SERVER-29434 Don't accept empty timestamps for readConcern afterClusterTime

3 files changed, 117 insertions, 0 deletions

diff --git a/buildscripts/resmokeconfig/suites/sharding_last_stable_mongos_and_mixed_shards.yml b/buildscripts/resmokeconfig/suites/sharding_last_stable_mongos_and_mixed_shards.yml
index 1aca6af1d0c..9103cef9bf9 100644
--- a/buildscripts/resmokeconfig/suites/sharding_last_stable_mongos_and_mixed_shards.yml
+++ b/buildscripts/resmokeconfig/suites/sharding_last_stable_mongos_and_mixed_shards.yml
@@ -22,6 +22,7 @@ selector:
   # New feature in v3.6 mongos and mongod.
   - jstests/sharding/logical_time_api.js
   - jstests/sharding/operation_time_api.js
+  - jstests/sharding/after_cluster_time.js
   - jstests/sharding/auth_drop_user_while_logged_in.js
   # New feature in v3.6 mongo shell.
   - jstests/sharding/causal_consistency_shell_support.js
diff --git a/jstests/sharding/after_cluster_time.js b/jstests/sharding/after_cluster_time.js
new file mode 100644
index 00000000000..0b299408512
--- /dev/null
+++ b/jstests/sharding/after_cluster_time.js
@@ -0,0 +1,111 @@
+/**
+ * Tests readConcern: afterClusterTime behavior in a sharded cluster.
+ */
+(function() {
+    "use strict";
+
+    load("jstests/replsets/rslib.js");  // For startSetIfSupportsReadMajority.
+
+    function assertAfterClusterTimeReadFailsWithCode(db, readConcernObj, errorCode) {
+        return assert.commandFailedWithCode(
+            db.runCommand({find: "foo", readConcern: readConcernObj}),
+            errorCode,
+            "expected command with read concern options: " + tojson(readConcernObj) + " to fail");
+    }
+
+    function assertAfterClusterTimeReadSucceeds(db, readConcernObj) {
+        return assert.commandWorked(db.runCommand({find: "foo", readConcern: readConcernObj}),
+                                    "expected command with read concern options: " +
+                                        tojson(readConcernObj) + " to succeed");
+    }
+
+    const rst = new ReplSetTest({
+        nodes: 1,
+        nodeOptions: {
+            enableMajorityReadConcern: "",
+            shardsvr: "",
+        }
+    });
+
+    if (!startSetIfSupportsReadMajority(rst)) {
+        jsTestLog("Skipping test since storage engine doesn't support majority read concern.");
+        return;
+    }
+    rst.initiate();
+
+    // Start the sharding test and add the majority read concern enabled replica set.
+    const st = new ShardingTest({
+        manualAddShard: true,
+    });
+    assert.commandWorked(st.s.adminCommand({addShard: rst.getURL()}));
+
+    const testDB = st.s.getDB("test");
+
+    // Insert some data to find later.
+    assert.commandWorked(testDB.runCommand(
+        {insert: "foo", documents: [{_id: 1, x: 1}], writeConcern: {w: "majority"}}));
+
+    // Test the afterClusterTime API without causal consistency enabled on the mongo connection.
+
+    // Reads with afterClusterTime require read concern level majority.
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {afterClusterTime: Timestamp(1, 1)}, ErrorCodes.InvalidOptions);
+
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "local", afterClusterTime: Timestamp(1, 1)}, ErrorCodes.InvalidOptions);
+
+    // Reads with afterClusterTime require a non-zero timestamp.
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "majority", afterClusterTime: {}}, ErrorCodes.TypeMismatch);
+
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "majority", afterClusterTime: 10}, ErrorCodes.TypeMismatch);
+
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "majority", afterClusterTime: Timestamp()}, ErrorCodes.InvalidOptions);
+
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "majority", afterClusterTime: Timestamp(0, 0)}, ErrorCodes.InvalidOptions);
+
+    // Reads with proper afterClusterTime arguments return committed data after the given time.
+    let res = assert.commandWorked(testDB.runCommand(
+        {find: "foo", readConcern: {level: "majority", afterClusterTime: Timestamp(1, 1)}}));
+
+    assert.eq(res.cursor.firstBatch,
+              [{_id: 1, x: 1}],
+              "expected afterClusterTime read to return the committed document");
+
+    // Test the afterClusterTime API with causal consistency enabled on the mongo connection.
+    testDB.getMongo().setCausalConsistency(true);
+
+    // With causal consistency enabled, the shell sets read concern to level "majority" if it is not
+    // specified.
+    assertAfterClusterTimeReadSucceeds(testDB, {afterClusterTime: Timestamp(1, 1)});
+
+    // Read concern levels other than majority are still not accepted.
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "local", afterClusterTime: Timestamp(1, 1)}, ErrorCodes.InvalidOptions);
+
+    // Reads with afterClusterTime still require a non-zero timestamp.
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "majority", afterClusterTime: {}}, ErrorCodes.TypeMismatch);
+
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "majority", afterClusterTime: 10}, ErrorCodes.TypeMismatch);
+
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "majority", afterClusterTime: Timestamp()}, ErrorCodes.InvalidOptions);
+
+    assertAfterClusterTimeReadFailsWithCode(
+        testDB, {level: "majority", afterClusterTime: Timestamp(0, 0)}, ErrorCodes.InvalidOptions);
+
+    // Reads with proper afterClusterTime arguments return committed data after the given time.
+    res = assert.commandWorked(testDB.runCommand(
+        {find: "foo", readConcern: {level: "majority", afterClusterTime: Timestamp(1, 1)}}));
+
+    assert.eq(res.cursor.firstBatch,
+              [{_id: 1, x: 1}],
+              "expected afterClusterTime read to return the committed document");
+
+    st.stop();
+})();
diff --git a/src/mongo/db/repl/read_concern_args.cpp b/src/mongo/db/repl/read_concern_args.cpp
index 2352547deb5..fc85048d4b4 100644
--- a/src/mongo/db/repl/read_concern_args.cpp
+++ b/src/mongo/db/repl/read_concern_args.cpp
@@ -172,6 +172,11 @@ Status ReadConcernArgs::initialize(const BSONElement& readConcernElem) {
                                     << kMajorityReadConcernStr);
     }
 
+    if (_clusterTime && _clusterTime == LogicalTime::kUninitialized) {
+        return Status(ErrorCodes::InvalidOptions,
+                      str::stream() << kAfterClusterTimeFieldName << " cannot be a null timestamp");
+    }
+
     return Status::OK();
 }