SERVER-49060: updating generic FCV constants

jstests/sharding/database_versioning_all_commands.js

@@ -664,7 +664,7 @@ let testCases = {
     whatsmyuri: {skip: "executes locally on mongos (not sent to any remote node)"},
 };
 
-commandsRemovedFromMongosIn46.forEach(function(cmd) {
+commandsRemovedFromMongosSinceLastLTS.forEach(function(cmd) {
     testCases[cmd] = {skip: "must define test coverage for 4.6 backwards compatibility"};
 });
 
@@ -688,14 +688,15 @@ assert.commandWorked(listCommandsRes);
     // After iterating through all the existing commands, ensure there were no additional test cases
     // that did not correspond to any mongos command.
     for (let key of Object.keys(testCases)) {
-        // We have defined real test cases for commands added in 4.6 so that the test cases are
-        // exercised in the regular suites, but because these test cases can't run in the last
-        // stable suite, we skip processing them here to avoid failing the below assertion.
-        // We have defined "skip" test cases for commands removed in 4.6 so the test case is defined
-        // in last stable suites (in which these commands still exist on the mongos), but these test
-        // cases won't be run in regular suites, so we skip processing them below as well.
-        if (commandsAddedToMongosIn46.includes(key) ||
-            commandsRemovedFromMongosIn46.includes(key)) {
+        // We have defined real test cases for commands added since the last LTS version so that the
+        // test cases are exercised in the regular suites, but because these test cases can't run in
+        // the last stable suite, we skip processing them here to avoid failing the below assertion.
+        // We have defined "skip" test cases for commands removed since the last LTS version so the
+        // test case is defined in last stable suites (in which these commands still exist on the
+        // mongos), but these test cases won't be run in regular suites, so we skip processing them
+        // below as well.
+        if (commandsAddedToMongosSinceLastLTS.includes(key) ||
+            commandsRemovedFromMongosSinceLastLTS.includes(key)) {
             continue;
         }
         assert(testCases[key].validated || testCases[key].conditional,

jstests/sharding/libs/last_stable_mongod_commands.js

@@ -1,9 +1,10 @@
-// These commands were removed from mongod in 4.6, but will still appear in the listCommands output
-// of a 4.4 mongod. To increase test coverage and allow us to run on same- and
-// mixed-version suites, we allow these commands to have a test defined without always existing on
-// the servers being used.
-const commandsRemovedFromMongodIn46 = ["_configsvrCreateCollection", "mapreduce.shardedfinish"];
-// These commands were added in mongod 4.6, so will not appear in the listCommands output of a
-// 4.4 mongod. We will allow these commands to have a test defined without always existing on the
-// mongod being used.
-const commandsAddedToMongodIn46 = [];
+// These commands were removed from mongod since the last LTS version, but will still appear in the
+// listCommands output of a last LTS version mongod. To increase test coverage and allow us
+// to run on same- and mixed-version suites, we allow these commands to have a test defined without
+// always existing on the servers being used.
+const commandsRemovedFromMongodSinceLastLTS =
+    ["_configsvrCreateCollection", "mapreduce.shardedfinish"];
+// These commands were added in mongod since the last LTS version, so will not appear in the
+// listCommands output of a last LTS version mongod. We will allow these commands to have a
+// test defined without always existing on the mongod being used.
+const commandsAddedToMongodSinceLastLTS = [];

jstests/sharding/libs/last_stable_mongos_commands.js

@@ -1,10 +1,10 @@
-// These commands were removed from mongos 4.6, but will still appear in the listCommands output
-// of a 4.4 mongos. A last-stable mongos will be unable to run a command on a latest version shard
-// that no longer supports that command. To increase test coverage and allow us to run on same- and
-// mixed-version suites, we allow these commands to have a test defined without always existing on
-// the servers being used.
-const commandsRemovedFromMongosIn46 = [];
-// These commands were added in mongos 4.6, so will not appear in the listCommands output of a
-// 4.4 mongos. We will allow these commands to have a test defined without always existing on the
-// mongos being used.
-const commandsAddedToMongosIn46 = ["reshardCollection"];
+// These commands were removed from mongos since the last LTS version, but will still appear in the
+// listCommands output of a last LTS version mongos. A last-stable mongos will be unable to
+// run a command on a latest version shard that no longer supports that command. To increase test
+// coverage and allow us to run on same- and mixed-version suites, we allow these commands to have a
+// test defined without always existing on the servers being used.
+const commandsRemovedFromMongosSinceLastLTS = [];
+// These commands were added in mongos since the last LTS version, so will not appear in the
+// listCommands output of a last LTS version mongos. We will allow these commands to have a test
+// defined without always existing on the mongos being used.
+const commandsAddedToMongosSinceLastLTS = ["reshardCollection"];

jstests/sharding/read_write_concern_defaults_application.js

@@ -654,7 +654,7 @@ let testCases = {
     whatsmyuri: {skip: "internal command"},
 };
 
-commandsRemovedFromMongodIn46.forEach(function(cmd) {
+commandsRemovedFromMongodSinceLastLTS.forEach(function(cmd) {
     testCases[cmd] = {skip: "must define test coverage for 4.4 backwards compatibility"};
 });
 

jstests/sharding/safe_secondary_reads_drop_recreate.js

@@ -308,7 +308,7 @@ let testCases = {
     whatsmyuri: {skip: "does not return user data"}
 };
 
-commandsRemovedFromMongosIn46.forEach(function(cmd) {
+commandsRemovedFromMongosSinceLastLTS.forEach(function(cmd) {
     testCases[cmd] = {skip: "must define test coverage for 4.4 backwards compatibility"};
 });
 

jstests/sharding/safe_secondary_reads_single_migration_suspend_range_deletion.js

@@ -380,7 +380,7 @@ let testCases = {
     whatsmyuri: {skip: "does not return user data"}
 };
 
-commandsRemovedFromMongosIn46.forEach(function(cmd) {
+commandsRemovedFromMongosSinceLastLTS.forEach(function(cmd) {
     testCases[cmd] = {skip: "must define test coverage for 4.4 backwards compatibility"};
 });
 

jstests/sharding/safe_secondary_reads_single_migration_waitForDelete.js

@@ -315,7 +315,7 @@ let testCases = {
     whatsmyuri: {skip: "does not return user data"}
 };
 
-commandsRemovedFromMongosIn46.forEach(function(cmd) {
+commandsRemovedFromMongosSinceLastLTS.forEach(function(cmd) {
     testCases[cmd] = {skip: "must define test coverage for 4.4 backwards compatibility"};
 });
 

src/mongo/db/catalog/coll_mod.cpp

@@ -203,14 +203,13 @@ StatusWith<CollModRequest> parseCollModRequest(OperationContext* opCtx,
             // Save this to a variable to avoid reading the atomic variable multiple times.
             const auto currentFCV = serverGlobalParams.featureCompatibility.getVersion();
 
-            // If the feature compatibility version is not 4.6, and we are validating features as
-            // master, ban the use of new agg features introduced in 4.6 to prevent them from being
-            // persisted in the catalog.
+            // If the feature compatibility version is not kLatest, and we are validating features
+            // as master, ban the use of new agg features introduced in kLatest to prevent them from
+            // being persisted in the catalog.
             boost::optional<ServerGlobalParams::FeatureCompatibility::Version>
                 maxFeatureCompatibilityVersion;
             if (serverGlobalParams.validateFeaturesAsMaster.load() &&
-                currentFCV !=
-                    ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46) {
+                currentFCV != ServerGlobalParams::FeatureCompatibility::kLatest) {
                 maxFeatureCompatibilityVersion = currentFCV;
             }
             cmr.collValidator = coll->parseValidator(opCtx,

src/mongo/db/catalog/database_impl.cpp

@@ -842,11 +842,11 @@ Status DatabaseImpl::userCreateNS(OperationContext* opCtx,
         // Save this to a variable to avoid reading the atomic variable multiple times.
         const auto currentFCV = serverGlobalParams.featureCompatibility.getVersion();
 
-        // If the feature compatibility version is not 4.6, and we are validating features as
-        // master, ban the use of new agg features introduced in 4.6 to prevent them from being
+        // If the feature compatibility version is not kLatest, and we are validating features as
+        // master, ban the use of new agg features introduced in kLatest to prevent them from being
         // persisted in the catalog.
         if (serverGlobalParams.validateFeaturesAsMaster.load() &&
-            currentFCV != ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46) {
+            currentFCV != ServerGlobalParams::FeatureCompatibility::kLatest) {
             expCtx->maxFeatureCompatibilityVersion = currentFCV;
         }
 

src/mongo/db/commands/feature_compatibility_version.cpp

@@ -175,13 +175,13 @@ void FeatureCompatibilityVersion::updateMinWireVersion() {
     WireSpec& spec = WireSpec::instance();
 
     switch (serverGlobalParams.featureCompatibility.getVersion()) {
-        case ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46:
+        case ServerGlobalParams::FeatureCompatibility::kLatest:
         case ServerGlobalParams::FeatureCompatibility::Version::kUpgradingTo46:
         case ServerGlobalParams::FeatureCompatibility::Version::kDowngradingTo44:
             spec.incomingInternalClient.minWireVersion = LATEST_WIRE_VERSION;
             spec.outgoing.minWireVersion = LATEST_WIRE_VERSION;
             return;
-        case ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo44:
+        case ServerGlobalParams::FeatureCompatibility::kLastLTS:
             spec.incomingInternalClient.minWireVersion = LATEST_WIRE_VERSION - 1;
             spec.outgoing.minWireVersion = LATEST_WIRE_VERSION - 1;
             return;
@@ -196,7 +196,7 @@ void FeatureCompatibilityVersion::_setVersion(
     serverGlobalParams.featureCompatibility.setVersion(newVersion);
     updateMinWireVersion();
 
-    if (newVersion != ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo44) {
+    if (newVersion != ServerGlobalParams::FeatureCompatibility::kLastLTS) {
         // Close all incoming connections from internal clients with binary versions lower than
         // ours.
         opCtx->getServiceContext()->getServiceEntryPoint()->endAllSessions(
@@ -207,7 +207,7 @@ void FeatureCompatibilityVersion::_setVersion(
             .dropConnections(transport::Session::kKeepOpen);
     }
 
-    if (newVersion != ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46) {
+    if (newVersion != ServerGlobalParams::FeatureCompatibility::kLatest) {
         if (MONGO_unlikely(hangBeforeAbortingRunningTransactionsOnFCVDowngrade.shouldFail())) {
             LOGV2(20460,
                   "FeatureCompatibilityVersion - "
@@ -228,7 +228,7 @@ void FeatureCompatibilityVersion::_setVersion(
     // 1. Setting featureCompatibilityVersion from downgrading to fullyDowngraded.
     // 2. Setting featureCompatibilityVersion from fullyDowngraded to upgrading.
     const auto shouldIncrementTopologyVersion =
-        newVersion == ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo44 ||
+        newVersion == ServerGlobalParams::FeatureCompatibility::kLastLTS ||
         newVersion == ServerGlobalParams::FeatureCompatibility::Version::kUpgradingTo46;
     if (isReplSet && shouldIncrementTopologyVersion) {
         replCoordinator->incrementTopologyVersion();
@@ -317,7 +317,7 @@ void FeatureCompatibilityVersionParameter::append(OperationContext* opCtx,
 
     BSONObjBuilder featureCompatibilityVersionBuilder(b.subobjStart(name));
     switch (serverGlobalParams.featureCompatibility.getVersion()) {
-        case ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46:
+        case ServerGlobalParams::FeatureCompatibility::kLatest:
             featureCompatibilityVersionBuilder.append(
                 FeatureCompatibilityVersionParser::kVersionField,
                 FeatureCompatibilityVersionParser::kVersion46);
@@ -338,7 +338,7 @@ void FeatureCompatibilityVersionParameter::append(OperationContext* opCtx,
                 FeatureCompatibilityVersionParser::kTargetVersionField,
                 FeatureCompatibilityVersionParser::kVersion44);
             return;
-        case ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo44:
+        case ServerGlobalParams::FeatureCompatibility::kLastLTS:
             featureCompatibilityVersionBuilder.append(
                 FeatureCompatibilityVersionParser::kVersionField,
                 FeatureCompatibilityVersionParser::kVersion44);

src/mongo/db/repl/initial_syncer.cpp

@@ -1087,8 +1087,8 @@ void InitialSyncer::_fcvFetcherCallback(const StatusWith<Fetcher::QueryResponse>
     auto version = fCVParseSW.getValue();
 
     // Changing the featureCompatibilityVersion during initial sync is unsafe.
-    if (version > ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo44 &&
-        version < ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46) {
+    if (version > ServerGlobalParams::FeatureCompatibility::kLastLTS &&
+        version < ServerGlobalParams::FeatureCompatibility::kLatest) {
         onCompletionGuard->setResultAndCancelRemainingWork_inlock(
             lock,
             Status(ErrorCodes::IncompatibleServerVersion,

src/mongo/db/repl/oplog_applier_impl_test_fixture.cpp

@@ -127,7 +127,7 @@ void OplogApplierImplTest::setUp() {
     // test fixture does not create a featureCompatibilityVersion document from which to initialize
     // the server parameter.
     serverGlobalParams.featureCompatibility.setVersion(
-        ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46);
+        ServerGlobalParams::FeatureCompatibility::kLatest);
 
     // This is necessary to generate ghost timestamps for index builds that are not 0, since 0 is an
     // invalid timestamp.

src/mongo/db/s/config/sharding_catalog_manager_shard_operations.cpp

@@ -339,14 +339,15 @@ StatusWith<ShardType> ShardingCatalogManager::_validateHostAsShard(
                                                 << connectionString.toString() << " as a shard");
     }
     if (serverGlobalParams.featureCompatibility.getVersion() >
-        ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo44) {
-        // If the cluster's FCV is 4.6, or upgrading to / downgrading from, the node being added
-        // must be a v4.6 binary.
+        ServerGlobalParams::FeatureCompatibility::kLastLTS) {
+        // If the cluster's FCV is kLatest, or upgrading to / downgrading from, the node being added
+        // must be a version kLatest binary.
         invariant(maxWireVersion == WireVersion::LATEST_WIRE_VERSION);
     } else {
-        // If the cluster's FCV is 4.4, the node being added must be a v4.4 or v4.6 binary.
+        // If the cluster's FCV is kLastLTS, the node being added must be a version kLastLTS or
+        // version kLatest binary.
         invariant(serverGlobalParams.featureCompatibility.getVersion() ==
-                  ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo44);
+                  ServerGlobalParams::FeatureCompatibility::kLastLTS);
         invariant(maxWireVersion >= WireVersion::LATEST_WIRE_VERSION - 1);
     }
 
@@ -651,7 +652,7 @@ StatusWith<std::string> ShardingCatalogManager::addShard(
 
         BSONObj setFCVCmd;
         switch (serverGlobalParams.featureCompatibility.getVersion()) {
-            case ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46:
+            case ServerGlobalParams::FeatureCompatibility::kLatest:
             case ServerGlobalParams::FeatureCompatibility::Version::kUpgradingTo46:
                 setFCVCmd = BSON(FeatureCompatibilityVersionCommandParser::kCommandName
                                  << FeatureCompatibilityVersionParser::kVersion46

src/mongo/db/s/sharding_mongod_test_fixture.cpp

@@ -138,7 +138,7 @@ ShardingMongodTestFixture::ShardingMongodTestFixture() {
     // Set the highest FCV because otherwise it defaults to the lower FCV. This way we default to
     // testing this release's code, not backwards compatibility code.
     serverGlobalParams.featureCompatibility.setVersion(
-        ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46);
+        ServerGlobalParams::FeatureCompatibility::kLatest);
 }
 
 ShardingMongodTestFixture::~ShardingMongodTestFixture() = default;

src/mongo/db/server_options.h

@@ -198,6 +198,10 @@ struct ServerGlobalParams {
             kFullyUpgradedTo46 = 4,
         };
 
+        static constexpr Version kLatest = Version::kFullyUpgradedTo46;
+        static constexpr Version kLastContinuous = Version::kFullyDowngradedTo44;
+        static constexpr Version kLastLTS = Version::kFullyDowngradedTo44;
+
         /**
          * On startup, the featureCompatibilityVersion may not have been explicitly set yet. This
          * exposes the actual state of the featureCompatibilityVersion if it is uninitialized.

src/mongo/db/views/view_catalog.cpp

@@ -331,11 +331,11 @@ StatusWith<stdx::unordered_set<NamespaceString>> ViewCatalog::_validatePipeline(
     // Save this to a variable to avoid reading the atomic variable multiple times.
     auto currentFCV = serverGlobalParams.featureCompatibility.getVersion();
 
-    // If the feature compatibility version is not 4.6, and we are validating features as master,
-    // ban the use of new agg features introduced in 4.6 to prevent them from being persisted in the
-    // catalog.
+    // If the feature compatibility version is not kLatest, and we are validating features as
+    // master, ban the use of new agg features introduced in kLatest to prevent them from being
+    // persisted in the catalog.
     if (serverGlobalParams.validateFeaturesAsMaster.load() &&
-        currentFCV != ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46) {
+        currentFCV != ServerGlobalParams::FeatureCompatibility::kLatest) {
         expCtx->maxFeatureCompatibilityVersion = currentFCV;
     }
 

src/mongo/dbtests/dbtests.cpp

@@ -180,7 +180,7 @@ int dbtestsMain(int argc, char** argv) {
 
     mongo::runGlobalInitializersOrDie(std::vector<std::string>(argv, argv + argc));
     serverGlobalParams.featureCompatibility.setVersion(
-        ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46);
+        ServerGlobalParams::FeatureCompatibility::kLatest);
     repl::ReplSettings replSettings;
     replSettings.setOplogSizeBytes(10 * 1024 * 1024);
     setGlobalServiceContext(ServiceContext::make());

src/mongo/s/mongos_main.cpp

@@ -904,7 +904,7 @@ MONGO_INITIALIZER_WITH_PREREQUISITES(SetFeatureCompatibilityVersionLatest,
                                      ("EndStartupOptionStorage"))
 (InitializerContext* context) {
     serverGlobalParams.featureCompatibility.setVersion(
-        ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46);
+        ServerGlobalParams::FeatureCompatibility::kLatest);
     return Status::OK();
 }
 

src/mongo/shell/mongo_main.cpp

@@ -120,7 +120,7 @@ MONGO_INITIALIZER_WITH_PREREQUISITES(SetFeatureCompatibilityVersionLatest,
                                      ("EndStartupOptionSetup"))
 (InitializerContext* context) {
     mongo::serverGlobalParams.featureCompatibility.setVersion(
-        ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46);
+        ServerGlobalParams::FeatureCompatibility::kLatest);
     return Status::OK();
 }
 

src/mongo/unittest/unittest.cpp

@@ -157,7 +157,7 @@ namespace {
 // with a meaningful value will trigger failures as of SERVER-32630.
 void setUpFCV() {
     serverGlobalParams.featureCompatibility.setVersion(
-        ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo46);
+        ServerGlobalParams::FeatureCompatibility::kLatest);
 }
 void tearDownFCV() {
     serverGlobalParams.featureCompatibility.reset();