1 files changed, 76 insertions, 0 deletions
diff --git a/jstests/sharding/append_oplog_note_mongos.js b/jstests/sharding/append_oplog_note_mongos.js
new file mode 100644
index 00000000000..1369ecb06be
--- /dev/null
+++ b/jstests/sharding/append_oplog_note_mongos.js
@@ -0,0 +1,76 @@
+/**
+ * Tests that the 'appendOplogNote' command on mongos correctly performs a no-op write on each
+ * shard and advances the $clusterTime.
+ */
+
+(function() {
+"use strict";
+
+load("jstests/libs/fail_point_util.js");
+
+function checkOplogEntry(actualOplogEntry) {
+    const {op, o} = actualOplogEntry;
+    assert.eq({op, o}, {op: "n", o: {a: 2}}, actualOplogEntry);
+}
+
+// We need to disable the periodic no-op writer so we can verify that the 'appendOplogNote'
+// no-op is the latest operation on the oplog.
+const st = new ShardingTest(
+    {mongos: 1, shards: 2, rs: {nodes: 2, setParameter: {writePeriodicNoops: false}}});
+const admin = st.getDB('admin');
+const shardOnePrimary = st.rs0.getPrimary();
+const shardTwoPrimary = st.rs1.getPrimary();
+
+// Test that issuing the command without the 'data' field results in an error.
+let res = assert.commandFailed(admin.runCommand({appendOplogNote: 1}));
+assert.eq(res.code, ErrorCodes.NoSuchKey);
+assert(res.hasOwnProperty("raw"), res);
+
+// Test that the error response contains the correct fields.
+const appendOplogNoteFailpoint = configureFailPoint(shardOnePrimary, "failCommand", {
+    errorCode: ErrorCodes.HostUnreachable,
+    failCommands: ["appendOplogNote"],
+    failInternalCommands: true
+});
+
+res = assert.commandFailed(admin.runCommand({appendOplogNote: 1, data: {a: 1}}));
+assert(res.hasOwnProperty("errmsg"), res);
+assert.eq(res.code, ErrorCodes.HostUnreachable);
+assert(res.hasOwnProperty("raw"), res);
+
+appendOplogNoteFailpoint.wait();
+appendOplogNoteFailpoint.off();
+
+// Test that a successful 'appendOplogNote' command performs a no-op write and advances the
+// $clusterTime.
+const shardOneBefore =
+    assert.commandWorked(shardOnePrimary.getDB("admin").runCommand({replSetGetStatus: 1}));
+const shardTwoBefore =
+    assert.commandWorked(shardTwoPrimary.getDB("admin").runCommand({replSetGetStatus: 1}));
+
+res = assert.commandWorked(admin.runCommand({appendOplogNote: 1, data: {a: 2}}));
+assert(res.hasOwnProperty("raw"), res);
+
+const shardOneAfter =
+    assert.commandWorked(shardOnePrimary.getDB("admin").runCommand({replSetGetStatus: 1}));
+const shardTwoAfter =
+    assert.commandWorked(shardTwoPrimary.getDB("admin").runCommand({replSetGetStatus: 1}));
+
+assert.lt(shardOneBefore.members[0].optime.ts, shardOneAfter.members[0].optime.ts);
+assert.lt(shardTwoBefore.members[0].optime.ts, shardTwoAfter.members[0].optime.ts);
+
+let lastEntryShardOne =
+    shardOnePrimary.getDB("local").oplog.rs.find().sort({$natural: -1}).limit(1).toArray()[0];
+let lastEntryShardTwo =
+    shardTwoPrimary.getDB("local").oplog.rs.find().sort({$natural: -1}).limit(1).toArray()[0];
+
+// The $clusterTime in the 'replSetGetStatus' response should be equal to the timestamp of
+// 'appendOplogNote' command no-op write, which is the last operation on the shard oplogs.
+checkOplogEntry(lastEntryShardOne);
+checkOplogEntry(lastEntryShardTwo);
+
+assert.eq(shardOneAfter.members[0].optime.ts, lastEntryShardOne.ts);
+assert.eq(shardTwoAfter.members[0].optime.ts, lastEntryShardTwo.ts);
+
+st.stop();
+}());