
@@ -256,5 +257,29 @@ function testVersion() {
 		$result = Configure::version();
 		$this->assertTrue(version_compare($result, '1.2', '>='));
 	}
+
+/**
+ * test adding new readers.
+ *
+ * @return void
+ */
+	function testReaderSetup() {
+		$reader = new PhpReader();
+		Configure::reader('test', $reader);
+		$configured = Configure::configured();
+
+		$this->assertTrue(in_array('test', $configured));
+	}
+
+/**
+ * test reader() throwing exceptions on missing interface.
+ *
+ * @expectedException Exception
+ * @return void
+ */
+	function testReaderExceptionOnIncorrectClass() {
+		$reader = new StdClass();
+		Configure::reader('test', $reader);
+	}
 }