From e4e687dd1889abdb84329c0cf368e944c5b799ba Mon Sep 17 00:00:00 2001
From: Neal Beeken <neal.beeken@mongodb.com>
Date: Thu, 4 Apr 2024 13:43:22 -0400
Subject: [PATCH 1/2] fix(NODE-6066): signature can be optional at runtime

---
 src/sdam/common.ts            | 10 ++++++++--
 test/types/sessions.test-d.ts | 10 ++++++++--
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/sdam/common.ts b/src/sdam/common.ts
index e4b84d83f6e..fab8124d4c6 100644
--- a/src/sdam/common.ts
+++ b/src/sdam/common.ts
@@ -55,10 +55,16 @@ export function drainTimerQueue(queue: TimerQueue): void {
   queue.clear();
 }
 
-/** @public */
+/**
+ * @public
+ * Gossiped in component for the cluster time tracking the state of user databases
+ * across the cluster. It may optionally include a signature identifying the process that
+ * generated such a value.
+ */
 export interface ClusterTime {
   clusterTime: Timestamp;
-  signature: {
+  /** Used to validate the identity of a request or response's ClusterTime. */
+  signature?: {
     hash: Binary;
     keyId: Long;
   };
diff --git a/test/types/sessions.test-d.ts b/test/types/sessions.test-d.ts
index 48c8fcb0dc5..7865f416339 100644
--- a/test/types/sessions.test-d.ts
+++ b/test/types/sessions.test-d.ts
@@ -1,6 +1,6 @@
-import { expectError, expectType } from 'tsd';
+import { expectAssignable, expectDocCommentIncludes, expectError, expectType } from 'tsd';
 
-import type { ClientSession } from '../mongodb';
+import type { Binary, ClientSession, ClusterTime, Long, Timestamp } from '../mongodb';
 import { MongoClient, ReadConcern, ReadConcernLevel } from '../mongodb';
 
 // test mapped cursor types
@@ -25,3 +25,9 @@ const unknownFn: () => Promise<unknown> = async () => 2;
 expectType<unknown>(await client.withSession(unknownFn));
 // Not a promise returning function
 expectError(await client.withSession(() => null));
+
+declare const ct: ClusterTime;
+expectType<Timestamp>(ct.clusterTime);
+expectAssignable<ClusterTime['signature']>(undefined);
+expectType<Binary>(ct.signature?.hash);
+expectType<Long>(ct.signature?.keyId);

From d9769ad2944bb7243473ec7fab8d24d13fe19ca7 Mon Sep 17 00:00:00 2001
From: Neal Beeken <neal.beeken@mongodb.com>
Date: Thu, 4 Apr 2024 14:28:45 -0400
Subject: [PATCH 2/2] fix: lint

---
 test/types/sessions.test-d.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/types/sessions.test-d.ts b/test/types/sessions.test-d.ts
index 7865f416339..ec6f5a1bf33 100644
--- a/test/types/sessions.test-d.ts
+++ b/test/types/sessions.test-d.ts
@@ -1,4 +1,4 @@
-import { expectAssignable, expectDocCommentIncludes, expectError, expectType } from 'tsd';
+import { expectAssignable, expectError, expectType } from 'tsd';
 
 import type { Binary, ClientSession, ClusterTime, Long, Timestamp } from '../mongodb';
 import { MongoClient, ReadConcern, ReadConcernLevel } from '../mongodb';
@@ -29,5 +29,5 @@ expectError(await client.withSession(() => null));
 declare const ct: ClusterTime;
 expectType<Timestamp>(ct.clusterTime);
 expectAssignable<ClusterTime['signature']>(undefined);
-expectType<Binary>(ct.signature?.hash);
-expectType<Long>(ct.signature?.keyId);
+expectType<Binary | undefined>(ct.signature?.hash);
+expectType<Long | undefined>(ct.signature?.keyId);