feat(NODE-5035): cleanup cache ono each request

Author: durran

src/cmap/auth/mongodb_oidc/callback_workflow.ts

@@ -131,6 +131,8 @@ export class CallbackWorkflow implements Workflow {
   ): Promise<Document> {
     // Call the request callback.
     const request = credentials.mechanismProperties.REQUEST_TOKEN_CALLBACK;
+    // Always clear expired entries from the cache on each finish as cleanup.
+    this.cache.deleteExpiredEntries();
     if (request) {
       const tokenResult = await request(credentials.username, stepOneResult, TIMEOUT);
       // Cache a new entry and continue with the saslContinue.

src/cmap/auth/mongodb_oidc/token_entry_cache.ts

@@ -29,6 +29,7 @@ export class TokenEntry {
    * 5 minutes from the expiration time.
    */
   isValid() {
+    console.log(this.expiration);
     return this.expiration - Date.now() > EXPIRATION_BUFFER;
   }
 }
@@ -82,6 +83,17 @@ export class TokenEntryCache {
   getEntry(address: string, username = ''): TokenEntry | undefined {
     return this.entries.get(cacheKey(address, username));
   }
+
+  /**
+   * Delete all expired entries from the cache.
+   */
+  deleteExpiredEntries(): void {
+    this.entries.forEach((entry, key, entries) => {
+      if (!entry.isValid()) {
+        entries.delete(key);
+      }
+    });
+  }
 }
 
 /**

test/unit/cmap/auth/mongodb_oidc/token_entry_cache.test.ts

@@ -64,6 +64,25 @@ describe('TokenEntryCache', function () {
     });
   });
 
+  describe('#deleteExpiredEntries', function () {
+    const cache = new TokenEntryCache();
+
+    const nonExpiredResult = {
+      accessToken: 'test',
+      expiresInSeconds: 600
+    };
+
+    before(function () {
+      cache.addEntry(tokenResult, serverResult, 'localhost', 'user');
+      cache.addEntry(nonExpiredResult, serverResult, 'localhost', 'user2');
+      cache.deleteExpiredEntries();
+    });
+
+    it('deletes all expired tokens from the cache', function () {
+      expect(cache.entries.size).to.equal(1);
+    });
+  });
+
   describe('#deleteEntry', function () {
     const cache = new TokenEntryCache();