Fix shallow copy of cached object

models/common.ts

@@ -1,6 +1,6 @@
 import * as TypeORM from "typeorm";
 import * as LRUCache from "lru-cache";
-import * as ObjectAssignDeep from "object-assign-deep";
+import * as DeepCopy from "deepcopy";
 
 interface Paginater {
   pageCnt: number;
@@ -41,27 +41,27 @@ export default class Model extends TypeORM.BaseEntity {
     if ((this as typeof Model).cache) {
       let result;
       if (result = cacheGet(this.name, id)) {
-        // Got cached result.
+        return result.clone();
-        // Return a copy of it to avoid issue of adding or assigning properties.
-        const object = {};
-        Object.keys(result).forEach(key => {
-          object[key] = result[key] && typeof result[key] === 'object'
-                      ? ObjectAssignDeep({}, result[key])
-                      : result[key];
-        });
-        return (this as typeof Model).create<T>(object);
       }
 
       result = await doQuery();
       if (result) {
         cacheSet(this.name, id, result);
       }
-      return result;
+      return result.clone();
     } else {
       return await doQuery();
     }
   }
 
+  clone() {
+    const object = {};
+    TypeORM.getConnection().getMetadata(this.constructor).ownColumns.map(column => column.propertyName).forEach(key => {
+      object[key] = DeepCopy(this[key]);
+    });
+    return (this.constructor as any).create(object);
+  }
+
   async destroy() {
     const id = (this as any).id;
     await TypeORM.getManager().remove(this);

package.json

@@ -34,6 +34,7 @@
     "command-line-args": "^5.1.0",
     "cookie-parser": "^1.4.4",
     "cssfilter": "0.0.10",
+    "deepcopy": "^2.0.0",
     "download": "^7.1.0",
     "ejs": "^2.5.2",
     "express": "^4.14.0",

yarn.lock

@@ -859,6 +859,13 @@ deep-is@~0.1.3:
   resolved "https://registry.yarnpkg.com/deep-is/-/deep-is-0.1.3.tgz#b369d6fb5dbc13eecf524f91b070feedc357cf34"
   integrity sha1-s2nW+128E+7PUk+RsHD+7cNXzzQ=
 
+deepcopy@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/deepcopy/-/deepcopy-2.0.0.tgz#2acb9b7645f9f54d815eee991455e790e72e2252"
+  integrity sha512-d5ZK7pJw7F3k6M5vqDjGiiUS9xliIyWkdzBjnPhnSeRGjkYOGZMCFkdKVwV/WiHOe0NwzB8q+iDo7afvSf0arA==
+  dependencies:
+    type-detect "^4.0.8"
+
 delayed-stream@~1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/delayed-stream/-/delayed-stream-1.0.0.tgz#df3ae199acadfb7d440aaae0b29e2272b24ec619"
@@ -3525,6 +3532,11 @@ type-check@~0.3.2:
   dependencies:
     prelude-ls "~1.1.2"
 
+type-detect@^4.0.8:
+  version "4.0.8"
+  resolved "https://registry.yarnpkg.com/type-detect/-/type-detect-4.0.8.tgz#7646fb5f18871cfbb7749e69bd39a6388eb7450c"
+  integrity sha512-0fr/mIH1dlO+x7TlcMy+bIDqKPsw/70tVyeHW787goQjhmqaZe10uwLujubK9q9Lg6Fiho1KUKDYz0Z7k7g5/g==
+
 type-is@^1.6.4, type-is@~1.6.16:
   version "1.6.16"
   resolved "https://registry.yarnpkg.com/type-is/-/type-is-1.6.16.tgz#f89ce341541c672b25ee7ae3c73dee3b2be50194"