feat(enumeration): define valid values for a field

src/decorator/enumeration.js

@@ -0,0 +1,19 @@
+import {OrmMetadata} from '../orm-metadata';
+import {ensurePropertyIsConfigurable} from './utils';
+
+/**
+ * Registers the 'enumerations' for an attribute's values
+ *
+ * @param {*[]} values - a list of valid values for the entity's attribute
+ *
+ * @return {Function}
+ *
+ * @decorator
+ */
+export function enumeration(values) {
+  return function(target, propertyName, descriptor) {
+    ensurePropertyIsConfigurable(target, propertyName, descriptor);
+
+    OrmMetadata.forTarget(target.constructor).put('enumerations', propertyName, values);
+  };
+}