Initial release

.editorconfig

@@ -0,0 +1,17 @@
+# For more information about the properties used in this file,
+# please see the EditorConfig documentation:
+# http://editorconfig.org
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_size = 4
+indent_style = tab
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[{*.yml,package.json}]
+indent_size = 2
+
+# The indent size used in the package.json file cannot be changed:
+# https://github.com/npm/npm/pull/3180#issuecomment-16336516

.htaccess

@@ -0,0 +1,3 @@
+<FilesMatch "\.(php|php3|php4|php5|phtml|inc)$">
+	Deny from all
+</FilesMatch>

README.md

@@ -1,2 +1,34 @@
-# silverstripe-persistent-dataobject
-Persistent, immutable and optionally versioned DataObjects for SilverStripe 4
+# Persistent DataObjects - Experimental / Work in Progress
+
+Persistent and optionally immutable & versioned DataObjects for SilverStripe
+
+The two major features of this module are:
+
+1. **A DataObject subclass that can not be deleted**    
+   Calling `->delete()` will mark an object as deleted, but not actually delete it    
+   *(Where necessary, objects can still be deleted by calling `->purge()`)*
+1. **A DataObjectExtension that adds versioning**    
+   In contrast to the "silverstripe-versioned" module, versioning is achived by 
+   making DataObjects immutable and overloading `->write()` to create a duplicate 
+   of the current record instead of saving the existing.        
+   This means the `ID` becomes the unique version number, while an additional 
+   `VersionGroupID` and `VersionGroupLatest` keep track of the relation of records. 
+   The benefit of this approach is being able to easily reference a version of an
+   entry rather than always the latest version. Thus making it possible to have 
+   persistent storage of information that is easily integrable in other parts of 
+   SilverStripe (eg an invoice can safely reference a product price and does not 
+   need to create a snapshot).
+
+## TODOs / Planed features
+
+- [ ] Tests
+- [ ] Revisit decision to put VersionGroup_ID on DataObject rather than subclasses
+- [ ] Extend GridField integration
+   - [ ] Hide/Show deleted records button
+   - [ ] History view to access older version from within a DataObject
+- [ ] Implement non GridField form fields (eg Relation Dropdown that let's the user pick a entry and a version)
+- [ ] Implement Database Field/Relation that references VersionGroupID instead of ID?
+- [ ] Documentation
+   - [ ] Explain the usecase in more detail
+   - [ ] Examples
+- [ ] SilverStripe 4 Support

composer.json

@@ -15,6 +15,6 @@
 		"issues": "https://github.com/Zauberfisch/silverstripe-persistent-dataobject/issues"
 	},
 	"require": {
-		"silverstripe/framework": "^3"
+		"silverstripe/framework": "^3.6"
 	}
 }

src/Admin/ModelAdmin.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace zauberfisch\PersistentDataObject\Admin;
+
+use zauberfisch\PersistentDataObject\Form\GridField\Config_RecordEditor;
+use zauberfisch\PersistentDataObject\Form\GridField\DetailForm;
+
+/**
+ * @author zauberfisch
+ */
+class ModelAdmin extends \ModelAdmin {
+	public function getEditForm($id = null, $fields = null) {
+		/** @var \Form $return */
+		$return = parent::getEditForm($id, $fields);
+		/** @var \GridField $grid */
+		$grid = $return->Fields()->fieldByName($this->sanitiseClassName($this->modelClass));
+		$config = new Config_RecordEditor();
+		$config->removeComponentsByType(\GridFieldFilterHeader::class);
+		// Validation
+		if (singleton($this->modelClass)->hasMethod('getCMSValidator')) {
+			$detailValidator = singleton($this->modelClass)->getCMSValidator();
+			/** @var DetailForm $detailForm */
+			$detailForm = $config->getComponentByType(DetailForm::class);
+			$detailForm->setValidator($detailValidator);
+		}
+		// Import / Export
+		$config->addComponent((new \GridFieldExportButton('buttons-before-left'))->setExportColumns($this->getExportFields()));
+		//if ($this->showImportForm) {
+		//	$config->addComponent(
+		//		GridFieldImportButton::create('buttons-before-left')
+		//			->setImportForm($this->ImportForm())
+		//			->setModalTitle(_t('ModelAdmin.IMPORT', 'Import from CSV'))
+		//	);
+		//}
+		$grid->setConfig($config);
+		return $return;
+	}
+}
+

src/Form/GridField/Action/EditButton.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace zauberfisch\PersistentDataObject\Form\GridField\Action;
+
+use zauberfisch\PersistentDataObject\Model\VersionedDataObjectExtension;
+
+class EditButton extends \GridFieldEditButton {
+	public function getColumnContent($gridField, $record, $columnName) {
+		if ($record->hasExtension(VersionedDataObjectExtension::class)) {
+			/** @var \PersistentDataObject_Model_DataObject|VersionedDataObjectExtension $record */
+			$data = new \ArrayData([
+				'Link' => \Controller::join_links(
+					$gridField->Link('version-group'),
+					$record->VersionGroupID,
+					'item',
+					$record->isLatestVersion(true) ? 'latest' : $record->ID,
+					'edit'
+				),
+			]);
+			$template = \SSViewer::get_templates_by_class(\GridFieldEditButton::class, '', \GridFieldEditButton::class);
+			return $data->renderWith($template);
+		}
+		return parent::getColumnContent($gridField, $record, $columnName);
+	}
+}

src/Form/GridField/Config_RecordEditor.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace zauberfisch\PersistentDataObject\Form\GridField;
+
+use zauberfisch\PersistentDataObject\Form\GridField\Action\EditButton;
+use zauberfisch\PersistentDataObject\Form\GridField\Filter\HideDeletedFilter;
+use zauberfisch\PersistentDataObject\Form\GridField\Filter\LatestVersionFilter;
+
+class Config_RecordEditor extends \GridFieldConfig_RecordEditor {
+	public function __construct($itemsPerPage = null) {
+		parent::__construct($itemsPerPage);
+		$this->removeComponentsByType(\GridFieldDetailForm::class);
+		$this->addComponent(new DetailForm());
+		$this->removeComponentsByType(\GridFieldEditButton::class);
+		$this->addComponent(new EditButton());
+		$this->addComponent(new LatestVersionFilter());
+		$this->addComponent(new HideDeletedFilter());
+	}
+}

src/Form/GridField/DetailForm.php

@@ -0,0 +1,59 @@
+<?php
+
+namespace zauberfisch\PersistentDataObject\Form\GridField;
+
+use zauberfisch\PersistentDataObject\Model\VersionedDataObjectExtension;
+
+class DetailForm extends \GridFieldDetailForm {
+	public function getURLHandlers($gridField) {
+		return array_merge([
+			'version-group/$VersionGroupID/item/$ID' => 'handleVersionedItem',
+		], parent::getURLHandlers($gridField));
+	}
+
+	/**
+	 * @param \GridField $gridField
+	 * @param \SS_HTTPRequest $request
+	 * @return \GridFieldDetailForm_ItemRequest|\RequestHandler
+	 */
+	public function handleVersionedItem($gridField, $request) {
+		// Our getController could either give us a true Controller, if this is the top-level GridField.
+		// It could also give us a RequestHandler in the form of GridFieldDetailForm_ItemRequest if this is a
+		// nested GridField.
+		$requestHandler = $gridField->getForm()->getController();
+
+		$versionedID = $request->param('VersionGroupID');
+		$id = $request->param('ID');
+
+		if ($versionedID && is_numeric($versionedID)) {
+			/** @var \DataList $list */
+			$list = $gridField->getList();
+			$list = $list->filter('VersionGroupID', $versionedID);
+			if ($id && is_numeric($id)) {
+				/** @var \DataObject|\PersistentDataObject_Model_DataObject|VersionedDataObjectExtension $record */
+				$record = $list->byID($id);
+			} else {
+				$record = $list->filter('VersionGroupLatest', true)->first();
+			}
+		} else {
+			$record = \Object::create($gridField->getModelClass());
+		}
+		$class = $this->getItemRequestClass();
+		/** @var DetailForm_ItemRequest $handler */
+		$handler = \Object::create($class, $gridField, $this, $record, $requestHandler, $this->name);
+		$handler->setTemplate($this->template);
+
+		// if no validator has been set on the GridField and the record has a CMS validator, use that.
+		if (!$this->getValidator()
+			&& (
+				method_exists($record, 'getCMSValidator')
+				|| $record instanceof \Object && $record->hasMethod('getCMSValidator')
+			)
+		) {
+			/** @noinspection PhpUndefinedMethodInspection */
+			$this->setValidator($record->getCMSValidator());
+		}
+		return $handler->handleRequest($request, \DataModel::inst());
+	}
+
+}

src/Form/GridField/DetailForm_ItemRequest.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace zauberfisch\PersistentDataObject\Form\GridField;
+
+use zauberfisch\PersistentDataObject\Model\VersionedDataObjectExtension;
+
+class DetailForm_ItemRequest extends \GridFieldDetailForm_ItemRequest {
+	private static $allowed_actions = [
+		'edit',
+		'view',
+		'ItemEditForm',
+	];
+
+	public function Link($action = null) {
+		$r = $this->record;
+		if ($r && $r->hasExtension(VersionedDataObjectExtension::class)) {
+			/** @var \DataObject|VersionedDataObjectExtension $r */
+			return \Controller::join_links(
+				$this->gridField->Link('version-group'),
+				$r->VersionGroupID ?: 'new',
+				'item',
+				$r->isLatestVersion(true) ? 'latest' : $r->ID,
+				$action
+			);
+		}
+		return parent::Link($action);
+	}
+}

src/Form/GridField/Filter/HideDeletedFilter.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace zauberfisch\PersistentDataObject\Form\GridField\Filter;
+
+class HideDeletedFilter implements \GridField_DataManipulator {
+	/**
+	 * @param \GridField $gridField
+	 * @param \SS_List|\DataList|\ArrayList $dataList
+	 * @return mixed
+	 */
+	public function getManipulatedData(\GridField $gridField, \SS_List $dataList) {
+		$latest = $dataList->filter('VersionGroupLatest', true);
+		$groupIDs = array_merge(
+			[0],
+			$latest->exclude('Deleted', 1)->column('VersionGroupID')
+		);
+		return $dataList->filter('VersionGroupID', $groupIDs);
+	}
+}

src/Form/GridField/Filter/LatestVersionFilter.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace zauberfisch\PersistentDataObject\Form\GridField\Filter;
+
+class LatestVersionFilter implements \GridField_DataManipulator {
+	/**
+	 * @param \GridField $gridField
+	 * @param \SS_List|\DataList|\ArrayList $dataList
+	 * @return mixed
+	 */
+	public function getManipulatedData(\GridField $gridField, \SS_List $dataList) {
+		return $dataList->filter('VersionGroupLatest', true);
+	}
+}

src/Model/DataObject.php

@@ -0,0 +1,119 @@
+<?php
+
+//namespace zauberfisch\PersistentDataObject\Model;
+
+/**
+ * DataObject classes can not be namespaced in SilverStripe 3.x
+ * @author zauberfisch
+ * @property boolean $Deleted
+ * @property int $VersionGroupID
+ * @property boolean $VersionGroupLatest
+ */
+class PersistentDataObject_Model_DataObject extends \DataObject {
+	private static $db = [
+		'Deleted' => 'Boolean',
+		'VersionGroupID' => 'Int',
+		'VersionGroupLatest' => 'Boolean',
+	];
+	private static $defaults = [
+		'VersionGroupLatest' => true,
+	];
+
+	public function requireTable() {
+		parent::requireTable();
+	}
+
+
+	public function getCMSFields() {
+		$return = new FieldList([
+			new TabSet('Root'),
+		]);
+		$return->addFieldsToTab('Root', [
+			new Tab('Main', _t(self::class . '.MainTab', 'Main')),
+		]);
+		$s = new FormScaffolder($this);
+		$return->addFieldsToTab('Root.Main', $s->getFieldList()->toArray());
+		$return->removeByName('Deleted');
+		$return->removeByName('VersionGroupID');
+		$return->removeByName('VersionGroupLatest');
+		return $return;
+	}
+
+	public function delete() {
+		$this->extend('onBeforeMarkDeleted');
+		$this->Deleted = true;
+		$this->write();
+		$this->flushCache();
+		$this->extend('onAfterMarkDeleted');
+	}
+
+	public function purge() {
+		$this->extend('onBeforePurge');
+		parent::delete();
+		$this->extend('onAfterPurge');
+	}
+
+	public function canDelete($member = null) {
+		return $this->isDeleted() ? false : parent::canDelete($member);
+	}
+
+	public function canPurge($member = null) {
+		// only allow purging a record if it has been marked as deleted, making deletion a 2 step process
+		return $this->isDeleted() ? parent::canDelete($member) : false;
+	}
+
+	public function canEdit($member = null) {
+		return $this->isDeleted() ? false : parent::canEdit($member);
+	}
+
+	public function isDeleted() {
+		$result = (bool)$this->Deleted;
+		$results = $this->extend('isDeleted');
+		if ($results && is_array($results)) {
+			// Remove NULLs
+			$results = array_filter($results, function ($v) {
+				return !is_null($v);
+			});
+			// If there are any non-NULL responses, then return the lowest one of them.
+			// If any explicitly deny the permission, then we don't get access
+			if ($results) {
+				$result = (bool)min($results);
+			}
+		}
+		return $result;
+	}
+
+	protected function writeBaseRecord($baseTable, $now) {
+		$this->extend('onBeforeWriteBaseRecord', $baseTable, $now);
+		parent::writeBaseRecord($baseTable, $now);
+		$this->onAfterWriteBaseRecord($baseTable, $now);
+		$this->extend('onAfterWriteBaseRecord', $baseTable, $now);
+	}
+
+	public function onAfterWriteBaseRecord($baseTable, $now) {
+		if (!$this->owner->getRawFieldData('VersionGroupID')) {
+			$id = $this->owner->getRawFieldData('ID');
+			$this->owner->setRawFieldData('VersionGroupID', $id);
+			(new \SQLUpdate('"' . $baseTable . '"'))
+				->assign('"VersionGroupID"', $id)
+				//->assign('"VersionGroupLatest"', 1)
+				->addWhere(['"ID"' => $id])
+				->execute();
+		}
+	}
+
+	protected function onBeforeWrite() {
+		parent::onBeforeWrite();
+		$this->owner->setRawFieldData('VersionGroupLatest', 1);
+	}
+
+
+	public function setRawFieldData($name, $value) {
+		$this->record[$name] = $value;
+		return $this;
+	}
+
+	public function getRawFieldData($name) {
+		return isset($this->record[$name]) ? $this->record[$name] : null;
+	}
+}