feat(server-cache): estimatedSize (#23)

__tests__/intl/server-cache.spec.js

@@ -17,6 +17,7 @@ import lolex from 'lolex';
 describe('server-cache', () => {
   let set;
   let get;
+  let getEstimatedSize;
   let clock;
   let intervalUnref;
 
@@ -37,9 +38,11 @@ describe('server-cache', () => {
     };
 
     jest.resetModules();
+    // eslint-disable-next-line global-require
     const serverCache = require('../../src/intl/server-cache');
     set = serverCache.set;
     get = serverCache.get;
+    getEstimatedSize = serverCache.getEstimatedSize;
   }
 
   beforeEach(() => {
@@ -91,6 +94,16 @@ describe('server-cache', () => {
     });
   });
 
+  describe('getEstimatedSize', () => {
+    it('returns memory allocation of cache', () => {
+      delete process.env.NODE_ENV;
+      setupCache();
+      expect(getEstimatedSize()).toEqual(0);
+      set('add entry to cache', 'entry');
+      expect(getEstimatedSize()).toBe(82);
+    });
+  });
+
   describe('cleanup', () => {
     it('leaves non-expired values in cache', () => {
       setupCache();

package.json

@@ -54,10 +54,11 @@
     ]
   },
   "dependencies": {
+    "holocron": "^1.0.0",
     "immutable": "^4.0.0-rc.12",
     "js-cookie": "^2.2.0",
-    "holocron": "^1.0.0-9",
     "lean-intl": "^4.2.2",
+    "object-sizeof": "^1.6.1",
     "reselect": "^4.0.0"
   },
   "devDependencies": {

src/intl/server-cache.js

@@ -12,6 +12,8 @@
  * under the License.
  */
 
+import sizeOf from 'object-sizeof';
+
 const cache = new Map();
 
 const CLEANUP_INTERVAL = 10 * 60 * 1e3; // intended to be 10 minutes
@@ -35,9 +37,12 @@ function get(url) {
   return cached.data;
 }
 
+const getEstimatedSize = () => sizeOf(Object.fromEntries(cache));
+
 export {
   set,
   get,
+  getEstimatedSize,
 };
 
 function cleanup() {