SERVER-44884 Remove the 'useNewUpsert' flag after branching for 4.5

8 files changed, 7 insertions, 54 deletions

diff --git a/src/mongo/db/pipeline/aggregation_request.cpp b/src/mongo/db/pipeline/aggregation_request.cpp
index f5c417e30e9..34128ff6b0e 100644
--- a/src/mongo/db/pipeline/aggregation_request.cpp
+++ b/src/mongo/db/pipeline/aggregation_request.cpp
@@ -212,16 +212,11 @@ StatusWith<AggregationRequest> AggregationRequest::parseFromBSON(
             }
 
             request.setUse44SortKeys(elem.boolean());
-        } else if (fieldName == kUseNewUpsert) {
-            // TODO SERVER-44884: After branching for 4.5, we will continue to accept this option
-            // for upgrade purposes but will ignore it, as any supported version will be capable of
-            // using the new upsert mechanism. In 4.7 we will completely remove this parameter.
-            if (elem.type() != BSONType::Bool) {
-                return {ErrorCodes::TypeMismatch,
-                        str::stream() << kUseNewUpsert << " must be a boolean, not a "
-                                      << typeName(elem.type())};
-            }
-            request.setUseNewUpsert(elem.boolean());
+        } else if (fieldName == "useNewUpsert"_sd) {
+            // TODO SERVER-46751: we must retain the ability to ingest the 'useNewUpsert' field for
+            // 4.6 upgrade purposes, since a 4.4 mongoS will always send {useNewUpsert:true} to the
+            // shards. We do nothing with it because useNewUpsert will be automatically used in 4.6
+            // when appropriate. Remove this final vestige of useNewUpsert during the 4.7 dev cycle.
         } else if (fieldName == kIsMapReduceCommand) {
             if (elem.type() != BSONType::Bool) {
                 return {ErrorCodes::TypeMismatch,
@@ -328,7 +323,6 @@ Document AggregationRequest::serializeToCommandObj() const {
         // Only serialize runtime constants if any were specified.
         {kRuntimeConstants, _runtimeConstants ? Value(_runtimeConstants->toBSON()) : Value()},
         {kUse44SortKeys, _use44SortKeys ? Value(true) : Value()},
-        {kUseNewUpsert, _useNewUpsert ? Value(true) : Value()},
         {kIsMapReduceCommand, _isMapReduceCommand ? Value(true) : Value()},
     };
 }
diff --git a/src/mongo/db/pipeline/aggregation_request.h b/src/mongo/db/pipeline/aggregation_request.h
index eb2594e7765..c6f2b2aee40 100644
--- a/src/mongo/db/pipeline/aggregation_request.h
+++ b/src/mongo/db/pipeline/aggregation_request.h
@@ -64,7 +64,6 @@ public:
     static constexpr StringData kExchangeName = "exchange"_sd;
     static constexpr StringData kRuntimeConstants = "runtimeConstants"_sd;
     static constexpr StringData kUse44SortKeys = "use44SortKeys"_sd;
-    static constexpr StringData kUseNewUpsert = "useNewUpsert"_sd;
     static constexpr StringData kIsMapReduceCommand = "isMapReduceCommand"_sd;
 
     static constexpr long long kDefaultBatchSize = 101;
@@ -223,10 +222,6 @@ public:
         return _use44SortKeys;
     }
 
-    bool getUseNewUpsert() const {
-        return _useNewUpsert;
-    }
-
     bool getIsMapReduceCommand() const {
         return _isMapReduceCommand;
     }
@@ -299,10 +294,6 @@ public:
         _use44SortKeys = use44SortKeys;
     }
 
-    void setUseNewUpsert(bool useNewUpsert) {
-        _useNewUpsert = useNewUpsert;
-    }
-
     void setIsMapReduceCommand(bool isMapReduce) {
         _isMapReduceCommand = isMapReduce;
     }
@@ -361,10 +352,6 @@ private:
     // use the updated sort key format when returning change stream results.
     bool _use44SortKeys = false;
 
-    // Indicates whether the aggregation may use the new 'upsertSupplied' mechanism when running
-    // $merge stages. All 4.4 mongoS and some versions of 4.2 set this flag.
-    bool _useNewUpsert = false;
-
     // True when an aggregation was invoked by the MapReduce command.
     bool _isMapReduceCommand = false;
 };
diff --git a/src/mongo/db/pipeline/expression_context.cpp b/src/mongo/db/pipeline/expression_context.cpp
index 4e203f16d38..0c6f80e8b82 100644
--- a/src/mongo/db/pipeline/expression_context.cpp
+++ b/src/mongo/db/pipeline/expression_context.cpp
@@ -64,11 +64,6 @@ ExpressionContext::ExpressionContext(OperationContext* opCtx,
                         std::move(processInterface),
                         std::move(resolvedNamespaces),
                         std::move(collUUID)) {
-    // Any request which did not originate from a mongoS, or which did originate from a mongoS but
-    // has the 'useNewUpsert' flag set, can use the new upsertSupplied mechanism for $merge.
-    // TODO SERVER-44884: Remove this flag after we branch for 4.5.
-    useNewUpsert = request.getUseNewUpsert() || !request.isFromMongos();
-
     if (request.getIsMapReduceCommand()) {
         // mapReduce command JavaScript invocation is only subject to the server global
         // 'jsHeapLimitMB' limit.
@@ -117,12 +112,6 @@ ExpressionContext::ExpressionContext(
     if (!isMapReduce) {
         jsHeapLimitMB = internalQueryJavaScriptHeapSizeLimitMB.load();
     }
-
-    // Any request which did not originate from a mongoS can use the new upsertSupplied mechanism.
-    // This is used to set 'useNewUpsert' when constructing a MR context on mongoS or mongoD. The MR
-    // on mongoS will be issued as an aggregation to the shards and will use the other constructor.
-    // TODO SERVER-44884: Remove this flag after we branch for 4.5.
-    useNewUpsert = !fromMongos;
 }
 
 ExpressionContext::ExpressionContext(OperationContext* opCtx,
@@ -199,7 +188,6 @@ intrusive_ptr<ExpressionContext> ExpressionContext::copyWith(
     expCtx->maxFeatureCompatibilityVersion = maxFeatureCompatibilityVersion;
     expCtx->subPipelineDepth = subPipelineDepth;
     expCtx->tempDir = tempDir;
-    expCtx->useNewUpsert = useNewUpsert;
     expCtx->jsHeapLimitMB = jsHeapLimitMB;
 
     expCtx->variables = variables;
diff --git a/src/mongo/db/pipeline/expression_context.h b/src/mongo/db/pipeline/expression_context.h
index 35be79e3b1a..de9442dd6b3 100644
--- a/src/mongo/db/pipeline/expression_context.h
+++ b/src/mongo/db/pipeline/expression_context.h
@@ -352,11 +352,6 @@ public:
     // other than the "k44SortKey" format, so this will be removed.
     SortKeyFormat sortKeyFormat = SortKeyFormat::k44SortKey;
 
-    // True if this context is associated with a pipeline which is permitted to use the new
-    // upsertSupplied mechanism for applicable $merge modes.
-    // TODO SERVER-44884: remove this when we branch for 4.5.
-    bool useNewUpsert = false;
-
     // True if this ExpressionContext is used to parse a view definition pipeline.
     bool isParsingViewDefinition = false;
 
diff --git a/src/mongo/db/pipeline/process_interface/common_mongod_process_interface.cpp b/src/mongo/db/pipeline/process_interface/common_mongod_process_interface.cpp
index e8004eede08..197bc5fcfd2 100644
--- a/src/mongo/db/pipeline/process_interface/common_mongod_process_interface.cpp
+++ b/src/mongo/db/pipeline/process_interface/common_mongod_process_interface.cpp
@@ -598,9 +598,8 @@ Update CommonMongodProcessInterface::buildUpdateOp(
                 entry.setU(std::move(u));
                 entry.setC(std::move(c));
                 entry.setUpsert(upsert != UpsertType::kNone);
-                // TODO SERVER-44884: after branching for 4.5, remove the 'useNewUpsert' flag.
-                entry.setUpsertSupplied({{entry.getUpsert() && expCtx->useNewUpsert,
-                                          upsert == UpsertType::kInsertSuppliedDoc}});
+                entry.setUpsertSupplied(
+                    {{entry.getUpsert(), upsert == UpsertType::kInsertSuppliedDoc}});
                 entry.setMulti(multi);
                 return entry;
             }());
diff --git a/src/mongo/db/pipeline/sharded_agg_helpers.cpp b/src/mongo/db/pipeline/sharded_agg_helpers.cpp
index eeb614813ef..695a94f7409 100644
--- a/src/mongo/db/pipeline/sharded_agg_helpers.cpp
+++ b/src/mongo/db/pipeline/sharded_agg_helpers.cpp
@@ -157,10 +157,6 @@ BSONObj genericTransformForShards(MutableDocument&& cmdForShards,
         // there will only be one sort key format for changes streams, so there will be no need to
         // set this flag anymore. This flag has no effect on pipelines without a change stream.
         cmdForShards[AggregationRequest::kUse44SortKeys] = Value(true);
-        // TODO SERVER-44884: We set this flag to indicate that the shards should always use the new
-        // upsert mechanism when executing relevant $merge modes. After branching for 4.5, supported
-        // upgrade versions will all use the new mechanism, and we can remove this flag.
-        cmdForShards[AggregationRequest::kUseNewUpsert] = Value(true);
     }
 
     return cmdForShards.freeze().toBson();
diff --git a/src/mongo/db/views/resolved_view.cpp b/src/mongo/db/views/resolved_view.cpp
index ff4442dc85e..a8a1c9cf4a5 100644
--- a/src/mongo/db/views/resolved_view.cpp
+++ b/src/mongo/db/views/resolved_view.cpp
@@ -111,7 +111,6 @@ AggregationRequest ResolvedView::asExpandedViewAggregation(
     expandedRequest.setUnwrappedReadPref(request.getUnwrappedReadPref());
     expandedRequest.setBypassDocumentValidation(request.shouldBypassDocumentValidation());
     expandedRequest.setAllowDiskUse(request.shouldAllowDiskUse());
-    expandedRequest.setUseNewUpsert(request.getUseNewUpsert());
     expandedRequest.setIsMapReduceCommand(request.getIsMapReduceCommand());
 
     // Operations on a view must always use the default collation of the view. We must have already
diff --git a/src/mongo/s/commands/cluster_map_reduce_agg.cpp b/src/mongo/s/commands/cluster_map_reduce_agg.cpp
index 0f0c18bde35..6c6365500f4 100644
--- a/src/mongo/s/commands/cluster_map_reduce_agg.cpp
+++ b/src/mongo/s/commands/cluster_map_reduce_agg.cpp
@@ -128,11 +128,6 @@ Document serializeToCommand(BSONObj originalCmd, const MapReduce& parsedMr, Pipe
             Value(originalCmd[AggregationRequest::kCollationName]);
     }
 
-    // TODO SERVER-44884: We set this flag to indicate that the shards should always use the new
-    // upsert mechanism when executing relevant $merge modes. After branching for 4.5, supported
-    // upgrade versions will all use the new mechanism, and we can remove this flag.
-    translatedCmd[AggregationRequest::kUseNewUpsert] = Value(true);
-
     // Append generic command options.
     for (const auto& elem : CommandHelpers::appendPassthroughFields(originalCmd, BSONObj())) {
         translatedCmd[elem.fieldNameStringData()] = Value(elem);