fix: Using Parse Server option extendSessionOnUse does not correctly clear memory and functions as a debounce instead of a throttle

spec/Auth.spec.js

@@ -106,6 +106,8 @@ describe('Auth', () => {
         updatedAt: updatedAt.toISOString(),
       }
     );
+    Parse.Server.cacheController.clear();
+    await new Promise(resolve => setTimeout(resolve, 1000));
     await session.fetch();
     await new Promise(resolve => setTimeout(resolve, 1000));
     await session.fetch();

src/Auth.js

@@ -2,6 +2,7 @@
 import { isDeepStrictEqual } from 'util';
 import { getRequestObject, resolveError } from './triggers';
 import { logger } from './logger';
+import { LRUCache as LRU } from 'lru-cache';
 import RestQuery from './RestQuery';
 import RestWrite from './RestWrite';
 
@@ -67,6 +68,10 @@
   return new Auth({ config, isMaster: false });
 }
 
+const throttle = new LRU({
+  max: 10000,
+  ttl: 500,
+});
 /**
  * Checks whether session should be updated based on last update time & session length.
  */
@@ -78,44 +83,45 @@
   return lastUpdated <= skipRange;
 }
 
-const throttle = {};
 const renewSessionIfNeeded = async ({ config, session, sessionToken }) => {
   if (!config?.extendSessionOnUse) {
     return;
   }
-  clearTimeout(throttle[sessionToken]);
-  throttle[sessionToken] = setTimeout(async () => {
-    try {
-      if (!session) {
-        const query = await RestQuery({
-          method: RestQuery.Method.get,
-          config,
-          auth: master(config),
-          runBeforeFind: false,
-          className: '_Session',
-          restWhere: { sessionToken },
-          restOptions: { limit: 1 },
-        });
-        const { results } = await query.execute();
-        session = results[0];
-      }
-      if (!shouldUpdateSessionExpiry(config, session) || !session) {
-        return;
-      }
-      const expiresAt = config.generateSessionExpiresAt();
-      await new RestWrite(
+  if (throttle.get(sessionToken)) {
+    return;
+  }
+  throttle.set(sessionToken, true);
+  try {
+    if (!session) {
+      const query = await RestQuery({
+        method: RestQuery.Method.get,
         config,
-        master(config),
-        '_Session',
-        { objectId: session.objectId },
-        { expiresAt: Parse._encode(expiresAt) }
-      ).execute();
-    } catch (e) {
-      if (e?.code !== Parse.Error.OBJECT_NOT_FOUND) {
-        logger.error('Could not update session expiry: ', e);
-      }
+        auth: master(config),
+        runBeforeFind: false,
+        className: '_Session',
+        restWhere: { sessionToken },
+        restOptions: { limit: 1 },
+      });
+      const { results } = await query.execute();
+      session = results[0];
+    }
+
+    if (!shouldUpdateSessionExpiry(config, session) || !session) {
+      return;
     }
-  }, 500);
+    const expiresAt = config.generateSessionExpiresAt();
+    await new RestWrite(
+      config,
+      master(config),
+      '_Session',
+      { objectId: session.objectId },
+      { expiresAt: Parse._encode(expiresAt) }
+    ).execute();
+  } catch (e) {
+    if (e?.code !== Parse.Error.OBJECT_NOT_FOUND) {
+      logger.error('Could not update session expiry: ', e);
+    }
+  }
 };
 
 // Returns a promise that resolves to an Auth object