SERVER-39066 Add OpObservers and oplog handling for startIndexBuild and commitIndexBuild

18 files changed, 556 insertions, 0 deletions

diff --git a/src/mongo/db/SConscript b/src/mongo/db/SConscript
index aa53f6d31d7..b3c8b2ab9a4 100644
--- a/src/mongo/db/SConscript
+++ b/src/mongo/db/SConscript
@@ -986,6 +986,7 @@ env.Library(
     LIBDEPS=[
         'db_raii',
         'index/index_access_methods',
+        '$BUILD_DIR/mongo/db/index_builds_coordinator_interface',
         '$BUILD_DIR/mongo/db/catalog/index_catalog',
         '$BUILD_DIR/mongo/db/catalog/multi_index_block',
     ],
diff --git a/src/mongo/db/auth/auth_op_observer.h b/src/mongo/db/auth/auth_op_observer.h
index 28646565929..ea4e6430c95 100644
--- a/src/mongo/db/auth/auth_op_observer.h
+++ b/src/mongo/db/auth/auth_op_observer.h
@@ -51,6 +51,25 @@ public:
                        BSONObj indexDoc,
                        bool fromMigrate) final {}
 
+    void onStartIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           CollectionUUID collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           bool fromMigrate) final {}
+
+    void onCommitIndexBuild(OperationContext* opCtx,
+                            const NamespaceString& nss,
+                            CollectionUUID collUUID,
+                            const UUID& indexBuildUUID,
+                            const std::vector<BSONObj>& indexes,
+                            bool fromMigrate) final {}
+
+    void onAbortIndexBuild(OperationContext* opCtx,
+                           CollectionUUID collUUID,
+                           const BSONObj& indexInfo,
+                           bool fromMigrate) final {}
+
     void onInserts(OperationContext* opCtx,
                    const NamespaceString& nss,
                    OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/catalog/uuid_catalog.h b/src/mongo/db/catalog/uuid_catalog.h
index ec0adbdae7e..8e6a72114fe 100644
--- a/src/mongo/db/catalog/uuid_catalog.h
+++ b/src/mongo/db/catalog/uuid_catalog.h
@@ -50,6 +50,26 @@ public:
                        CollectionUUID uuid,
                        BSONObj indexDoc,
                        bool fromMigrate) override {}
+
+    void onStartIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           CollectionUUID collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           bool fromMigrate) override {}
+
+    void onCommitIndexBuild(OperationContext* opCtx,
+                            const NamespaceString& nss,
+                            CollectionUUID collUUID,
+                            const UUID& indexBuildUUID,
+                            const std::vector<BSONObj>& indexes,
+                            bool fromMigrate) override {}
+
+    void onAbortIndexBuild(OperationContext* opCtx,
+                           CollectionUUID collUUID,
+                           const BSONObj& indexInfo,
+                           bool fromMigrate) override {}
+
     void onInserts(OperationContext* opCtx,
                    const NamespaceString& nss,
                    OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/free_mon/free_mon_op_observer.h b/src/mongo/db/free_mon/free_mon_op_observer.h
index be29495b4ef..2b52ce4fe34 100644
--- a/src/mongo/db/free_mon/free_mon_op_observer.h
+++ b/src/mongo/db/free_mon/free_mon_op_observer.h
@@ -52,6 +52,25 @@ public:
                        BSONObj indexDoc,
                        bool fromMigrate) final {}
 
+    void onStartIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           CollectionUUID collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           bool fromMigrate) final {}
+
+    void onCommitIndexBuild(OperationContext* opCtx,
+                            const NamespaceString& nss,
+                            CollectionUUID collUUID,
+                            const UUID& indexBuildUUID,
+                            const std::vector<BSONObj>& indexes,
+                            bool fromMigrate) final {}
+
+    void onAbortIndexBuild(OperationContext* opCtx,
+                           CollectionUUID collUUID,
+                           const BSONObj& indexInfo,
+                           bool fromMigrate) final {}
+
     void onInserts(OperationContext* opCtx,
                    const NamespaceString& nss,
                    OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/index_builds_coordinator.h b/src/mongo/db/index_builds_coordinator.h
index d7e90547e11..d61f4c946db 100644
--- a/src/mongo/db/index_builds_coordinator.h
+++ b/src/mongo/db/index_builds_coordinator.h
@@ -109,6 +109,15 @@ public:
                                  const std::vector<BSONObj>& indexSpecs);
 
     /**
+     * Commits the index build identified by 'buildUUID'.
+     *
+     * TODO: not yet implemented.
+     */
+    virtual Status commitIndexBuild(OperationContext* opCtx,
+                                    const std::vector<BSONObj>& specs,
+                                    const UUID& buildUUID) = 0;
+
+    /**
      * Signals all the index builds to stop and then waits for them to finish. Leaves the index
      * builds in a recoverable state.
      *
diff --git a/src/mongo/db/index_builds_coordinator_mongod.cpp b/src/mongo/db/index_builds_coordinator_mongod.cpp
index d74647a5dae..38418ef8f67 100644
--- a/src/mongo/db/index_builds_coordinator_mongod.cpp
+++ b/src/mongo/db/index_builds_coordinator_mongod.cpp
@@ -127,6 +127,13 @@ IndexBuildsCoordinatorMongod::buildIndex(OperationContext* opCtx,
     return replIndexBuildState->sharedPromise.getFuture();
 }
 
+Status IndexBuildsCoordinatorMongod::commitIndexBuild(OperationContext* opCtx,
+                                                      const std::vector<BSONObj>& specs,
+                                                      const UUID& buildUUID) {
+    // TODO: not yet implemented.
+    return Status::OK();
+}
+
 void IndexBuildsCoordinatorMongod::signalChangeToPrimaryMode() {
     stdx::unique_lock<stdx::mutex> lk(_mutex);
     _replMode = ReplState::Primary;
diff --git a/src/mongo/db/index_builds_coordinator_mongod.h b/src/mongo/db/index_builds_coordinator_mongod.h
index a3fc80d90a7..15f4995d1c5 100644
--- a/src/mongo/db/index_builds_coordinator_mongod.h
+++ b/src/mongo/db/index_builds_coordinator_mongod.h
@@ -75,6 +75,13 @@ public:
         const std::vector<BSONObj>& specs,
         const UUID& buildUUID) override;
 
+    /**
+     * TODO: not yet implemented.
+     */
+    Status commitIndexBuild(OperationContext* opCtx,
+                            const std::vector<BSONObj>& specs,
+                            const UUID& buildUUID) override;
+
     void signalChangeToPrimaryMode() override;
     void signalChangeToSecondaryMode() override;
     void signalChangeToInitialSyncMode() override;
diff --git a/src/mongo/db/op_observer.h b/src/mongo/db/op_observer.h
index 91c66abb603..ef1fb9903e3 100644
--- a/src/mongo/db/op_observer.h
+++ b/src/mongo/db/op_observer.h
@@ -90,11 +90,32 @@ public:
     };
 
     virtual ~OpObserver() = default;
+
     virtual void onCreateIndex(OperationContext* opCtx,
                                const NamespaceString& nss,
                                CollectionUUID uuid,
                                BSONObj indexDoc,
                                bool fromMigrate) = 0;
+
+    virtual void onStartIndexBuild(OperationContext* opCtx,
+                                   const NamespaceString& nss,
+                                   CollectionUUID collUUID,
+                                   const UUID& indexBuildUUID,
+                                   const std::vector<BSONObj>& indexes,
+                                   bool fromMigrate) = 0;
+
+    virtual void onCommitIndexBuild(OperationContext* opCtx,
+                                    const NamespaceString& nss,
+                                    CollectionUUID collUUID,
+                                    const UUID& indexBuildUUID,
+                                    const std::vector<BSONObj>& indexes,
+                                    bool fromMigrate) = 0;
+
+    virtual void onAbortIndexBuild(OperationContext* opCtx,
+                                   CollectionUUID collUUID,
+                                   const BSONObj& indexInfo,
+                                   bool fromMigrate) = 0;
+
     virtual void onInserts(OperationContext* opCtx,
                            const NamespaceString& nss,
                            OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/op_observer_impl.cpp b/src/mongo/db/op_observer_impl.cpp
index 34709f9bc19..3a6f75eba1f 100644
--- a/src/mongo/db/op_observer_impl.cpp
+++ b/src/mongo/db/op_observer_impl.cpp
@@ -360,6 +360,87 @@ void OpObserverImpl::onCreateIndex(OperationContext* opCtx,
                  OplogSlot());
 }
 
+void OpObserverImpl::onStartIndexBuild(OperationContext* opCtx,
+                                       const NamespaceString& nss,
+                                       CollectionUUID collUUID,
+                                       const UUID& indexBuildUUID,
+                                       const std::vector<BSONObj>& indexes,
+                                       bool fromMigrate) {
+    BSONObjBuilder oplogEntryBuilder;
+    oplogEntryBuilder.append("startIndexBuild", nss.coll());
+
+    indexBuildUUID.appendToBuilder(&oplogEntryBuilder, "indexBuildUUID");
+
+    BSONArrayBuilder indexesArr(oplogEntryBuilder.subarrayStart("indexes"));
+    for (auto indexDoc : indexes) {
+        BSONObjBuilder builder;
+        for (const auto& e : indexDoc) {
+            if (e.fieldNameStringData() != "ns"_sd)
+                builder.append(e);
+        }
+        indexesArr.append(builder.obj());
+    }
+    indexesArr.done();
+
+    logOperation(opCtx,
+                 "c",
+                 nss.getCommandNS(),
+                 collUUID,
+                 oplogEntryBuilder.done(),
+                 nullptr,
+                 fromMigrate,
+                 getWallClockTimeForOpLog(opCtx),
+                 {},
+                 kUninitializedStmtId,
+                 {},
+                 false /* prepare */,
+                 OplogSlot());
+}
+
+void OpObserverImpl::onCommitIndexBuild(OperationContext* opCtx,
+                                        const NamespaceString& nss,
+                                        CollectionUUID collUUID,
+                                        const UUID& indexBuildUUID,
+                                        const std::vector<BSONObj>& indexes,
+                                        bool fromMigrate) {
+    BSONObjBuilder oplogEntryBuilder;
+    oplogEntryBuilder.append("commitIndexBuild", nss.coll());
+
+    indexBuildUUID.appendToBuilder(&oplogEntryBuilder, "indexBuildUUID");
+
+    BSONArrayBuilder indexesArr(oplogEntryBuilder.subarrayStart("indexes"));
+    for (auto indexDoc : indexes) {
+        BSONObjBuilder builder;
+        for (const auto& e : indexDoc) {
+            if (e.fieldNameStringData() != "ns"_sd)
+                builder.append(e);
+        }
+        indexesArr.append(builder.obj());
+    }
+    indexesArr.done();
+
+    logOperation(opCtx,
+                 "c",
+                 nss.getCommandNS(),
+                 collUUID,
+                 oplogEntryBuilder.done(),
+                 nullptr,
+                 fromMigrate,
+                 getWallClockTimeForOpLog(opCtx),
+                 {},
+                 kUninitializedStmtId,
+                 {},
+                 false /* prepare */,
+                 OplogSlot());
+}
+
+void OpObserverImpl::onAbortIndexBuild(OperationContext* opCtx,
+                                       CollectionUUID collUUID,
+                                       const BSONObj& indexInfo,
+                                       bool fromMigrate) {
+    // TODO (SERVER-39067): Not yet implemented.
+}
+
 void OpObserverImpl::onInserts(OperationContext* opCtx,
                                const NamespaceString& nss,
                                OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/op_observer_impl.h b/src/mongo/db/op_observer_impl.h
index 989b7d8075e..fb1b6bd5264 100644
--- a/src/mongo/db/op_observer_impl.h
+++ b/src/mongo/db/op_observer_impl.h
@@ -46,6 +46,26 @@ public:
                        CollectionUUID uuid,
                        BSONObj indexDoc,
                        bool fromMigrate) final;
+
+    void onStartIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           CollectionUUID collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           bool fromMigrate) final;
+
+    void onCommitIndexBuild(OperationContext* opCtx,
+                            const NamespaceString& nss,
+                            CollectionUUID collUUID,
+                            const UUID& indexBuildUUID,
+                            const std::vector<BSONObj>& indexes,
+                            bool fromMigrate) final;
+
+    void onAbortIndexBuild(OperationContext* opCtx,
+                           CollectionUUID collUUID,
+                           const BSONObj& indexInfo,
+                           bool fromMigrate) final;
+
     void onInserts(OperationContext* opCtx,
                    const NamespaceString& nss,
                    OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/op_observer_impl_test.cpp b/src/mongo/db/op_observer_impl_test.cpp
index c8bd4509843..6d2af2aee90 100644
--- a/src/mongo/db/op_observer_impl_test.cpp
+++ b/src/mongo/db/op_observer_impl_test.cpp
@@ -101,6 +101,90 @@ private:
     }
 };
 
+TEST_F(OpObserverTest, StartIndexBuildExpectedOplogEntry) {
+    OpObserverImpl opObserver;
+    auto opCtx = cc().makeOperationContext();
+    auto uuid = CollectionUUID::gen();
+    NamespaceString nss("test.coll");
+    UUID indexBuildUUID = UUID::gen();
+
+    BSONObj specX = BSON("key" << BSON("x" << 1) << "name"
+                               << "x_1"
+                               << "v"
+                               << 2);
+    BSONObj specA = BSON("key" << BSON("a" << 1) << "name"
+                               << "a_1"
+                               << "v"
+                               << 2);
+    std::vector<BSONObj> specs = {specX, specA};
+
+    // Write to the oplog.
+    {
+        AutoGetDb autoDb(opCtx.get(), nss.db(), MODE_X);
+        WriteUnitOfWork wunit(opCtx.get());
+        opObserver.onStartIndexBuild(
+            opCtx.get(), nss, uuid, indexBuildUUID, specs, false /*fromMigrate*/);
+        wunit.commit();
+    }
+
+    // Create expected startIndexBuild command.
+    BSONObjBuilder startIndexBuildBuilder;
+    startIndexBuildBuilder.append("startIndexBuild", nss.coll());
+    indexBuildUUID.appendToBuilder(&startIndexBuildBuilder, "indexBuildUUID");
+    BSONArrayBuilder indexesArr(startIndexBuildBuilder.subarrayStart("indexes"));
+    indexesArr.append(specX);
+    indexesArr.append(specA);
+    indexesArr.done();
+    BSONObj startIndexBuildCmd = startIndexBuildBuilder.done();
+
+    // Ensure the startIndexBuild fields were correctly set.
+    auto oplogEntry = getSingleOplogEntry(opCtx.get());
+    auto o = oplogEntry.getObjectField("o");
+    ASSERT_BSONOBJ_EQ(startIndexBuildCmd, o);
+}
+
+TEST_F(OpObserverTest, CommitIndexBuildExpectedOplogEntry) {
+    OpObserverImpl opObserver;
+    auto opCtx = cc().makeOperationContext();
+    auto uuid = CollectionUUID::gen();
+    NamespaceString nss("test.coll");
+    UUID indexBuildUUID = UUID::gen();
+
+    BSONObj specX = BSON("key" << BSON("x" << 1) << "name"
+                               << "x_1"
+                               << "v"
+                               << 2);
+    BSONObj specA = BSON("key" << BSON("a" << 1) << "name"
+                               << "a_1"
+                               << "v"
+                               << 2);
+    std::vector<BSONObj> specs = {specX, specA};
+
+    // Write to the oplog.
+    {
+        AutoGetDb autoDb(opCtx.get(), nss.db(), MODE_X);
+        WriteUnitOfWork wunit(opCtx.get());
+        opObserver.onCommitIndexBuild(
+            opCtx.get(), nss, uuid, indexBuildUUID, specs, false /*fromMigrate*/);
+        wunit.commit();
+    }
+
+    // Create expected commitIndexBuild command.
+    BSONObjBuilder commitIndexBuildBuilder;
+    commitIndexBuildBuilder.append("commitIndexBuild", nss.coll());
+    indexBuildUUID.appendToBuilder(&commitIndexBuildBuilder, "indexBuildUUID");
+    BSONArrayBuilder indexesArr(commitIndexBuildBuilder.subarrayStart("indexes"));
+    indexesArr.append(specX);
+    indexesArr.append(specA);
+    indexesArr.done();
+    BSONObj commitIndexBuildCmd = commitIndexBuildBuilder.done();
+
+    // Ensure the commitIndexBuild fields were correctly set.
+    auto oplogEntry = getSingleOplogEntry(opCtx.get());
+    auto o = oplogEntry.getObjectField("o");
+    ASSERT_BSONOBJ_EQ(commitIndexBuildCmd, o);
+}
+
 TEST_F(OpObserverTest, CollModWithCollectionOptionsAndTTLInfo) {
     OpObserverImpl opObserver;
     auto opCtx = cc().makeOperationContext();
diff --git a/src/mongo/db/op_observer_noop.h b/src/mongo/db/op_observer_noop.h
index 469043de57f..951389c1c5c 100644
--- a/src/mongo/db/op_observer_noop.h
+++ b/src/mongo/db/op_observer_noop.h
@@ -41,6 +41,26 @@ public:
                        CollectionUUID uuid,
                        BSONObj indexDoc,
                        bool fromMigrate) override {}
+
+    void onStartIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           CollectionUUID collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           bool fromMigrate) override {}
+
+    void onCommitIndexBuild(OperationContext* opCtx,
+                            const NamespaceString& nss,
+                            CollectionUUID collUUID,
+                            const UUID& indexBuildUUID,
+                            const std::vector<BSONObj>& indexes,
+                            bool fromMigrate) override {}
+
+    void onAbortIndexBuild(OperationContext* opCtx,
+                           CollectionUUID collUUID,
+                           const BSONObj& indexInfo,
+                           bool fromMigrate) override {}
+
     void onInserts(OperationContext* opCtx,
                    const NamespaceString& nss,
                    OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/op_observer_registry.h b/src/mongo/db/op_observer_registry.h
index c64537f5104..a9630eafb42 100644
--- a/src/mongo/db/op_observer_registry.h
+++ b/src/mongo/db/op_observer_registry.h
@@ -68,6 +68,40 @@ public:
             o->onCreateIndex(opCtx, nss, uuid, indexDoc, fromMigrate);
     }
 
+    virtual void onStartIndexBuild(OperationContext* opCtx,
+                                   const NamespaceString& nss,
+                                   CollectionUUID collUUID,
+                                   const UUID& indexBuildUUID,
+                                   const std::vector<BSONObj>& indexes,
+                                   bool fromMigrate) override {
+        ReservedTimes times{opCtx};
+        for (auto& o : _observers) {
+            o->onStartIndexBuild(opCtx, nss, collUUID, indexBuildUUID, indexes, fromMigrate);
+        }
+    }
+
+    virtual void onCommitIndexBuild(OperationContext* opCtx,
+                                    const NamespaceString& nss,
+                                    CollectionUUID collUUID,
+                                    const UUID& indexBuildUUID,
+                                    const std::vector<BSONObj>& indexes,
+                                    bool fromMigrate) override {
+        ReservedTimes times{opCtx};
+        for (auto& o : _observers) {
+            o->onCommitIndexBuild(opCtx, nss, collUUID, indexBuildUUID, indexes, fromMigrate);
+        }
+    }
+
+    virtual void onAbortIndexBuild(OperationContext* opCtx,
+                                   CollectionUUID collUUID,
+                                   const BSONObj& indexInfo,
+                                   bool fromMigrate) override {
+        ReservedTimes times{opCtx};
+        for (auto& o : _observers) {
+            o->onAbortIndexBuild(opCtx, collUUID, indexInfo, fromMigrate);
+        }
+    }
+
     void onInserts(OperationContext* const opCtx,
                    const NamespaceString& nss,
                    OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/repl/oplog.cpp b/src/mongo/db/repl/oplog.cpp
index 03bc09fd04b..6eac921e114 100644
--- a/src/mongo/db/repl/oplog.cpp
+++ b/src/mongo/db/repl/oplog.cpp
@@ -65,6 +65,7 @@
 #include "mongo/db/index/index_access_method.h"
 #include "mongo/db/index/index_descriptor.h"
 #include "mongo/db/index_builder.h"
+#include "mongo/db/index_builds_coordinator.h"
 #include "mongo/db/keypattern.h"
 #include "mongo/db/logical_clock.h"
 #include "mongo/db/logical_time.h"
@@ -256,6 +257,52 @@ void setOplogCollectionName(ServiceContext* service) {
     }
 }
 
+/**
+ * Parse the given BSON array of BSON into a vector of BSON.
+ */
+StatusWith<std::vector<BSONObj>> parseBSONArrayIntoVector(const BSONElement& bsonArrayElem) {
+    invariant(bsonArrayElem.type() == Array);
+    std::vector<BSONObj> vec;
+    for (auto& bsonElem : bsonArrayElem.Obj()) {
+        if (bsonElem.type() != BSONType::Object) {
+            return {ErrorCodes::TypeMismatch,
+                    str::stream() << "The elements of '" << bsonArrayElem.fieldName()
+                                  << "' array must be objects, but found "
+                                  << typeName(bsonElem.type())};
+        }
+        BSONObjBuilder builder;
+        builder.append(bsonElem);
+        vec.emplace_back(builder.obj());
+    }
+    return vec;
+}
+
+Status startIndexBuild(OperationContext* opCtx,
+                       const UUID& collUUID,
+                       const UUID& indexBuildUUID,
+                       const BSONElement& indexesElem,
+                       OplogApplication::Mode mode) {
+    auto statusWithIndexes = parseBSONArrayIntoVector(indexesElem);
+    if (!statusWithIndexes.isOK()) {
+        return statusWithIndexes.getStatus();
+    }
+    return IndexBuildsCoordinator::get(opCtx)
+        ->buildIndex(opCtx, collUUID, statusWithIndexes.getValue(), indexBuildUUID)
+        .getStatus();
+}
+
+Status commitIndexBuild(OperationContext* opCtx,
+                        const UUID& indexBuildUUID,
+                        const BSONElement& indexesElem,
+                        OplogApplication::Mode mode) {
+    auto statusWithIndexes = parseBSONArrayIntoVector(indexesElem);
+    if (!statusWithIndexes.isOK()) {
+        return statusWithIndexes.getStatus();
+    }
+    return IndexBuildsCoordinator::get(opCtx)->commitIndexBuild(
+        opCtx, statusWithIndexes.getValue(), indexBuildUUID);
+}
+
 void createIndexForApplyOps(OperationContext* opCtx,
                             const BSONObj& indexSpec,
                             const NamespaceString& indexNss,
@@ -890,6 +937,126 @@ std::map<std::string, ApplyOpMetadata> opsMap = {
           return Status::OK();
       },
       {ErrorCodes::IndexAlreadyExists, ErrorCodes::NamespaceNotFound}}},
+    {"startIndexBuild",
+     {[](OperationContext* opCtx,
+         const char* ns,
+         const BSONElement& ui,
+         BSONObj& cmd,
+         const OpTime& opTime,
+         const OplogEntry& entry,
+         OplogApplication::Mode mode) -> Status {
+         // {
+         //     "startIndexBuild" : "coll",
+         //     "indexBuildUUID" : <UUID>,
+         //     "indexes" : [
+         //         {
+         //             "key" : {
+         //                 "x" : 1
+         //             },
+         //             "name" : "x_1",
+         //             "v" : 2
+         //         },
+         //         {
+         //             "key" : {
+         //                 "k" : 1
+         //             },
+         //             "name" : "k_1",
+         //             "v" : 2
+         //         }
+         //     ]
+         // }
+
+         // TODO (SERVER-38701): this must do nothing for applyOps. Pivot can be made on 'mode' to
+         // identify applyOps requests and take no action.
+
+         const NamespaceString nss(parseUUIDorNs(opCtx, ns, ui, cmd));
+
+         auto buildUUIDElem = cmd.getField("indexBuildUUID");
+         uassert(ErrorCodes::BadValue,
+                 "Error parsing 'startIndexBuild' oplog entry, missing required field "
+                 "'indexBuildUUID'.",
+                 buildUUIDElem.eoo());
+         UUID indexBuildUUID = uassertStatusOK(UUID::parse(buildUUIDElem));
+
+         auto indexesElem = cmd.getField("indexes");
+         uassert(ErrorCodes::BadValue,
+                 "Error parsing 'startIndexBuild' oplog entry, missing required field 'indexes'.",
+                 indexesElem.eoo());
+         uassert(ErrorCodes::BadValue,
+                 "Error parsing 'startIndexBuild' oplog entry, field 'indexes' must be an array.",
+                 indexesElem.type() == Array);
+
+         auto collUUID = uassertStatusOK(UUID::parse(ui));
+
+         return startIndexBuild(opCtx, collUUID, indexBuildUUID, indexesElem, mode);
+     }}},
+    {"commitIndexBuild",
+     {[](OperationContext* opCtx,
+         const char* ns,
+         const BSONElement& ui,
+         BSONObj& cmd,
+         const OpTime& opTime,
+         const OplogEntry& entry,
+         OplogApplication::Mode mode) -> Status {
+         // {
+         //     "commitIndexBuild" : "coll",
+         //     "indexBuildUUID" : <UUID>,
+         //     "indexes" : [
+         //         {
+         //             "key" : {
+         //                 "x" : 1
+         //             },
+         //             "name" : "x_1",
+         //             "v" : 2
+         //         },
+         //         {
+         //             "key" : {
+         //                 "k" : 1
+         //             },
+         //             "name" : "k_1",
+         //             "v" : 2
+         //         }
+         //     ]
+         // }
+
+         // TODO this must work for applyOps, which doesn't provide collection or build UUIDs. Pivot
+         // can be made on 'mode' to identify applyOps requests. (SERVER-38701).
+
+         // Ensure the collection name is specified
+         BSONElement first = cmd.firstElement();
+         invariant(first.fieldNameStringData() == "commitIndexBuild");
+         uassert(ErrorCodes::InvalidNamespace,
+                 "createIndexes value must be a string",
+                 first.type() == mongo::String);
+
+         auto buildUUIDElem = cmd.getField("indexBuildUUID");
+         uassert(ErrorCodes::BadValue,
+                 "Error parsing 'commitIndexBuild' oplog entry, missing required field "
+                 "'indexBuildUUID'.",
+                 buildUUIDElem.eoo());
+         UUID indexBuildUUID = uassertStatusOK(UUID::parse(buildUUIDElem));
+
+         auto indexesElem = cmd.getField("indexes");
+         uassert(ErrorCodes::BadValue,
+                 "Error parsing 'commitIndexBuild' oplog entry, missing required field 'indexes'.",
+                 indexesElem.eoo());
+         uassert(ErrorCodes::BadValue,
+                 "Error parsing 'commitIndexBuild' oplog entry, field 'indexes' must be an array.",
+                 indexesElem.type() == Array);
+
+         return commitIndexBuild(opCtx, indexBuildUUID, indexesElem, mode);
+     }}},
+    {"abortIndexBuild",
+     {[](OperationContext* opCtx,
+         const char* ns,
+         const BSONElement& ui,
+         BSONObj& cmd,
+         const OpTime& opTme,
+         const OplogEntry& entry,
+         OplogApplication::Mode mode) -> Status {
+         // TODO (SERVER-39067): Not yet implemented.
+         return Status::OK();
+     }}},
     {"collMod",
      {[](OperationContext* opCtx,
          const char* ns,
diff --git a/src/mongo/db/s/config_server_op_observer.h b/src/mongo/db/s/config_server_op_observer.h
index 3b128534f3d..192e7e091ef 100644
--- a/src/mongo/db/s/config_server_op_observer.h
+++ b/src/mongo/db/s/config_server_op_observer.h
@@ -52,6 +52,25 @@ public:
                        BSONObj indexDoc,
                        bool fromMigrate) override {}
 
+    void onStartIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           CollectionUUID collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           bool fromMigrate) override {}
+
+    void onCommitIndexBuild(OperationContext* opCtx,
+                            const NamespaceString& nss,
+                            CollectionUUID collUUID,
+                            const UUID& indexBuildUUID,
+                            const std::vector<BSONObj>& indexes,
+                            bool fromMigrate) override {}
+
+    void onAbortIndexBuild(OperationContext* opCtx,
+                           CollectionUUID collUUID,
+                           const BSONObj& indexInfo,
+                           bool fromMigrate) override {}
+
     void onInserts(OperationContext* opCtx,
                    const NamespaceString& nss,
                    OptionalCollectionUUID uuid,
diff --git a/src/mongo/db/s/shard_server_op_observer.h b/src/mongo/db/s/shard_server_op_observer.h
index 5261851bbb3..0e737cd66d6 100644
--- a/src/mongo/db/s/shard_server_op_observer.h
+++ b/src/mongo/db/s/shard_server_op_observer.h
@@ -53,6 +53,25 @@ public:
                        BSONObj indexDoc,
                        bool fromMigrate) override {}
 
+    void onStartIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           CollectionUUID collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           bool fromMigrate) override {}
+
+    void onCommitIndexBuild(OperationContext* opCtx,
+                            const NamespaceString& nss,
+                            CollectionUUID collUUID,
+                            const UUID& indexBuildUUID,
+                            const std::vector<BSONObj>& indexes,
+                            bool fromMigrate) override {}
+
+    void onAbortIndexBuild(OperationContext* opCtx,
+                           CollectionUUID collUUID,
+                           const BSONObj& indexInfo,
+                           bool fromMigrate) override {}
+
     void onInserts(OperationContext* opCtx,
                    const NamespaceString& nss,
                    OptionalCollectionUUID uuid,
diff --git a/src/mongo/embedded/index_builds_coordinator_embedded.cpp b/src/mongo/embedded/index_builds_coordinator_embedded.cpp
index aa161e947e1..12c1dc62487 100644
--- a/src/mongo/embedded/index_builds_coordinator_embedded.cpp
+++ b/src/mongo/embedded/index_builds_coordinator_embedded.cpp
@@ -73,6 +73,12 @@ IndexBuildsCoordinatorEmbedded::buildIndex(OperationContext* opCtx,
     return replIndexBuildState->sharedPromise.getFuture();
 }
 
+Status IndexBuildsCoordinatorEmbedded::commitIndexBuild(OperationContext* opCtx,
+                                                        const std::vector<BSONObj>& specs,
+                                                        const UUID& buildUUID) {
+    MONGO_UNREACHABLE;
+}
+
 void IndexBuildsCoordinatorEmbedded::signalChangeToPrimaryMode() {
     MONGO_UNREACHABLE;
 }
diff --git a/src/mongo/embedded/index_builds_coordinator_embedded.h b/src/mongo/embedded/index_builds_coordinator_embedded.h
index a5d2b9b207a..8b1df3ee0ff 100644
--- a/src/mongo/embedded/index_builds_coordinator_embedded.h
+++ b/src/mongo/embedded/index_builds_coordinator_embedded.h
@@ -65,6 +65,9 @@ public:
     /**
      * None of the following functions should ever be called on an embedded server node.
      */
+    Status commitIndexBuild(OperationContext* opCtx,
+                            const std::vector<BSONObj>& specs,
+                            const UUID& buildUUID) override;
     void signalChangeToPrimaryMode() override;
     void signalChangeToSecondaryMode() override;
     void signalChangeToInitialSyncMode() override;