support @CacheKey() on getter

src/decorators.ts

@@ -22,18 +22,27 @@ const DrainKey =
   (
     fun: ObjectAndKeyFunction<T> = defaultValue,
   ): PropertyDecorator & TypedMethodDecorator<ObjectFunction<T>> =>
-  (obj, key, des?) => {
+  (target: any, key: string, descriptor?: PropertyDescriptor) => {
     let cb: ObjectFunction<T>;
-    if (des) {
-      // method decorator
-      // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-      // @ts-ignore
-      cb = async (o) => fun(await o[key](), key);
+
+    if (descriptor) {
+      // method decorator: descriptor.value
+      if (typeof descriptor.value === 'function') {
+        cb = async (o) => fun(await descriptor.value.call(o), key);
+      }
+      // getter/accessor decorator: descriptor.get
+      else if (typeof descriptor.get === 'function') {
+        cb = async (o) => fun(await descriptor.get.call(o), key);
+      } else {
+        // unlikely: setter-only accessor etc.
+        cb = async (o) => fun(await (o as any)[key], key);
+      }
     } else {
       // property decorator
-      cb = (o) => fun(o[key], key);
+      cb = (o) => fun((o as any)[key], key);
     }
-    return decoratorFactory(cb)(obj.constructor);
+
+    return decoratorFactory(cb)((target as any).constructor);
   };
 
 export const CacheKey = DrainKey<string>(

tests/sample.spec.ts

@@ -205,4 +205,37 @@ describe('Aragami.', () => {
     expect(_task2.id).toBe(1);
     await expect(aragami.queueLength(Task)).resolves.toBe(0);
   });
+
+  it('should support @CacheKey() on getter', async () => {
+    @CachePrefix('profile')
+    @CacheTTL(100)
+    class Profile {
+      id!: number;
+      name!: string;
+
+      @CacheKey()
+      get cacheKey() {
+        return `id.${this.id}`;
+      }
+    }
+
+    await aragami.clear(Profile);
+
+    const p = new Profile();
+    p.id = 42;
+    p.name = 'Karin';
+
+    await expect(aragami.set(p)).resolves.toEqual(p);
+
+    // key derived from getter
+    await expect(aragami.has(p)).resolves.toBeTruthy();
+    await expect(aragami.has(Profile, 'id.42')).resolves.toBeTruthy();
+    await expect(aragami.has('profile', 'id.42')).resolves.toBeTruthy();
+
+    const got = await aragami.get(Profile, 'id.42');
+    expect(got).toBeInstanceOf(Profile);
+    expect(got).toEqual({ id: 42, name: 'Karin' });
+
+    await expect(aragami.keys(Profile)).resolves.toEqual(['id.42']);
+  });
 });