CustomVariable(Boolean|Null|Number): provide JSON

library/Director/CustomVariable/CustomVariableBoolean.php

@@ -16,6 +16,11 @@ class CustomVariableBoolean extends CustomVariable
         return 'json';
     }
 
+    public function getDbValue()
+    {
+        return json_encode($this->getValue());
+    }
+
     public function getValue()
     {
         return $this->value;

library/Director/CustomVariable/CustomVariableNull.php

@@ -17,6 +17,11 @@ class CustomVariableNull extends CustomVariable
         return null;
     }
 
+    public function getDbValue()
+    {
+        return json_encode($this->getValue());
+    }
+
     public function getDbFormat()
     {
         return 'json';

library/Director/CustomVariable/CustomVariableNumber.php

@@ -29,6 +29,11 @@ class CustomVariableNumber extends CustomVariable
         return 'json';
     }
 
+    public function getDbValue()
+    {
+        return json_encode($this->getValue());
+    }
+
     public function getValue()
     {
         return $this->value;