Revert "SERVER-49987 Rename response fields if hello command is sent on mongod"

This reverts commit 7157e90233ddc3b1b208564a711289a2d99e5ee5.

6 files changed, 84 insertions, 198 deletions

diff --git a/etc/backports_required_for_multiversion_tests.yml b/etc/backports_required_for_multiversion_tests.yml
index b16fe6aabf9..a315ca74c90 100644
--- a/etc/backports_required_for_multiversion_tests.yml
+++ b/etc/backports_required_for_multiversion_tests.yml
@@ -75,8 +75,6 @@ all:
     test_file: jstests/sharding/log_remote_op_wait.js
   - ticket: SERVER-49987
     test_file: jstests/core/ismaster.js
-  - ticket: SERVER-49987
-    test_file: jstests/replsets/ismaster1.js
   - ticket: SERVER-49986
     test_file: jstests/core/views/views_all_commands.js
   - ticket: SERVER-49986
diff --git a/jstests/core/ismaster.js b/jstests/core/ismaster.js
index e9d5e344303..5f309b83392 100644
--- a/jstests/core/ismaster.js
+++ b/jstests/core/ismaster.js
@@ -14,16 +14,11 @@ function checkResponseFields(commandString) {
         "maxMessageSizeBytes possibly missing:" + tojson(res));
     assert(res.maxWriteBatchSize && isNumber(res.maxWriteBatchSize) && res.maxWriteBatchSize > 0,
            "maxWriteBatchSize possibly missing:" + tojson(res));
+    assert.eq("boolean", typeof res.ismaster, "ismaster field is not a boolean" + tojson(res));
 
-    if (commandString === "hello") {
-        assert.eq("boolean",
-                  typeof res.isWritablePrimary,
-                  "isWritablePrimary field is not a boolean" + tojson(res));
-        assert(res.isWritablePrimary === true, "isWritablePrimary field is false" + tojson(res));
-    } else {
-        assert.eq("boolean", typeof res.ismaster, "ismaster field is not a boolean" + tojson(res));
-        assert(res.ismaster === true, "ismaster field is false" + tojson(res));
-    }
+    // TODO SERVER-49987: Check for res.isWritablePrimary instead of res.ismaster if a hello command
+    // was executed.
+    assert(res.ismaster === true, "ismaster field is false" + tojson(res));
     assert(res.localTime, "localTime possibly missing:" + tojson(res));
     assert(res.connectionId, "connectionId missing or false" + tojson(res));
 
@@ -37,10 +32,9 @@ function checkResponseFields(commandString) {
             "passives",
             "arbiters",
             "primary",
-            "arbiterOnly",
+            "aribterOnly",
             "passive",
             "slaveDelay",
-            "secondaryDelaySecs",
             "hidden",
             "tags",
             "buildIndexes",
@@ -62,6 +56,8 @@ function checkResponseFields(commandString) {
     }
 }
 
-checkResponseFields("hello");
+// TODO SERVER-49987: add the "hello" command test back in once mongod response fields are
+// appropriately changed.
+// checkResponseFields("hello");
 checkResponseFields("ismaster");
 checkResponseFields("isMaster");
diff --git a/jstests/replsets/ismaster1.js b/jstests/replsets/ismaster1.js
index f87f24cd41a..3cd6cb0a8dc 100644
--- a/jstests/replsets/ismaster1.js
+++ b/jstests/replsets/ismaster1.js
@@ -1,7 +1,6 @@
 /**
- * Checks all the easily testable fields in the response object returned by the hello() command and
- * its aliases, isMaster() and ismaster(). This test also checks that fields that should not be in
- * the document are absent.
+ * check all the easily testable fields in the document returned by the isMaster() command
+ * also checks that fields that should not be in the document are absent
  */
 
 // Skip db hash check because node 2 is slave delayed and may time out on awaitReplication.
@@ -29,36 +28,10 @@ var generateErrorString = function(badFields, missingFields, badValues, result)
     return str;
 };
 
-// This function calls checkResponseFields with the isMaster and hello commands.
-var runHelloCmdAndAliases = function(memberInfo) {
-    checkResponseFields(memberInfo, "ismaster");
-    checkResponseFields(memberInfo, "isMaster");
-    checkResponseFields(memberInfo, "hello");
-};
-
-// This function runs either the isMaster or hello command, and validates that the response is what
-// we expect.
-var checkResponseFields = function(memberInfo, cmd) {
-    // run the passed in command on the connection
-    var result = memberInfo.conn.getDB("admin").runCommand(cmd);
-    // If we are running the hello command, we must modify the expected fields. We expect
-    // "isWritablePrimary" and "secondaryDelaySecs" instead of "ismaster" and "slaveDelay" in the
-    // hello command response.
-    if (cmd === "hello") {
-        memberInfo.goodValues.isWritablePrimary = memberInfo.goodValues.ismaster;
-        delete memberInfo.goodValues.ismaster;
-        memberInfo.unwantedFields.push("ismaster");
-        memberInfo.unwantedFields =
-            memberInfo.unwantedFields.filter(f => f !== "isWritablePrimary");
-
-        if (memberInfo.goodValues.hasOwnProperty("slaveDelay")) {
-            memberInfo.goodValues.secondaryDelaySecs = memberInfo.goodValues.slaveDelay;
-            delete memberInfo.goodValues.slaveDelay;
-            memberInfo.unwantedFields.push("slaveDelay");
-            memberInfo.unwantedFields =
-                memberInfo.unwantedFields.filter(f => f !== "secondaryDelaySecs");
-        }
-    }
+// function to check a single result
+var checkMember = function(memberInfo) {
+    // run isMaster on the connection
+    result = memberInfo.conn.getDB("admin").runCommand({isMaster: 1});
 
     // make sure result doesn't contain anything it shouldn't
     var badFields = [];
@@ -105,7 +78,7 @@ var checkResponseFields = function(memberInfo, cmd) {
 };
 
 // start of test code
-var name = "hello_and_aliases";
+var name = "ismaster";
 var replTest = new ReplSetTest({name: name, nodes: 4});
 var nodes = replTest.startSet();
 
@@ -122,68 +95,54 @@ var agreeOnPrimaryAndSetVersion = function(setVersion) {
     print("Waiting for primary and replica set version " + setVersion);
 
     var nodes = replTest.nodes;
-    var currPrimary = undefined;
+    var primary = undefined;
     var lastSetVersion = setVersion;
     for (var i = 0; i < nodes.length; i++) {
         try {
-            var helloResult = nodes[i].getDB("admin").runCommand({hello: 1});
+            var isMasterResult = nodes[i].getDB("admin").runCommand({isMaster: 1});
         } catch (e) {
             // handle reconnect errors due to step downs
-            print("Error while calling hello on " + nodes[i] + ": " + e);
+            print("Error while calling isMaster on " + nodes[i] + ": " + e);
             return false;
         }
 
-        printjson(helloResult);
-        if (!currPrimary)
-            currPrimary = helloResult.primary;
+        printjson(isMasterResult);
+        if (!primary)
+            primary = isMasterResult.primary;
         if (!lastSetVersion)
-            lastSetVersion = helloResult.setVersion;
-        if (helloResult.primary != currPrimary || !currPrimary)
+            lastSetVersion = isMasterResult.setVersion;
+        if (isMasterResult.primary != primary || !primary)
             return false;
-        if (helloResult.setVersion != lastSetVersion)
+        if (isMasterResult.setVersion != lastSetVersion)
             return false;
     }
 
     return true;
 };
 
-var primary = replTest.getPrimary();
+var master = replTest.getPrimary();
 var expectedVersion = replTest.getReplSetConfigFromNode().version;
 assert.soon(function() {
     return agreeOnPrimaryAndSetVersion(expectedVersion);
 }, "Nodes did not initiate in less than a minute", 60000);
 
-// Check to see if the information from hello() and its aliases are correct at each node.
-// The checker only checks that the field exists when its value is "has".
-runHelloCmdAndAliases({
-    conn: primary,
-    name: "primary",
-    goodValues: {
-        setName: "hello_and_aliases",
-        setVersion: expectedVersion,
-        ismaster: true,
-        secondary: false,
-        ok: 1
-    },
+// check to see if the information from isMaster() is correct at each node
+// the checker only checks that the field exists when its value is "has"
+checkMember({
+    conn: master,
+    name: "master",
+    goodValues:
+        {setName: "ismaster", setVersion: expectedVersion, ismaster: true, secondary: false, ok: 1},
     wantedFields:
         ["hosts", "passives", "arbiters", "primary", "me", "maxBsonObjectSize", "localTime"],
-    unwantedFields: [
-        "isWritablePrimary",
-        "arbiterOnly",
-        "passive",
-        "slaveDelay",
-        "secondaryDelaySecs",
-        "hidden",
-        "tags",
-        "buildIndexes"
-    ]
+    unwantedFields: ["arbiterOnly", "passive", "slaveDelay", "hidden", "tags", "buildIndexes"]
 });
 
-runHelloCmdAndAliases({
+checkMember({
     conn: replTest._slaves[0],
-    name: "secondary",
+    name: "slave",
     goodValues: {
-        setName: "hello_and_aliases",
+        setName: "ismaster",
         setVersion: expectedVersion,
         ismaster: false,
         secondary: true,
@@ -192,22 +151,14 @@ runHelloCmdAndAliases({
     },
     wantedFields:
         ["hosts", "passives", "arbiters", "primary", "me", "maxBsonObjectSize", "localTime"],
-    unwantedFields: [
-        "isWritablePrimary",
-        "arbiterOnly",
-        "slaveDelay",
-        "secondaryDelaySecs",
-        "hidden",
-        "tags",
-        "buildIndexes"
-    ]
+    unwantedFields: ["arbiterOnly", "slaveDelay", "hidden", "tags", "buildIndexes"]
 });
 
-runHelloCmdAndAliases({
+checkMember({
     conn: replTest._slaves[1],
-    name: "delayed_secondary",
+    name: "delayed_slave",
     goodValues: {
-        setName: "hello_and_aliases",
+        setName: "ismaster",
         setVersion: expectedVersion,
         ismaster: false,
         secondary: true,
@@ -218,14 +169,14 @@ runHelloCmdAndAliases({
     },
     wantedFields:
         ["hosts", "passives", "arbiters", "primary", "me", "maxBsonObjectSize", "localTime"],
-    unwantedFields: ["isWritablePrimary", "arbiterOnly", "tags", "secondaryDelaySecs"]
+    unwantedFields: ["arbiterOnly", "tags"]
 });
 
-runHelloCmdAndAliases({
+checkMember({
     conn: replTest._slaves[2],
     name: "arbiter",
     goodValues: {
-        setName: "hello_and_aliases",
+        setName: "ismaster",
         setVersion: expectedVersion,
         ismaster: false,
         secondary: false,
@@ -234,19 +185,11 @@ runHelloCmdAndAliases({
     },
     wantedFields:
         ["hosts", "passives", "arbiters", "primary", "me", "maxBsonObjectSize", "localTime"],
-    unwantedFields: [
-        "isWritablePrimary",
-        "slaveDelay",
-        "secondaryDelaySecs",
-        "hidden",
-        "tags",
-        "buildIndexes",
-        "passive"
-    ]
+    unwantedFields: ["slaveDelay", "hidden", "tags", "buildIndexes", "passive"]
 });
 
-// Reconfigure the replset and make sure the changes are present on all members.
-config = primary.getDB("local").system.replset.findOne();
+// reconfigure and make sure the changes show up in ismaster on all members
+config = master.getDB("local").system.replset.findOne();
 config.version = config.version + 1;
 config.members[0].tags = {
     disk: "ssd"
@@ -260,23 +203,23 @@ config.members[2].tags = {
     disk: "hdd"
 };
 try {
-    result = primary.getDB("admin").runCommand({replSetReconfig: config});
+    result = master.getDB("admin").runCommand({replSetReconfig: config});
 } catch (e) {
     print(e);
 }
 
-primary = replTest.getPrimary();
+master = replTest.getPrimary();
 expectedVersion = config.version;
 assert.soon(function() {
     return agreeOnPrimaryAndSetVersion(expectedVersion);
 }, "Nodes did not sync in less than a minute", 60000);
 
 // check nodes for their new settings
-runHelloCmdAndAliases({
-    conn: primary,
-    name: "primary2",
+checkMember({
+    conn: master,
+    name: "master2",
     goodValues: {
-        setName: "hello_and_aliases",
+        setName: "ismaster",
         setVersion: expectedVersion,
         ismaster: true,
         secondary: false,
@@ -284,23 +227,14 @@ runHelloCmdAndAliases({
         ok: 1
     },
     wantedFields: ["hosts", "arbiters", "primary", "me", "maxBsonObjectSize", "localTime"],
-    unwantedFields: [
-        "isWritablePrimary",
-        "arbiterOnly",
-        "passives",
-        "passive",
-        "slaveDelay",
-        "secondaryDelaySecs",
-        "hidden",
-        "buildIndexes"
-    ]
+    unwantedFields: ["arbiterOnly", "passives", "passive", "slaveDelay", "hidden", "buildIndexes"]
 });
 
-runHelloCmdAndAliases({
+checkMember({
     conn: replTest._slaves[0],
-    name: "first_secondary",
+    name: "first_slave",
     goodValues: {
-        setName: "hello_and_aliases",
+        setName: "ismaster",
         setVersion: expectedVersion,
         ismaster: false,
         secondary: true,
@@ -310,21 +244,14 @@ runHelloCmdAndAliases({
         ok: 1
     },
     wantedFields: ["hosts", "arbiters", "primary", "me", "maxBsonObjectSize", "localTime"],
-    unwantedFields: [
-        "isWritablePrimary",
-        "arbiterOnly",
-        "passives",
-        "slaveDelay",
-        "secondaryDelaySecs",
-        "buildIndexes"
-    ]
+    unwantedFields: ["arbiterOnly", "passives", "slaveDelayed", "buildIndexes"]
 });
 
-runHelloCmdAndAliases({
+checkMember({
     conn: replTest._slaves[1],
-    name: "very_delayed_secondary",
+    name: "very_delayed_slave",
     goodValues: {
-        setName: "hello_and_aliases",
+        setName: "ismaster",
         setVersion: expectedVersion,
         ismaster: false,
         secondary: true,
@@ -336,14 +263,14 @@ runHelloCmdAndAliases({
         ok: 1
     },
     wantedFields: ["hosts", "arbiters", "primary", "me", "maxBsonObjectSize", "localTime"],
-    unwantedFields: ["isWritablePrimary", "arbiterOnly", "passives", "secondaryDelaySecs"]
+    unwantedFields: ["arbiterOnly", "passives"]
 });
 
-runHelloCmdAndAliases({
+checkMember({
     conn: replTest._slaves[2],
     name: "arbiter",
     goodValues: {
-        setName: "hello_and_aliases",
+        setName: "ismaster",
         setVersion: expectedVersion,
         ismaster: false,
         secondary: false,
@@ -351,20 +278,12 @@ runHelloCmdAndAliases({
         ok: 1
     },
     wantedFields: ["hosts", "arbiters", "primary", "me", "maxBsonObjectSize", "localTime"],
-    unwantedFields: [
-        "isWritablePrimary",
-        "slaveDelay",
-        "secondaryDelaySecs",
-        "hidden",
-        "tags",
-        "buildIndexes",
-        "passive"
-    ]
+    unwantedFields: ["slaveDelay", "hidden", "tags", "buildIndexes", "passive"]
 });
 
 // force reconfig and ensure all have the same setVersion afterwards
-config = primary.getDB("local").system.replset.findOne();
-primary.getDB("admin").runCommand({replSetReconfig: config, force: true});
+config = master.getDB("local").system.replset.findOne();
+master.getDB("admin").runCommand({replSetReconfig: config, force: true});
 
 assert.soon(function() {
     return agreeOnPrimaryAndSetVersion();
diff --git a/src/mongo/db/repl/is_master_response.cpp b/src/mongo/db/repl/is_master_response.cpp
index 96f7f465d9a..5d377768cc6 100644
--- a/src/mongo/db/repl/is_master_response.cpp
+++ b/src/mongo/db/repl/is_master_response.cpp
@@ -65,8 +65,6 @@ const std::string kLastWriteDateFieldName = "lastWriteDate";
 const std::string kLastMajorityWriteOpTimeFieldName = "majorityOpTime";
 const std::string kLastMajorityWriteDateFieldName = "majorityWriteDate";
 const std::string kLastWriteFieldName = "lastWrite";
-const std::string kIsWritablePrimaryFieldName = "isWritablePrimary";
-const std::string kSecondaryDelaySecsFieldName = "secondaryDelaySecs";
 
 // field name constants that don't directly correspond to member variables
 const std::string kInfoFieldName = "info";
@@ -104,7 +102,7 @@ IsMasterResponse::IsMasterResponse()
       _configSet(true),
       _shutdownInProgress(false) {}
 
-void IsMasterResponse::addToBSON(BSONObjBuilder* builder, bool useLegacyResponseFields) const {
+void IsMasterResponse::addToBSON(BSONObjBuilder* builder) const {
     if (_topologyVersion) {
         BSONObjBuilder topologyVersionBuilder(builder->subobjStart(kTopologyVersionFieldName));
         _topologyVersion->serialize(&topologyVersionBuilder);
@@ -143,11 +141,7 @@ void IsMasterResponse::addToBSON(BSONObjBuilder* builder, bool useLegacyResponse
     }
 
     if (!_configSet) {
-        if (useLegacyResponseFields) {
-            builder->append(kIsMasterFieldName, false);
-        } else {
-            builder->append(kIsWritablePrimaryFieldName, false);
-        }
+        builder->append(kIsMasterFieldName, false);
         builder->append(kSecondaryFieldName, false);
         builder->append(kInfoFieldName, "Does not have a valid replica set config");
         builder->append(kIsReplicaSetFieldName, true);
@@ -157,11 +151,7 @@ void IsMasterResponse::addToBSON(BSONObjBuilder* builder, bool useLegacyResponse
     invariant(_setVersionSet);
     builder->append(kSetVersionFieldName, static_cast<int>(_setVersion));
     invariant(_isMasterSet);
-    if (useLegacyResponseFields) {
-        builder->append(kIsMasterFieldName, _isMaster);
-    } else {
-        builder->append(kIsWritablePrimaryFieldName, _isMaster);
-    }
+    builder->append(kIsMasterFieldName, _isMaster);
     invariant(_isSecondarySet);
     builder->append(kSecondaryFieldName, _secondary);
 
@@ -175,14 +165,8 @@ void IsMasterResponse::addToBSON(BSONObjBuilder* builder, bool useLegacyResponse
         builder->append(kHiddenFieldName, _hidden);
     if (_buildIndexesSet)
         builder->append(kBuildIndexesFieldName, _buildIndexes);
-    if (_slaveDelaySet) {
-        if (useLegacyResponseFields) {
-            builder->appendIntOrLL(kSlaveDelayFieldName, durationCount<Seconds>(_slaveDelay));
-        } else {
-            builder->appendIntOrLL(kSecondaryDelaySecsFieldName,
-                                   durationCount<Seconds>(_slaveDelay));
-        }
-    }
+    if (_slaveDelaySet)
+        builder->appendIntOrLL(kSlaveDelayFieldName, durationCount<Seconds>(_slaveDelay));
     if (_tagsSet) {
         BSONObjBuilder tags(builder->subobjStart(kTagsFieldName));
         for (stdx::unordered_map<std::string, std::string>::const_iterator it = _tags.begin();
@@ -209,9 +193,9 @@ void IsMasterResponse::addToBSON(BSONObjBuilder* builder, bool useLegacyResponse
     }
 }
 
-BSONObj IsMasterResponse::toBSON(bool useLegacyResponseFields) const {
+BSONObj IsMasterResponse::toBSON() const {
     BSONObjBuilder builder;
-    addToBSON(&builder, useLegacyResponseFields);
+    addToBSON(&builder);
     return builder.obj();
 }
 
diff --git a/src/mongo/db/repl/is_master_response.h b/src/mongo/db/repl/is_master_response.h
index 9323c528db1..5ad203d45ee 100644
--- a/src/mongo/db/repl/is_master_response.h
+++ b/src/mongo/db/repl/is_master_response.h
@@ -62,21 +62,19 @@ public:
     Status initialize(const BSONObj& doc);
 
     /**
-     * Appends all non-default values to "builder". When true, "useLegacyResponseFields" indicates
-     * that we are responding to an isMaster command and not a hello command. Attach the legacy
-     * "ismaster" field if true, and the "isWritablePrimary" field otherwise. There are two values
-     * that are handled specially: if _inShutdown is true or _configSet is false, we will add a
-     * standard response to "builder" indicating either that we are in the middle of shutting down
-     * or we do not have a valid replica set config, ignoring the values of all other member
-     * variables.
+     * Appends all non-default values to "builder".
+     * There are two values that are handled specially: if _inShutdown is true or _configSet
+     * is false, we will add a standard response to "builder" indicating either that we are
+     * in the middle of shutting down or we do not have a valid replica set config, ignoring
+     * the values of all other member variables.
      */
-    void addToBSON(BSONObjBuilder* builder, bool useLegacyResponseFields) const;
+    void addToBSON(BSONObjBuilder* builder) const;
 
     /**
      * Returns a BSONObj consisting the results of calling addToBSON on an otherwise empty
      * BSONObjBuilder.
      */
-    BSONObj toBSON(bool useLegacyResponseFields = true) const;
+    BSONObj toBSON() const;
 
 
     // ===================== Accessors for member variables ================================= //
diff --git a/src/mongo/db/repl/replication_info.cpp b/src/mongo/db/repl/replication_info.cpp
index b5b57cd9432..8685a30ecb8 100644
--- a/src/mongo/db/repl/replication_info.cpp
+++ b/src/mongo/db/repl/replication_info.cpp
@@ -95,7 +95,6 @@ constexpr auto kLowerCaseIsMasterString = "ismaster"_sd;
 TopologyVersion appendReplicationInfo(OperationContext* opCtx,
                                       BSONObjBuilder& result,
                                       int level,
-                                      bool useLegacyResponseFields,
                                       boost::optional<TopologyVersion> clientTopologyVersion,
                                       boost::optional<long long> maxAwaitTimeMS) {
     TopologyVersion topologyVersion;
@@ -110,7 +109,7 @@ TopologyVersion appendReplicationInfo(OperationContext* opCtx,
         }
         auto isMasterResponse =
             replCoord->awaitIsMasterResponse(opCtx, horizonParams, clientTopologyVersion, deadline);
-        result.appendElements(isMasterResponse->toBSON(useLegacyResponseFields));
+        result.appendElements(isMasterResponse->toBSON());
         if (level) {
             replCoord->appendSlaveInfoData(&result);
         }
@@ -144,7 +143,7 @@ TopologyVersion appendReplicationInfo(OperationContext* opCtx,
         opCtx->sleepFor(Milliseconds(*maxAwaitTimeMS));
     }
 
-    result.appendBool((useLegacyResponseFields ? "ismaster" : "isWritablePrimary"),
+    result.appendBool("ismaster",
                       ReplicationCoordinator::get(opCtx)->isMasterForReportingPurposes());
 
     if (level) {
@@ -240,12 +239,9 @@ public:
         int level = configElement.numberInt();
 
         BSONObjBuilder result;
-        // TODO SERVER-50219: Change useLegacyResponseFields to false once the serverStatus changes
-        // to remove master-slave terminology are merged.
         appendReplicationInfo(opCtx,
                               result,
                               level,
-                              true /* useLegacyResponseFields */,
                               boost::none /* clientTopologyVersion */,
                               boost::none /* maxAwaitTimeMS */);
 
@@ -345,11 +341,6 @@ public:
             LastError::get(opCtx->getClient()).disable();
         }
 
-        // Parse the command name, which should be one of the following: hello, isMaster, or
-        // ismaster. If the command is "hello", we must attach an "isWritablePrimary" response field
-        // instead of "ismaster" and "secondaryDelaySecs" response field instead of "slaveDelay".
-        bool useLegacyResponseFields = (cmdObj.firstElementFieldNameStringData() != kHelloString);
-
         transport::Session::TagMask sessionTagsToSet = 0;
         transport::Session::TagMask sessionTagsToUnset = 0;
 
@@ -492,8 +483,8 @@ public:
         }
 
         auto result = replyBuilder->getBodyBuilder();
-        auto currentTopologyVersion = appendReplicationInfo(
-            opCtx, result, 0, useLegacyResponseFields, clientTopologyVersion, maxAwaitTimeMS);
+        auto currentTopologyVersion =
+            appendReplicationInfo(opCtx, result, 0, clientTopologyVersion, maxAwaitTimeMS);
 
         if (serverGlobalParams.clusterRole == ClusterRole::ConfigServer) {
             const int configServerModeNumber = 2;