Datafield: on rename ask whether to also rename vars

fixes #818

application/controllers/DatafieldController.php

@@ -2,6 +2,7 @@
 
 namespace Icinga\Module\Director\Controllers;
 
+use Icinga\Module\Director\Forms\DirectorDatafieldForm;
 use Icinga\Module\Director\Web\Controller\ActionController;
 
 class DatafieldController extends ActionController
@@ -24,23 +25,23 @@ class DatafieldController extends ActionController
             $edit = true;
         }
 
-        $form = $this->view->form = $this->loadForm('directorDatafield')
+        $form = DirectorDatafieldForm::load()
             ->setSuccessUrl('director/data/fields')
             ->setDb($this->db());
 
         if ($edit) {
             $form->loadObject($id);
-            $this->view->title = sprintf(
+            $this->addTitle(
                 $this->translate('Modify %s'),
                 $form->getObject()->varname
             );
-            $this->singleTab($this->translate('Edit a field'));
+            $this->addSingleTab($this->translate('Edit a field'));
         } else {
-            $this->view->title = $this->translate('Add a new Data Field');
-            $this->singleTab($this->translate('New field'));
+            $this->addTitle($this->translate('Add a new Data Field'));
+            $this->addSingleTab($this->translate('New field'));
         }
 
         $form->handleRequest();
-        $this->render('object/form', null, true);
+        $this->content()->add($form);
     }
 }

application/forms/DirectorDatafieldForm.php

@@ -21,6 +21,15 @@ class DirectorDatafieldForm extends DirectorObjectForm
                 if ($cnt = CustomVariables::countAll($varname, $this->getDb())) {
                     $this->askForVariableDeletion($varname, $cnt);
                 }
+            } elseif ($this->shouldBeRenamed()) {
+                $varname = $this->object()->getOriginalProperty('varname');
+                if ($cnt = CustomVariables::countAll($varname, $this->getDb())) {
+                    $this->askForVariableRename(
+                        $varname,
+                        $this->getSentValue('varname'),
+                        $cnt
+                    );
+                }
             }
         }
 
@@ -70,6 +79,51 @@ class DirectorDatafieldForm extends DirectorObjectForm
         }
     }
 
+    protected function askForVariableRename($oldname, $newname, $cnt)
+    {
+        $msg = $this->translate(
+            'Leaving custom variables in place while renaming the related field is'
+            . ' perfectly legal and might be a desired operation. This way you can'
+            . ' no longer modify related custom variables in the Director GUI, but'
+            . ' the variables themselves will stay there and continue to be deployed.'
+            . ' When you re-add a field for the same variable later on, everything'
+            . ' will continue to work as before'
+        );
+
+        $this->addBoolean('rename_vars', array(
+            'label'       => $this->translate('Rename related vars'),
+            'description' => sprintf($msg, $this->getSentValue('varname')),
+            'required'    => true,
+        ));
+
+        if ($wipe = $this->getSentValue('rename_vars')) {
+            if ($wipe === 'y') {
+                CustomVariables::renameAll($oldname, $newname, $this->getDb());
+            }
+        } else {
+            $this->abortDeletion();
+            $this->addError(
+                sprintf(
+                    $this->translate('Also rename all "%s" custom variables to "%s" on %d objects?'),
+                    $oldname,
+                    $newname,
+                    $cnt
+                )
+            );
+            $this->getElement('rename_vars')->addError(
+                sprintf(
+                    $this->translate(
+                        'There are %d objects with a related property. Should I also'
+                        . ' rename the "%s" property to "%s" on them?'
+                    ),
+                    $cnt,
+                    $oldname,
+                    $newname
+                )
+            );
+        }
+    }
+
     public function setup()
     {
         $this->addHtmlHint(
@@ -128,11 +182,12 @@ class DirectorDatafieldForm extends DirectorObjectForm
         }
 
         try {
+            $object = $this->object();
             if ($class = $this->getSentValue('datatype')) {
                 if ($class && array_key_exists($class, $types)) {
                     $this->addSettings($class);
                 }
-            } elseif ($class = $this->object()->get('datatype')) {
+            } elseif ($class = $object->get('datatype')) {
                 $this->addSettings($class);
             }
 
@@ -142,7 +197,7 @@ class DirectorDatafieldForm extends DirectorObjectForm
             $this->getElement('datatype')->addError($e->getMessage());
         }
 
-        foreach ($this->object()->getSettings() as $key => $val) {
+        foreach ($object->getSettings() as $key => $val) {
             if ($el = $this->getElement($key)) {
                 $el->setValue($val);
             }
@@ -151,6 +206,13 @@ class DirectorDatafieldForm extends DirectorObjectForm
         $this->setButtons();
     }
 
+    public function shouldBeRenamed()
+    {
+        $object = $this->object();
+        return $object->hasBeenLoadedFromDb()
+            && $object->getOriginalProperty('varname') !== $this->getSentValue('varname');
+    }
+
     protected function addSettings($class = null)
     {
         if ($class === null) {

library/Director/CustomVariable/CustomVariables.php

@@ -61,6 +61,15 @@ class CustomVariables implements Iterator, Countable, IcingaConfigRenderer
         }
     }
 
+    public static function renameAll($oldname, $newname, Db $connection)
+    {
+        $db = $connection->getDbAdapter();
+        $where = $db->quoteInto('varname = ?', $oldname);
+        foreach (static::$allTables as $table) {
+            $db->update($table, ['varname' => $newname], $where);
+        }
+    }
+
     public function count()
     {
         $count = 0;

library/Director/Data/Db/DbObject.php

@@ -244,18 +244,23 @@ abstract class DbObject
             return $this->$func();
         }
 
-        if (! array_key_exists($property, $this->properties)) {
-            throw new IE('Trying to get invalid property "%s"', $property);
-        }
+        $this->assertPropertyExists($property);
         return $this->properties[$property];
     }
 
     public function getProperty($key)
+    {
+        $this->assertPropertyExists($key);
+        return $this->properties[$key];
+    }
+
+    protected function assertPropertyExists($key)
     {
         if (! array_key_exists($key, $this->properties)) {
             throw new IE('Trying to get invalid property "%s"', $key);
         }
-        return $this->properties[$key];
+
+        return $this;
     }
 
     public function hasProperty($key)
@@ -650,6 +655,16 @@ abstract class DbObject
         return $this->loadedProperties;
     }
 
+    public function getOriginalProperty($key)
+    {
+        $this->assertPropertyExists($key);
+        if ($this->hasBeenLoadedFromDb()) {
+            return $this->loadedProperties[$key];
+        }
+
+        return null;
+    }
+
     public function hasBeenLoadedFromDb()
     {
         return $this->loadedFromDb;