SERVER-44475 Remove Query Knob

4 files changed, 26 insertions, 8 deletions

diff --git a/src/mongo/db/commands/SConscript b/src/mongo/db/commands/SConscript
index 3bdfb73e08d..1e1b927a553 100644
--- a/src/mongo/db/commands/SConscript
+++ b/src/mongo/db/commands/SConscript
@@ -520,6 +520,7 @@ env.Library(
         '$BUILD_DIR/mongo/db/db_raii',
         '$BUILD_DIR/mongo/db/index/index_access_methods',
         '$BUILD_DIR/mongo/db/pipeline/mongo_process_interface',
+        '$BUILD_DIR/mongo/db/pipeline/process_interface_factory_mongod',
         '$BUILD_DIR/mongo/db/query_exec',
         '$BUILD_DIR/mongo/db/query/map_reduce_output_format',
         '$BUILD_DIR/mongo/idl/idl_parser',
diff --git a/src/mongo/db/commands/map_reduce_command.cpp b/src/mongo/db/commands/map_reduce_command.cpp
index c605affd325..5cae9c1e228 100644
--- a/src/mongo/db/commands/map_reduce_command.cpp
+++ b/src/mongo/db/commands/map_reduce_command.cpp
@@ -78,11 +78,9 @@ private:
         // Execute the mapReduce as an aggregation pipeline only if fully upgraded to 4.4, since
         // a 4.2 mongos in a mixed version cluster expects a fundamentally different response that
         // is not supported by the aggregation equivalent.
-        if (internalQueryUseAggMapReduce.load() &&
-            serverGlobalParams.featureCompatibility.getVersion() ==
-                ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo44) {
+        if (serverGlobalParams.featureCompatibility.getVersion() ==
+            ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo44)
             return map_reduce_agg::runAggregationMapReduce(opCtx, cmd, result, boost::none);
-        }
         return mr::runMapReduce(opCtx, dbname, cmd, errmsg, result);
     }
 } mapReduceCommand;
diff --git a/src/mongo/db/commands/map_reduce_command_base.h b/src/mongo/db/commands/map_reduce_command_base.h
index 5166cdec327..1595242b4b4 100644
--- a/src/mongo/db/commands/map_reduce_command_base.h
+++ b/src/mongo/db/commands/map_reduce_command_base.h
@@ -44,6 +44,24 @@ public:
                "details.";
     }
 
+    /**
+     * The mapReduce command supports only 'local' and 'available' readConcern levels.
+     * For aggregation-based mapReduce there are no known restrictions to broader support, but work
+     * would need to be done confirm support for both command and aggregation stages as is done for
+     * the aggregate command.
+     */
+    virtual ReadConcernSupportResult supportsReadConcern(const BSONObj& cmdObj,
+                                                         repl::ReadConcernLevel level) const {
+        static const Status kReadConcernNotSupported{ErrorCodes::InvalidOptions,
+                                                     "read concern not supported"};
+        static const Status kDefaultReadConcernNotPermitted{ErrorCodes::InvalidOptions,
+                                                            "default read concern not permitted"};
+        return {{level != repl::ReadConcernLevel::kLocalReadConcern &&
+                     level != repl::ReadConcernLevel::kAvailableReadConcern,
+                 kReadConcernNotSupported},
+                {kDefaultReadConcernNotPermitted}};
+    }
+
     virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
         return map_reduce_common::mrSupportsWriteConcern(cmd);
     }
@@ -74,9 +92,8 @@ public:
                    const OpMsgRequest& request,
                    ExplainOptions::Verbosity verbosity,
                    rpc::ReplyBuilderInterface* result) const override {
-        if (internalQueryUseAggMapReduce.load() &&
-            serverGlobalParams.featureCompatibility.getVersion() ==
-                ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo44) {
+        if (serverGlobalParams.featureCompatibility.getVersion() ==
+            ServerGlobalParams::FeatureCompatibility::Version::kFullyUpgradedTo44) {
             auto builder = result->getBodyBuilder();
             auto explain = boost::make_optional(verbosity);
             try {
diff --git a/src/mongo/db/commands/mr_test.cpp b/src/mongo/db/commands/mr_test.cpp
index c65f492893d..f7a05c77103 100644
--- a/src/mongo/db/commands/mr_test.cpp
+++ b/src/mongo/db/commands/mr_test.cpp
@@ -341,7 +341,9 @@ void MapReduceOpObserver::onStartIndexBuild(OperationContext* opCtx,
                                             const UUID& indexBuildUUID,
                                             const std::vector<BSONObj>& indexes,
                                             bool fromMigrate) {
-    indexesCreated = indexes;
+    for (auto&& obj : indexes) {
+        indexesCreated.push_back(obj.getOwned());
+    }
 }
 
 void MapReduceOpObserver::onInserts(OperationContext* opCtx,