refs #7983 let plugins add or remove fields to websites and better settings api

1 files changed, 117 insertions, 0 deletions

diff --git a/core/Settings/Storage/Storage.php b/core/Settings/Storage/Storage.php
new file mode 100644
index 0000000000..b24282068d
--- /dev/null
+++ b/core/Settings/Storage/Storage.php
@@ -0,0 +1,117 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+
+namespace Piwik\Settings\Storage;
+
+use Piwik\Settings\Storage\Backend;
+
+/**
+ * A storage stores values for multiple settings. Storing multiple settings here saves having to do
+ * a "get" for each individual setting. A storage is usually stared between all individual setting instances
+ * within a plugin.
+ */
+class Storage
+{
+    /**
+     * Array containing all plugin settings values: Array( [setting-key] => [setting-value] ).
+     *
+     * @var array
+     */
+    protected $settingsValues = array();
+
+    // for lazy loading of setting values
+    private $settingValuesLoaded = false;
+
+    /**
+     * @var Backend\BackendInterface
+     */
+    private $backend;
+
+    /**
+     * Defines whether a value has changed since the settings were loaded or not.
+     * @var bool
+     */
+    private $isDirty = false;
+
+    public function __construct(Backend\BackendInterface $backend)
+    {
+        $this->backend = $backend;
+    }
+
+    /**
+     * Get the currently used backend for this storage.
+     * @return Backend\BackendInterface
+     */
+    public function getBackend()
+    {
+        return $this->backend;
+    }
+
+    /**
+     * Saves (persists) the current setting values in the database if a value has actually changed.
+     */
+    public function save()
+    {
+        if ($this->isDirty) {
+            $this->backend->save($this->settingsValues);
+
+            $this->isDirty = false;
+
+            Backend\Cache::clearCache();
+        }
+    }
+
+    /**
+     * Returns the current value for a setting. If no value is stored, the default value
+     * is be returned.
+     *
+     * @param string $key  The name / key of a setting
+     * @param mixed $defaultValue Default value that will be used in case no value for this setting exists yet
+     * @param string $type The PHP internal type the value of the setting should have, see FieldConfig::TYPE_*
+     *                     constants. Only an actual value of the setting will be converted to the given type, the
+     *                     default value will not be converted.
+     * @return mixed
+     */
+    public function getValue($key, $defaultValue, $type)
+    {
+        $this->loadSettingsIfNotDoneYet();
+
+        if (array_key_exists($key, $this->settingsValues)) {
+            settype($this->settingsValues[$key], $type);
+            return $this->settingsValues[$key];
+        }
+
+        return $defaultValue;
+    }
+
+    /**
+     * Sets (overwrites) the value of a setting in memory. To persist the change across requests, {@link save()} must be
+     * called.
+     *
+     * @param string $key  The name / key of a setting
+     * @param mixed $value The value that shall be set for the given setting.
+     */
+    public function setValue($key, $value)
+    {
+        $this->loadSettingsIfNotDoneYet();
+
+        $this->isDirty = true;
+        $this->settingsValues[$key] = $value;
+    }
+
+    private function loadSettingsIfNotDoneYet()
+    {
+        if ($this->settingValuesLoaded) {
+            return;
+        }
+
+        $this->settingValuesLoaded = true;
+        $this->settingsValues = $this->backend->load();
+    }
+}