Extracting the caching logic in Schama to another object

This will become handy when the Database namespaces is extracted into
another repository

src/Database/Connection.php

@@ -21,6 +21,8 @@
 use Cake\Database\Log\LoggingStatement;
 use Cake\Database\Log\QueryLogger;
 use Cake\Database\Query;
+use Cake\Database\Schema\CachedCollection;
+use Cake\Database\Schema\Collection as SchemaCollection;
 use Cake\Database\ValueBinder;
 
 /**
@@ -81,6 +83,13 @@ class Connection {
  */
 	protected $_logger = null;
 
+/**
+ * The schema collection object
+ *
+ * @var \Cake\Database\Schema\Collection
+ */
+	protected $_schemaCollection;
+
 /**
  * Constructor.
  *
@@ -280,12 +289,25 @@ public function newQuery() {
 	}
 
 /**
- * Get a Schema\Collection object for this connection.
+ * Gets or sets a Schema\Collection object for this connection.
  *
+ * @param \Cake\Database\Schema\Collection $collection The schema collection object
  * @return \Cake\Database\Schema\Collection
  */
-	public function schemaCollection() {
-		return new \Cake\Database\Schema\Collection($this);
+	public function schemaCollection(SchemaCollection $collection = null) {
+		if ($collection !== null) {
+			return $this->_schemaCollection = $collection;
+		}
+
+		if ($this->_schemaCollection !== null) {
+			return $this->_schemaCollection;
+		}
+
+		if (!empty($this->_config['cacheMetadata'])) {
+			return $this->_schemaCollection = new CachedCollection($this, $this->_config['cacheMetadata']);
+		}
+
+		return $this->_schemaCollection = new SchemaCollection($this);
 	}
 
 /**
@@ -584,6 +606,7 @@ public function logQueries($enable = null) {
  * @return void
  */
 	public function cacheMetadata($cache) {
+		$this->_schemaCollection = null;
 		$this->_config['cacheMetadata'] = $cache;
 	}
 

src/Database/Schema/Collection.php

@@ -41,14 +41,6 @@ class Collection {
  */
 	protected $_dialect;
 
-/**
- * The name of the cache config key to use for caching table metadata,
- * of false if disabled.
- *
- * @var string|bool
- */
-	protected $_cache = false;
-
 /**
  * Constructor.
  *
@@ -57,11 +49,6 @@ class Collection {
 	public function __construct(Connection $connection) {
 		$this->_connection = $connection;
 		$this->_dialect = $connection->driver()->schemaDialect();
-		$config = $this->_connection->config();
-
-		if (!empty($config['cacheMetadata'])) {
-			$this->cacheMetadata($config['cacheMetadata']);
-		}
 	}
 
 /**
@@ -97,16 +84,6 @@ public function listTables() {
  * @throws \Cake\Database\Exception when table cannot be described.
  */
 	public function describe($name, array $options = []) {
-		$options += ['forceRefresh' => false];
-		$cacheConfig = $this->cacheMetadata();
-		$cacheKey = $this->cacheKey($name);
-
-		if (!empty($cacheConfig) && !$options['forceRefresh']) {
-			$cached = Cache::read($cacheKey, $cacheConfig);
-			if ($cached !== false) {
-				return $cached;
-			}
-		}
 		$config = $this->_connection->config();
 		if (strpos($name, '.')) {
 			list($config['schema'], $name) = explode('.', $name);
@@ -117,13 +94,11 @@ public function describe($name, array $options = []) {
 		if (count($table->columns()) === 0) {
 			throw new Exception(sprintf('Cannot describe %s. It has 0 columns.', $name));
 		}
+
 		$this->_reflect('Index', $name, $config, $table);
 		$this->_reflect('ForeignKey', $name, $config, $table);
 		$this->_reflect('Options', $name, $config, $table);
 
-		if (!empty($cacheConfig)) {
-			Cache::write($cacheKey, $table, $cacheConfig);
-		}
 		return $table;
 	}
 
@@ -156,32 +131,4 @@ protected function _reflect($stage, $name, $config, $table) {
 		$statement->closeCursor();
 	}
 
-/**
- * Get the cache key for a given name.
- *
- * @param string $name The name to get a cache key for.
- * @return string The cache key.
- */
-	public function cacheKey($name) {
-		return $this->_connection->configName() . '_' . $name;
-	}
-
-/**
- * Sets the cache config name to use for caching table metadata, or
- * disabels it if false is passed.
- * If called with no arguments it returns the current configuration name.
- *
- * @param bool $enable whether or not to enable caching
- * @return string|bool
- */
-	public function cacheMetadata($enable = null) {
-		if ($enable === null) {
-			return $this->_cache;
-		}
-		if ($enable === true) {
-			$enable = '_cake_model_';
-		}
-		return $this->_cache = $enable;
-	}
-
 }

tests/TestCase/Database/Schema/CollectionTest.php

@@ -77,7 +77,9 @@ public function testDescribeCache() {
 		$table = $this->connection->schemaCollection()->describe('users');
 
 		Cache::delete('test_users', '_cake_model_');
-		$schema->cacheMetadata(true);
+		$this->connection->cacheMetadata(true);
+		$schema = $this->connection->schemaCollection();
+
 		$result = $schema->describe('users');
 		$this->assertEquals($table, $result);