Introduce matchesOn & isMatchedOn methods

library/Icingadb/Authentication/ObjectAuthorization.php

@@ -23,6 +23,13 @@ class ObjectAuthorization
     /** @var array */
     protected static $knownGrants = [];
 
+    /**
+     * Caches already applied filters to an object
+     *
+     * @var array
+     */
+    protected static $matchedFilters = [];
+
     /**
      * Check whether the permission is granted on the object
      *
@@ -88,6 +95,43 @@ class ObjectAuthorization
         return $self->checkGrants($permission, self::$knownGrants[$type][$uniqueId]);
     }
 
+    /**
+     * Check whether the given filter matches on the given object
+     *
+     * @param string $queryString
+     * @param Model  $object
+     *
+     * @return bool
+     */
+    public static function matchesOn(string $queryString, Model $object): bool
+    {
+        $self = new static();
+
+        $uniqueId = $object->{$object->getKeyName()};
+        if (! isset(self::$matchedFilters[$queryString][$uniqueId])) {
+            $restriction = 'icingadb/filter/services';
+            if ($object instanceof Host) {
+                $restriction = 'icingadb/filter/hosts';
+            }
+
+            $filter = $self->parseRestriction($queryString, $restriction);
+
+            $query = $object::on($self->getDb());
+            $query
+                ->filter($filter)
+                ->filter(Filter::equal($object->getKeyName(), $uniqueId))
+                ->getSelectBase()
+                ->columns([new Expression('1')]);
+
+            $result = $query->execute()->hasResult();
+            self::$matchedFilters[$queryString][$uniqueId] = $result;
+
+            return $result;
+        }
+
+        return self::$matchedFilters[$queryString][$uniqueId];
+    }
+
     /**
      * Load all the user's roles that grant access to at least one object matching the filter
      *

library/Icingadb/Common/Auth.php

@@ -85,6 +85,19 @@ trait Auth
         return ObjectAuthorization::grantsOnType($permission, $type, $filter, $cache);
     }
 
+    /**
+     * Check whether the filter matches the given object
+     *
+     * @param string $queryString
+     * @param Model  $object
+     *
+     * @return bool
+     */
+    public function isMatchedOn(string $queryString, Model $object): bool
+    {
+        return ObjectAuthorization::matchesOn($queryString, $object);
+    }
+
     /**
      * Apply Icinga DB Web's restrictions depending on what is queried
      *
@@ -211,7 +224,7 @@ trait Auth
                     $where = $queryClone->getSelectBase()->getWhere();
 
                     $values = [];
-                    $rendered = $this->getDb()->getQueryBuilder()->buildCondition($where, $values);
+                    $rendered = $query->getDb()->getQueryBuilder()->buildCondition($where, $values);
                     $columns[$flatvaluePath] = new Expression(
                         "CASE WHEN (" . $rendered . ") THEN (%s) ELSE '***' END",
                         [$flatvalue],