From 9f4e1e852ede46b7c9cda8d6a8c72d6fb302d2ef Mon Sep 17 00:00:00 2001
From: surbhigarg92 <surbhigarg.92@gmail.com>
Date: Tue, 24 Dec 2024 16:19:48 +0530
Subject: [PATCH] chore: Improve error message for Read-only transaction with
 bounded staleness

---
 src/database.ts  | 13 +++++++++++++
 test/database.ts | 24 ++++++++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/src/database.ts b/src/database.ts
index a81c5cfd5..5b45ba51d 100644
--- a/src/database.ts
+++ b/src/database.ts
@@ -2087,6 +2087,19 @@ class Database extends common.GrpcServiceObject {
         ? (optionsOrCallback as TimestampBounds)
         : {};
 
+    if ('maxStaleness' in options || 'minReadTimestamp' in options) {
+      const error = Object.assign(
+        new Error(
+          'maxStaleness / minReadTimestamp is not supported for multi-use read-only transactions.'
+        ),
+        {
+          code: 3, // invalid argument
+        }
+      ) as ServiceError;
+      callback!(error);
+      return;
+    }
+
     return startTrace('Database.getSnapshot', this._traceConfig, span => {
       this.pool_.getSession((err, session) => {
         if (err) {
diff --git a/test/database.ts b/test/database.ts
index d12eb3a13..9e3b6db7c 100644
--- a/test/database.ts
+++ b/test/database.ts
@@ -2305,6 +2305,30 @@ describe('Database', () => {
       assert.strictEqual(bounds, fakeTimestampBounds);
     });
 
+    it('should throw error if maxStaleness is passed in the timestamp bounds to the snapshot', () => {
+      const fakeTimestampBounds = {maxStaleness: 10};
+
+      database.getSnapshot(fakeTimestampBounds, err => {
+        assert.strictEqual(err.code, 3);
+        assert.strictEqual(
+          err.message,
+          'maxStaleness / minReadTimestamp is not supported for multi-use read-only transactions.'
+        );
+      });
+    });
+
+    it('should throw error if minReadTimestamp is passed in the timestamp bounds to the snapshot', () => {
+      const fakeTimestampBounds = {minReadTimestamp: 10};
+
+      database.getSnapshot(fakeTimestampBounds, err => {
+        assert.strictEqual(err.code, 3);
+        assert.strictEqual(
+          err.message,
+          'maxStaleness / minReadTimestamp is not supported for multi-use read-only transactions.'
+        );
+      });
+    });
+
     it('should begin a snapshot', () => {
       beginSnapshotStub.callsFake(() => {});