SERVER-27301 converted OpObserver into an interface. ServiceContext should always return a valid OpObserver implementation.

20 files changed, 386 insertions, 133 deletions

diff --git a/src/mongo/db/SConscript b/src/mongo/db/SConscript
index ed5c540ab37..7a1fe1d630c 100644
--- a/src/mongo/db/SConscript
+++ b/src/mongo/db/SConscript
@@ -635,7 +635,7 @@ serverOnlyFiles = [
     "index_rebuilder.cpp",
     "instance.cpp",
     "introspect.cpp",
-    "op_observer.cpp",
+    "op_observer_impl.cpp",
     "operation_context_impl.cpp",
     "prefetch.cpp",
     "range_deleter_db_env.cpp",
@@ -740,11 +740,21 @@ env.Library(
 )
 
 env.Library(
+    target= 'op_observer_noop',
+    source= [
+        'op_observer_noop.cpp',
+    ],
+    LIBDEPS= [
+    ],
+)
+
+env.Library(
     target= 'service_context_d_test_fixture',
     source= [
         'service_context_d_test_fixture.cpp',
     ],
     LIBDEPS= [
+        'op_observer_noop',
         '$BUILD_DIR/mongo/db/serveronly',
         '$BUILD_DIR/mongo/db/storage/storage_options',
         '$BUILD_DIR/mongo/unittest/unittest',
diff --git a/src/mongo/db/catalog/collection.cpp b/src/mongo/db/catalog/collection.cpp
index 757077efb56..39bb1870256 100644
--- a/src/mongo/db/catalog/collection.cpp
+++ b/src/mongo/db/catalog/collection.cpp
@@ -417,9 +417,7 @@ Status Collection::insertDocuments(OperationContext* txn,
         return status;
     invariant(sid == txn->recoveryUnit()->getSnapshotId());
 
-    auto opObserver = getGlobalServiceContext()->getOpObserver();
-    if (opObserver)
-        opObserver->onInserts(txn, ns(), begin, end, fromMigrate);
+    getGlobalServiceContext()->getOpObserver()->onInserts(txn, ns(), begin, end, fromMigrate);
 
     txn->recoveryUnit()->onCommit([this]() { notifyCappedWaitersIfNeeded(); });
 
@@ -481,9 +479,8 @@ Status Collection::insertDocument(OperationContext* txn,
     vector<BSONObj> docs;
     docs.push_back(doc);
 
-    auto opObserver = getGlobalServiceContext()->getOpObserver();
-    if (opObserver)
-        opObserver->onInserts(txn, ns(), docs.begin(), docs.end());
+    getGlobalServiceContext()->getOpObserver()->onInserts(
+        txn, ns(), docs.begin(), docs.end(), false);
 
     txn->recoveryUnit()->onCommit([this]() { notifyCappedWaitersIfNeeded(); });
 
@@ -582,10 +579,8 @@ void Collection::deleteDocument(
 
     Snapshotted<BSONObj> doc = docFor(txn, loc);
 
-    CollectionShardingState::DeleteState deleteState;
-    auto opObserver = getGlobalServiceContext()->getOpObserver();
-    if (opObserver)
-        deleteState = opObserver->aboutToDelete(txn, ns(), doc.value());
+    auto deleteState =
+        getGlobalServiceContext()->getOpObserver()->aboutToDelete(txn, ns(), doc.value());
 
     /* check if any cursors point to us.  if so, advance them. */
     _cursorManager.invalidateDocument(txn, loc, INVALIDATION_DELETION);
@@ -598,8 +593,8 @@ void Collection::deleteDocument(
 
     _recordStore->deleteRecord(txn, loc);
 
-    if (opObserver)
-        opObserver->onDelete(txn, ns(), std::move(deleteState), fromMigrate);
+    getGlobalServiceContext()->getOpObserver()->onDelete(
+        txn, ns(), std::move(deleteState), fromMigrate);
 }
 
 Counter64 moveCounter;
@@ -723,9 +718,7 @@ StatusWith<RecordId> Collection::updateDocument(OperationContext* txn,
     invariant(sid == txn->recoveryUnit()->getSnapshotId());
     args->updatedDoc = newDoc;
 
-    auto opObserver = getGlobalServiceContext()->getOpObserver();
-    if (opObserver)
-        opObserver->onUpdate(txn, *args);
+    getGlobalServiceContext()->getOpObserver()->onUpdate(txn, *args);
 
     return {oldLocation};
 }
@@ -770,10 +763,7 @@ StatusWith<RecordId> Collection::_updateDocumentWithMove(OperationContext* txn,
     invariant(sid == txn->recoveryUnit()->getSnapshotId());
     args->updatedDoc = newDoc;
 
-    auto opObserver = getGlobalServiceContext()->getOpObserver();
-    if (opObserver) {
-        opObserver->onUpdate(txn, *args);
-    }
+    getGlobalServiceContext()->getOpObserver()->onUpdate(txn, *args);
 
     moveCounter.increment();
     if (opDebug) {
@@ -819,9 +809,7 @@ StatusWith<RecordData> Collection::updateDocumentWithDamages(
     if (newRecStatus.isOK()) {
         args->updatedDoc = newRecStatus.getValue().toBson();
 
-        auto opObserver = getGlobalServiceContext()->getOpObserver();
-        if (opObserver)
-            opObserver->onUpdate(txn, *args);
+        getGlobalServiceContext()->getOpObserver()->onUpdate(txn, *args);
     }
     return newRecStatus;
 }
diff --git a/src/mongo/db/catalog/database.cpp b/src/mongo/db/catalog/database.cpp
index af8070e66c4..7361e1f4f4c 100644
--- a/src/mongo/db/catalog/database.cpp
+++ b/src/mongo/db/catalog/database.cpp
@@ -407,9 +407,7 @@ Status Database::dropCollection(OperationContext* txn, StringData fullns) {
         }
     }
 
-    auto opObserver = getGlobalServiceContext()->getOpObserver();
-    if (opObserver)
-        opObserver->onDropCollection(txn, nss);
+    getGlobalServiceContext()->getOpObserver()->onDropCollection(txn, nss);
 
     return Status::OK();
 }
@@ -562,9 +560,8 @@ Collection* Database::createCollection(OperationContext* txn,
         }
     }
 
-    auto opObserver = getGlobalServiceContext()->getOpObserver();
-    if (opObserver)
-        opObserver->onCreateCollection(txn, nss, options, fullIdIndexSpec);
+    getGlobalServiceContext()->getOpObserver()->onCreateCollection(
+        txn, nss, options, fullIdIndexSpec);
 
     return collection;
 }
diff --git a/src/mongo/db/catalog/drop_database.cpp b/src/mongo/db/catalog/drop_database.cpp
index 8b8a992ce5e..c0698f10821 100644
--- a/src/mongo/db/catalog/drop_database.cpp
+++ b/src/mongo/db/catalog/drop_database.cpp
@@ -84,9 +84,7 @@ Status dropDatabase(OperationContext* txn, const std::string& dbName) {
 
         WriteUnitOfWork wunit(txn);
 
-        auto opObserver = getGlobalServiceContext()->getOpObserver();
-        if (opObserver)
-            opObserver->onDropDatabase(txn, dbName + ".$cmd");
+        getGlobalServiceContext()->getOpObserver()->onDropDatabase(txn, dbName + ".$cmd");
 
         wunit.commit();
     }
diff --git a/src/mongo/db/catalog/drop_indexes.cpp b/src/mongo/db/catalog/drop_indexes.cpp
index dfa22b06561..5f252685b77 100644
--- a/src/mongo/db/catalog/drop_indexes.cpp
+++ b/src/mongo/db/catalog/drop_indexes.cpp
@@ -165,9 +165,8 @@ Status dropIndexes(OperationContext* txn,
             return status;
         }
 
-        auto opObserver = getGlobalServiceContext()->getOpObserver();
-        if (opObserver)
-            opObserver->onDropIndex(txn, dbName.toString() + ".$cmd", idxDescriptor);
+        getGlobalServiceContext()->getOpObserver()->onDropIndex(
+            txn, dbName.toString() + ".$cmd", idxDescriptor);
 
         wunit.commit();
     }
diff --git a/src/mongo/db/cloner.cpp b/src/mongo/db/cloner.cpp
index a23ddd58d8e..6b3184eae4b 100644
--- a/src/mongo/db/cloner.cpp
+++ b/src/mongo/db/cloner.cpp
@@ -424,7 +424,8 @@ void Cloner::copyIndexes(OperationContext* txn,
         const string targetSystemIndexesCollectionName = to_collection.getSystemIndexesCollection();
         const char* createIndexNs = targetSystemIndexesCollectionName.c_str();
         for (auto&& infoObj : indexInfoObjs) {
-            getGlobalServiceContext()->getOpObserver()->onCreateIndex(txn, createIndexNs, infoObj);
+            getGlobalServiceContext()->getOpObserver()->onCreateIndex(
+                txn, createIndexNs, infoObj, false);
         }
     }
     wunit.commit();
diff --git a/src/mongo/db/commands/create_indexes.cpp b/src/mongo/db/commands/create_indexes.cpp
index 116a6248cc9..570d95a7bdb 100644
--- a/src/mongo/db/commands/create_indexes.cpp
+++ b/src/mongo/db/commands/create_indexes.cpp
@@ -392,10 +392,8 @@ public:
 
             for (auto&& infoObj : indexInfoObjs) {
                 std::string systemIndexes = ns.getSystemIndexesCollection();
-                auto opObserver = getGlobalServiceContext()->getOpObserver();
-                if (opObserver) {
-                    opObserver->onCreateIndex(txn, systemIndexes, infoObj);
-                }
+                getGlobalServiceContext()->getOpObserver()->onCreateIndex(
+                    txn, systemIndexes, infoObj, false);
             }
 
             wunit.commit();
diff --git a/src/mongo/db/commands/feature_compatibility_version.cpp b/src/mongo/db/commands/feature_compatibility_version.cpp
index 2e38906b685..73988bef0c7 100644
--- a/src/mongo/db/commands/feature_compatibility_version.cpp
+++ b/src/mongo/db/commands/feature_compatibility_version.cpp
@@ -227,7 +227,7 @@ void FeatureCompatibilityVersion::set(OperationContext* txn, StringData version)
             MONGO_WRITE_CONFLICT_RETRY_LOOP_BEGIN {
                 WriteUnitOfWork wuow(txn);
                 getGlobalServiceContext()->getOpObserver()->onCreateIndex(
-                    txn, autoDB.getDb()->getSystemIndexesName(), k32IncompatibleIndexSpec);
+                    txn, autoDB.getDb()->getSystemIndexesName(), k32IncompatibleIndexSpec, false);
                 wuow.commit();
             }
             MONGO_WRITE_CONFLICT_RETRY_LOOP_END(txn, "FeatureCompatibilityVersion::set", nss.ns());
diff --git a/src/mongo/db/commands/mr.cpp b/src/mongo/db/commands/mr.cpp
index 5c0b45fc6f4..5e5306f5452 100644
--- a/src/mongo/db/commands/mr.cpp
+++ b/src/mongo/db/commands/mr.cpp
@@ -510,7 +510,7 @@ void State::prepTempCollection() {
             }
             // Log the createIndex operation.
             string logNs = nsToDatabase(_config.tempNamespace) + ".system.indexes";
-            getGlobalServiceContext()->getOpObserver()->onCreateIndex(_txn, logNs, *it);
+            getGlobalServiceContext()->getOpObserver()->onCreateIndex(_txn, logNs, *it, false);
         }
         wuow.commit();
     }
diff --git a/src/mongo/db/db.cpp b/src/mongo/db/db.cpp
index abd2fbf40a4..bd99954befd 100644
--- a/src/mongo/db/db.cpp
+++ b/src/mongo/db/db.cpp
@@ -74,7 +74,7 @@
 #include "mongo/db/json.h"
 #include "mongo/db/log_process_details.h"
 #include "mongo/db/mongod_options.h"
-#include "mongo/db/op_observer.h"
+#include "mongo/db/op_observer_impl.h"
 #include "mongo/db/operation_context.h"
 #include "mongo/db/query/internal_plans.h"
 #include "mongo/db/range_deleter_service.h"
@@ -427,7 +427,7 @@ ExitCode _initAndListen(int listenPort) {
     auto globalServiceContext = getGlobalServiceContext();
 
     globalServiceContext->setFastClockSource(FastClockSourceFactory::create(Milliseconds(10)));
-    globalServiceContext->setOpObserver(stdx::make_unique<OpObserver>());
+    globalServiceContext->setOpObserver(stdx::make_unique<OpObserverImpl>());
 
     DBDirectClientFactory::get(globalServiceContext)
         .registerImplementation([](OperationContext* txn) {
diff --git a/src/mongo/db/op_observer.h b/src/mongo/db/op_observer.h
index e9c6f7d7425..15b63d89c0c 100644
--- a/src/mongo/db/op_observer.h
+++ b/src/mongo/db/op_observer.h
@@ -63,22 +63,22 @@ class OpObserver {
     MONGO_DISALLOW_COPYING(OpObserver);
 
 public:
-    OpObserver() {}
-    ~OpObserver() {}
+    OpObserver() = default;
+    virtual ~OpObserver() = default;
 
-    void onCreateIndex(OperationContext* txn,
-                       const std::string& ns,
-                       BSONObj indexDoc,
-                       bool fromMigrate = false);
-    void onInserts(OperationContext* txn,
-                   const NamespaceString& ns,
-                   std::vector<BSONObj>::const_iterator begin,
-                   std::vector<BSONObj>::const_iterator end,
-                   bool fromMigrate = false);
-    void onUpdate(OperationContext* txn, const OplogUpdateEntryArgs& args);
-    CollectionShardingState::DeleteState aboutToDelete(OperationContext* txn,
-                                                       const NamespaceString& ns,
-                                                       const BSONObj& doc);
+    virtual void onCreateIndex(OperationContext* txn,
+                               const std::string& ns,
+                               BSONObj indexDoc,
+                               bool fromMigrate) = 0;
+    virtual void onInserts(OperationContext* txn,
+                           const NamespaceString& ns,
+                           std::vector<BSONObj>::const_iterator begin,
+                           std::vector<BSONObj>::const_iterator end,
+                           bool fromMigrate) = 0;
+    virtual void onUpdate(OperationContext* txn, const OplogUpdateEntryArgs& args) = 0;
+    virtual CollectionShardingState::DeleteState aboutToDelete(OperationContext* txn,
+                                                               const NamespaceString& ns,
+                                                               const BSONObj& doc) = 0;
     /**
      * Handles logging before document is deleted.
      *
@@ -88,31 +88,35 @@ public:
      * so should be ignored by the user as an internal maintenance operation and not a
      * real delete.
      */
-    void onDelete(OperationContext* txn,
-                  const NamespaceString& ns,
-                  CollectionShardingState::DeleteState deleteState,
-                  bool fromMigrate);
-    void onOpMessage(OperationContext* txn, const BSONObj& msgObj);
-    void onCreateCollection(OperationContext* txn,
-                            const NamespaceString& collectionName,
-                            const CollectionOptions& options,
-                            const BSONObj& idIndex);
-    void onCollMod(OperationContext* txn, const std::string& dbName, const BSONObj& collModCmd);
-    void onDropDatabase(OperationContext* txn, const std::string& dbName);
-    void onDropCollection(OperationContext* txn, const NamespaceString& collectionName);
-    void onDropIndex(OperationContext* txn,
-                     const std::string& dbName,
-                     const BSONObj& idxDescriptor);
-    void onRenameCollection(OperationContext* txn,
-                            const NamespaceString& fromCollection,
-                            const NamespaceString& toCollection,
-                            bool dropTarget,
-                            bool stayTemp);
-    void onApplyOps(OperationContext* txn, const std::string& dbName, const BSONObj& applyOpCmd);
-    void onEmptyCapped(OperationContext* txn, const NamespaceString& collectionName);
-    void onConvertToCapped(OperationContext* txn,
-                           const NamespaceString& collectionName,
-                           double size);
+    virtual void onDelete(OperationContext* txn,
+                          const NamespaceString& ns,
+                          CollectionShardingState::DeleteState deleteState,
+                          bool fromMigrate) = 0;
+    virtual void onOpMessage(OperationContext* txn, const BSONObj& msgObj) = 0;
+    virtual void onCreateCollection(OperationContext* txn,
+                                    const NamespaceString& collectionName,
+                                    const CollectionOptions& options,
+                                    const BSONObj& idIndex) = 0;
+    virtual void onCollMod(OperationContext* txn,
+                           const std::string& dbName,
+                           const BSONObj& collModCmd) = 0;
+    virtual void onDropDatabase(OperationContext* txn, const std::string& dbName) = 0;
+    virtual void onDropCollection(OperationContext* txn, const NamespaceString& collectionName) = 0;
+    virtual void onDropIndex(OperationContext* txn,
+                             const std::string& dbName,
+                             const BSONObj& idxDescriptor) = 0;
+    virtual void onRenameCollection(OperationContext* txn,
+                                    const NamespaceString& fromCollection,
+                                    const NamespaceString& toCollection,
+                                    bool dropTarget,
+                                    bool stayTemp) = 0;
+    virtual void onApplyOps(OperationContext* txn,
+                            const std::string& dbName,
+                            const BSONObj& applyOpCmd) = 0;
+    virtual void onEmptyCapped(OperationContext* txn, const NamespaceString& collectionName) = 0;
+    virtual void onConvertToCapped(OperationContext* txn,
+                                   const NamespaceString& collectionName,
+                                   double size) = 0;
 };
 
 }  // namespace mongo
diff --git a/src/mongo/db/op_observer.cpp b/src/mongo/db/op_observer_impl.cpp
index 99e1fe2f649..e8b796daac2 100644
--- a/src/mongo/db/op_observer.cpp
+++ b/src/mongo/db/op_observer_impl.cpp
@@ -1,5 +1,5 @@
 /**
-*    Copyright (C) 2008-2014 MongoDB Inc.
+*    Copyright (C) 2016 MongoDB Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
@@ -28,7 +28,7 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo/db/op_observer.h"
+#include "mongo/db/op_observer_impl.h"
 
 #include "mongo/db/auth/authorization_manager_global.h"
 #include "mongo/db/catalog/collection_options.h"
@@ -45,12 +45,10 @@
 
 namespace mongo {
 
-using std::vector;
-
-void OpObserver::onCreateIndex(OperationContext* txn,
-                               const std::string& ns,
-                               BSONObj indexDoc,
-                               bool fromMigrate) {
+void OpObserverImpl::onCreateIndex(OperationContext* txn,
+                                   const std::string& ns,
+                                   BSONObj indexDoc,
+                                   bool fromMigrate) {
     repl::logOp(txn, "i", ns.c_str(), indexDoc, nullptr, fromMigrate);
     AuthorizationManager::get(txn->getServiceContext())
         ->logOp(txn, "i", ns.c_str(), indexDoc, nullptr);
@@ -63,11 +61,11 @@ void OpObserver::onCreateIndex(OperationContext* txn,
     logOpForDbHash(txn, ns.c_str());
 }
 
-void OpObserver::onInserts(OperationContext* txn,
-                           const NamespaceString& nss,
-                           vector<BSONObj>::const_iterator begin,
-                           vector<BSONObj>::const_iterator end,
-                           bool fromMigrate) {
+void OpObserverImpl::onInserts(OperationContext* txn,
+                               const NamespaceString& nss,
+                               std::vector<BSONObj>::const_iterator begin,
+                               std::vector<BSONObj>::const_iterator end,
+                               bool fromMigrate) {
     repl::logOps(txn, "i", nss, begin, end, fromMigrate);
 
     auto css = CollectionShardingState::get(txn, nss.ns());
@@ -95,7 +93,7 @@ void OpObserver::onInserts(OperationContext* txn,
     }
 }
 
-void OpObserver::onUpdate(OperationContext* txn, const OplogUpdateEntryArgs& args) {
+void OpObserverImpl::onUpdate(OperationContext* txn, const OplogUpdateEntryArgs& args) {
     // Do not log a no-op operation; see SERVER-21738
     if (args.update.isEmpty()) {
         return;
@@ -125,9 +123,9 @@ void OpObserver::onUpdate(OperationContext* txn, const OplogUpdateEntryArgs& arg
     }
 }
 
-CollectionShardingState::DeleteState OpObserver::aboutToDelete(OperationContext* txn,
-                                                               const NamespaceString& ns,
-                                                               const BSONObj& doc) {
+CollectionShardingState::DeleteState OpObserverImpl::aboutToDelete(OperationContext* txn,
+                                                                   const NamespaceString& ns,
+                                                                   const BSONObj& doc) {
     CollectionShardingState::DeleteState deleteState;
     BSONElement idElement = doc["_id"];
     if (!idElement.eoo()) {
@@ -140,10 +138,10 @@ CollectionShardingState::DeleteState OpObserver::aboutToDelete(OperationContext*
     return deleteState;
 }
 
-void OpObserver::onDelete(OperationContext* txn,
-                          const NamespaceString& ns,
-                          CollectionShardingState::DeleteState deleteState,
-                          bool fromMigrate) {
+void OpObserverImpl::onDelete(OperationContext* txn,
+                              const NamespaceString& ns,
+                              CollectionShardingState::DeleteState deleteState,
+                              bool fromMigrate) {
     if (deleteState.idDoc.isEmpty())
         return;
 
@@ -168,14 +166,14 @@ void OpObserver::onDelete(OperationContext* txn,
     }
 }
 
-void OpObserver::onOpMessage(OperationContext* txn, const BSONObj& msgObj) {
+void OpObserverImpl::onOpMessage(OperationContext* txn, const BSONObj& msgObj) {
     repl::logOp(txn, "n", "", msgObj, nullptr, false);
 }
 
-void OpObserver::onCreateCollection(OperationContext* txn,
-                                    const NamespaceString& collectionName,
-                                    const CollectionOptions& options,
-                                    const BSONObj& idIndex) {
+void OpObserverImpl::onCreateCollection(OperationContext* txn,
+                                        const NamespaceString& collectionName,
+                                        const CollectionOptions& options,
+                                        const BSONObj& idIndex) {
     std::string dbName = collectionName.db().toString() + ".$cmd";
     BSONObjBuilder b;
     b.append("create", collectionName.coll().toString());
@@ -202,9 +200,9 @@ void OpObserver::onCreateCollection(OperationContext* txn,
     logOpForDbHash(txn, dbName.c_str());
 }
 
-void OpObserver::onCollMod(OperationContext* txn,
-                           const std::string& dbName,
-                           const BSONObj& collModCmd) {
+void OpObserverImpl::onCollMod(OperationContext* txn,
+                               const std::string& dbName,
+                               const BSONObj& collModCmd) {
     BSONElement first = collModCmd.firstElement();
     std::string coll = first.valuestr();
 
@@ -217,7 +215,7 @@ void OpObserver::onCollMod(OperationContext* txn,
     logOpForDbHash(txn, dbName.c_str());
 }
 
-void OpObserver::onDropDatabase(OperationContext* txn, const std::string& dbName) {
+void OpObserverImpl::onDropDatabase(OperationContext* txn, const std::string& dbName) {
     BSONObj cmdObj = BSON("dropDatabase" << 1);
 
     repl::logOp(txn, "c", dbName.c_str(), cmdObj, nullptr, false);
@@ -226,7 +224,8 @@ void OpObserver::onDropDatabase(OperationContext* txn, const std::string& dbName
     logOpForDbHash(txn, dbName.c_str());
 }
 
-void OpObserver::onDropCollection(OperationContext* txn, const NamespaceString& collectionName) {
+void OpObserverImpl::onDropCollection(OperationContext* txn,
+                                      const NamespaceString& collectionName) {
     std::string dbName = collectionName.db().toString() + ".$cmd";
     BSONObj cmdObj = BSON("drop" << collectionName.coll().toString());
 
@@ -247,20 +246,20 @@ void OpObserver::onDropCollection(OperationContext* txn, const NamespaceString&
     logOpForDbHash(txn, dbName.c_str());
 }
 
-void OpObserver::onDropIndex(OperationContext* txn,
-                             const std::string& dbName,
-                             const BSONObj& idxDescriptor) {
+void OpObserverImpl::onDropIndex(OperationContext* txn,
+                                 const std::string& dbName,
+                                 const BSONObj& idxDescriptor) {
     repl::logOp(txn, "c", dbName.c_str(), idxDescriptor, nullptr, false);
 
     getGlobalAuthorizationManager()->logOp(txn, "c", dbName.c_str(), idxDescriptor, nullptr);
     logOpForDbHash(txn, dbName.c_str());
 }
 
-void OpObserver::onRenameCollection(OperationContext* txn,
-                                    const NamespaceString& fromCollection,
-                                    const NamespaceString& toCollection,
-                                    bool dropTarget,
-                                    bool stayTemp) {
+void OpObserverImpl::onRenameCollection(OperationContext* txn,
+                                        const NamespaceString& fromCollection,
+                                        const NamespaceString& toCollection,
+                                        bool dropTarget,
+                                        bool stayTemp) {
     std::string dbName = fromCollection.db().toString() + ".$cmd";
     BSONObj cmdObj =
         BSON("renameCollection" << fromCollection.ns() << "to" << toCollection.ns() << "stayTemp"
@@ -279,18 +278,18 @@ void OpObserver::onRenameCollection(OperationContext* txn,
     logOpForDbHash(txn, dbName.c_str());
 }
 
-void OpObserver::onApplyOps(OperationContext* txn,
-                            const std::string& dbName,
-                            const BSONObj& applyOpCmd) {
+void OpObserverImpl::onApplyOps(OperationContext* txn,
+                                const std::string& dbName,
+                                const BSONObj& applyOpCmd) {
     repl::logOp(txn, "c", dbName.c_str(), applyOpCmd, nullptr, false);
 
     getGlobalAuthorizationManager()->logOp(txn, "c", dbName.c_str(), applyOpCmd, nullptr);
     logOpForDbHash(txn, dbName.c_str());
 }
 
-void OpObserver::onConvertToCapped(OperationContext* txn,
-                                   const NamespaceString& collectionName,
-                                   double size) {
+void OpObserverImpl::onConvertToCapped(OperationContext* txn,
+                                       const NamespaceString& collectionName,
+                                       double size) {
     std::string dbName = collectionName.db().toString() + ".$cmd";
     BSONObj cmdObj = BSON("convertToCapped" << collectionName.coll() << "size" << size);
 
@@ -303,7 +302,7 @@ void OpObserver::onConvertToCapped(OperationContext* txn,
     logOpForDbHash(txn, dbName.c_str());
 }
 
-void OpObserver::onEmptyCapped(OperationContext* txn, const NamespaceString& collectionName) {
+void OpObserverImpl::onEmptyCapped(OperationContext* txn, const NamespaceString& collectionName) {
     std::string dbName = collectionName.db().toString() + ".$cmd";
     BSONObj cmdObj = BSON("emptycapped" << collectionName.coll());
 
diff --git a/src/mongo/db/op_observer_impl.h b/src/mongo/db/op_observer_impl.h
new file mode 100644
index 00000000000..d8ccfbd678d
--- /dev/null
+++ b/src/mongo/db/op_observer_impl.h
@@ -0,0 +1,86 @@
+/**
+ *    Copyright 2016 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the GNU Affero General Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include "mongo/db/op_observer.h"
+
+namespace mongo {
+
+class OpObserverImpl : public OpObserver {
+    MONGO_DISALLOW_COPYING(OpObserverImpl);
+
+public:
+    OpObserverImpl() = default;
+    virtual ~OpObserverImpl() = default;
+
+    void onCreateIndex(OperationContext* txn,
+                       const std::string& ns,
+                       BSONObj indexDoc,
+                       bool fromMigrate) override;
+    void onInserts(OperationContext* txn,
+                   const NamespaceString& ns,
+                   std::vector<BSONObj>::const_iterator begin,
+                   std::vector<BSONObj>::const_iterator end,
+                   bool fromMigrate) override;
+    void onUpdate(OperationContext* txn, const OplogUpdateEntryArgs& args) override;
+    CollectionShardingState::DeleteState aboutToDelete(OperationContext* txn,
+                                                       const NamespaceString& ns,
+                                                       const BSONObj& doc) override;
+    void onDelete(OperationContext* txn,
+                  const NamespaceString& ns,
+                  CollectionShardingState::DeleteState deleteState,
+                  bool fromMigrate) override;
+    void onOpMessage(OperationContext* txn, const BSONObj& msgObj) override;
+    void onCreateCollection(OperationContext* txn,
+                            const NamespaceString& collectionName,
+                            const CollectionOptions& options,
+                            const BSONObj& idIndex) override;
+    void onCollMod(OperationContext* txn,
+                   const std::string& dbName,
+                   const BSONObj& collModCmd) override;
+    void onDropDatabase(OperationContext* txn, const std::string& dbName) override;
+    void onDropCollection(OperationContext* txn, const NamespaceString& collectionName) override;
+    void onDropIndex(OperationContext* txn,
+                     const std::string& dbName,
+                     const BSONObj& idxDescriptor) override;
+    void onRenameCollection(OperationContext* txn,
+                            const NamespaceString& fromCollection,
+                            const NamespaceString& toCollection,
+                            bool dropTarget,
+                            bool stayTemp) override;
+    void onApplyOps(OperationContext* txn,
+                    const std::string& dbName,
+                    const BSONObj& applyOpCmd) override;
+    void onEmptyCapped(OperationContext* txn, const NamespaceString& collectionName);
+    void onConvertToCapped(OperationContext* txn,
+                           const NamespaceString& collectionName,
+                           double size) override;
+};
+
+}  // namespace mongo
diff --git a/src/mongo/db/op_observer_noop.cpp b/src/mongo/db/op_observer_noop.cpp
new file mode 100644
index 00000000000..11243595a42
--- /dev/null
+++ b/src/mongo/db/op_observer_noop.cpp
@@ -0,0 +1,80 @@
+/**
+*    Copyright (C) 2016 MongoDB Inc.
+*
+*    This program is free software: you can redistribute it and/or  modify
+*    it under the terms of the GNU Affero General Public License, version 3,
+*    as published by the Free Software Foundation.
+*
+*    This program is distributed in the hope that it will be useful,
+*    but WITHOUT ANY WARRANTY; without even the implied warranty of
+*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*    GNU Affero General Public License for more details.
+*
+*    You should have received a copy of the GNU Affero General Public License
+*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+*    As a special exception, the copyright holders give permission to link the
+*    code of portions of this program with the OpenSSL library under certain
+*    conditions as described in each individual source file and distribute
+*    linked combinations including the program with the OpenSSL library. You
+*    must comply with the GNU Affero General Public License in all respects for
+*    all of the code used other than as permitted herein. If you modify file(s)
+*    with this exception, you may extend this exception to your version of the
+*    file(s), but you are not obligated to do so. If you do not wish to do so,
+*    delete this exception statement from your version. If you delete this
+*    exception statement from all source files in the program, then also delete
+*    it in the license file.
+*/
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/db/op_observer_noop.h"
+
+namespace mongo {
+
+void OpObserverNoop::onCreateIndex(OperationContext*, const std::string&, BSONObj, bool) {}
+
+void OpObserverNoop::onInserts(OperationContext*,
+                               const NamespaceString&,
+                               std::vector<BSONObj>::const_iterator,
+                               std::vector<BSONObj>::const_iterator,
+                               bool) {}
+
+void OpObserverNoop::onUpdate(OperationContext*, const OplogUpdateEntryArgs&) {}
+
+CollectionShardingState::DeleteState OpObserverNoop::aboutToDelete(OperationContext*,
+                                                                   const NamespaceString&,
+                                                                   const BSONObj&) {
+    return {};
+}
+
+void OpObserverNoop::onDelete(OperationContext*,
+                              const NamespaceString&,
+                              CollectionShardingState::DeleteState,
+                              bool) {}
+
+void OpObserverNoop::onOpMessage(OperationContext*, const BSONObj&) {}
+
+void OpObserverNoop::onCreateCollection(OperationContext*,
+                                        const NamespaceString&,
+                                        const CollectionOptions&,
+                                        const BSONObj&) {}
+
+void OpObserverNoop::onCollMod(OperationContext*, const std::string&, const BSONObj&) {}
+
+void OpObserverNoop::onDropDatabase(OperationContext*, const std::string&) {}
+
+void OpObserverNoop::onDropCollection(OperationContext*, const NamespaceString&) {}
+
+void OpObserverNoop::onDropIndex(OperationContext*, const std::string&, const BSONObj&) {}
+
+void OpObserverNoop::onRenameCollection(
+    OperationContext*, const NamespaceString&, const NamespaceString&, bool, bool) {}
+
+void OpObserverNoop::onApplyOps(OperationContext*, const std::string&, const BSONObj&) {}
+
+void OpObserverNoop::onConvertToCapped(OperationContext*, const NamespaceString&, double) {}
+
+void OpObserverNoop::onEmptyCapped(OperationContext*, const NamespaceString&) {}
+
+}  // namespace mongo
diff --git a/src/mongo/db/op_observer_noop.h b/src/mongo/db/op_observer_noop.h
new file mode 100644
index 00000000000..f9d1e1d9182
--- /dev/null
+++ b/src/mongo/db/op_observer_noop.h
@@ -0,0 +1,86 @@
+/**
+ *    Copyright 2016 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the GNU Affero General Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include "mongo/db/op_observer.h"
+
+namespace mongo {
+
+class OpObserverNoop : public OpObserver {
+    MONGO_DISALLOW_COPYING(OpObserverNoop);
+
+public:
+    OpObserverNoop() = default;
+    virtual ~OpObserverNoop() = default;
+
+    void onCreateIndex(OperationContext* txn,
+                       const std::string& ns,
+                       BSONObj indexDoc,
+                       bool fromMigrate) override;
+    void onInserts(OperationContext* txn,
+                   const NamespaceString& ns,
+                   std::vector<BSONObj>::const_iterator begin,
+                   std::vector<BSONObj>::const_iterator end,
+                   bool fromMigrate) override;
+    void onUpdate(OperationContext* txn, const OplogUpdateEntryArgs& args) override;
+    CollectionShardingState::DeleteState aboutToDelete(OperationContext* txn,
+                                                       const NamespaceString& ns,
+                                                       const BSONObj& doc) override;
+    void onDelete(OperationContext* txn,
+                  const NamespaceString& ns,
+                  CollectionShardingState::DeleteState deleteState,
+                  bool fromMigrate) override;
+    void onOpMessage(OperationContext* txn, const BSONObj& msgObj) override;
+    void onCreateCollection(OperationContext* txn,
+                            const NamespaceString& collectionName,
+                            const CollectionOptions& options,
+                            const BSONObj& idIndex) override;
+    void onCollMod(OperationContext* txn,
+                   const std::string& dbName,
+                   const BSONObj& collModCmd) override;
+    void onDropDatabase(OperationContext* txn, const std::string& dbName) override;
+    void onDropCollection(OperationContext* txn, const NamespaceString& collectionName) override;
+    void onDropIndex(OperationContext* txn,
+                     const std::string& dbName,
+                     const BSONObj& idxDescriptor) override;
+    void onRenameCollection(OperationContext* txn,
+                            const NamespaceString& fromCollection,
+                            const NamespaceString& toCollection,
+                            bool dropTarget,
+                            bool stayTemp) override;
+    void onApplyOps(OperationContext* txn,
+                    const std::string& dbName,
+                    const BSONObj& applyOpCmd) override;
+    void onEmptyCapped(OperationContext* txn, const NamespaceString& collectionName);
+    void onConvertToCapped(OperationContext* txn,
+                           const NamespaceString& collectionName,
+                           double size) override;
+};
+
+}  // namespace mongo
diff --git a/src/mongo/db/service_context_d_test_fixture.cpp b/src/mongo/db/service_context_d_test_fixture.cpp
index 74fc3872d91..268a7cee984 100644
--- a/src/mongo/db/service_context_d_test_fixture.cpp
+++ b/src/mongo/db/service_context_d_test_fixture.cpp
@@ -37,10 +37,12 @@
 #include "mongo/db/concurrency/write_conflict_exception.h"
 #include "mongo/db/curop.h"
 #include "mongo/db/db_raii.h"
+#include "mongo/db/op_observer_noop.h"
 #include "mongo/db/operation_context.h"
 #include "mongo/db/service_context.h"
 #include "mongo/db/service_context_d.h"
 #include "mongo/db/storage/storage_options.h"
+#include "mongo/stdx/memory.h"
 #include "mongo/unittest/temp_dir.h"
 #include "mongo/util/scopeguard.h"
 
@@ -58,6 +60,7 @@ void ServiceContextMongoDTest::setUp() {
         storageGlobalParams.engineSetByUser = true;
         checked_cast<ServiceContextMongoD*>(getGlobalServiceContext())->createLockFile();
         serviceContext->initializeGlobalStorageEngine();
+        serviceContext->setOpObserver(stdx::make_unique<OpObserverNoop>());
     }
 }
 
diff --git a/src/mongo/dbtests/SConscript b/src/mongo/dbtests/SConscript
index dc30106d231..f67d20040d3 100644
--- a/src/mongo/dbtests/SConscript
+++ b/src/mongo/dbtests/SConscript
@@ -22,6 +22,7 @@ env.Library(
         'framework_options_init.cpp',
     ],
     LIBDEPS=[
+        '$BUILD_DIR/mongo/db/op_observer_noop',
         '$BUILD_DIR/mongo/db/s/sharding',
         '$BUILD_DIR/mongo/s/coreshard',
         '$BUILD_DIR/mongo/unittest/unittest',
diff --git a/src/mongo/dbtests/framework.cpp b/src/mongo/dbtests/framework.cpp
index 53826e931a0..68537ee5705 100644
--- a/src/mongo/dbtests/framework.cpp
+++ b/src/mongo/dbtests/framework.cpp
@@ -39,6 +39,7 @@
 #include "mongo/db/client.h"
 #include "mongo/db/concurrency/lock_state.h"
 #include "mongo/db/dbdirectclient.h"
+#include "mongo/db/op_observer_noop.h"
 #include "mongo/db/s/sharding_state.h"
 #include "mongo/db/service_context.h"
 #include "mongo/db/service_context_d.h"
@@ -89,6 +90,7 @@ int runDbTests(int argc, char** argv) {
 
     checked_cast<ServiceContextMongoD*>(globalServiceContext)->createLockFile();
     globalServiceContext->initializeGlobalStorageEngine();
+    globalServiceContext->setOpObserver(stdx::make_unique<OpObserverNoop>());
 
     int ret = unittest::Suite::run(frameworkGlobalParams.suites,
                                    frameworkGlobalParams.filter,
diff --git a/src/mongo/dbtests/repltests.cpp b/src/mongo/dbtests/repltests.cpp
index b17ff37767c..e547f4aa8a6 100644
--- a/src/mongo/dbtests/repltests.cpp
+++ b/src/mongo/dbtests/repltests.cpp
@@ -41,6 +41,7 @@
 #include "mongo/db/db_raii.h"
 #include "mongo/db/dbdirectclient.h"
 #include "mongo/db/json.h"
+#include "mongo/db/op_observer_impl.h"
 #include "mongo/db/ops/update.h"
 #include "mongo/db/repl/master_slave.h"
 #include "mongo/db/repl/oplog.h"
@@ -77,7 +78,7 @@ public:
         replSettings.setMaster(true);
         setGlobalReplicationCoordinator(new repl::ReplicationCoordinatorMock(replSettings));
 
-        getGlobalServiceContext()->setOpObserver(stdx::make_unique<OpObserver>());
+        getGlobalServiceContext()->setOpObserver(stdx::make_unique<OpObserverImpl>());
 
         setOplogCollectionName();
         createOplog(&_txn);
diff --git a/src/mongo/s/sharding_mongod_test_fixture.cpp b/src/mongo/s/sharding_mongod_test_fixture.cpp
index 3e8c9f013d7..41b6565ffb5 100644
--- a/src/mongo/s/sharding_mongod_test_fixture.cpp
+++ b/src/mongo/s/sharding_mongod_test_fixture.cpp
@@ -40,7 +40,7 @@
 #include "mongo/db/commands.h"
 #include "mongo/db/db_raii.h"
 #include "mongo/db/namespace_string.h"
-#include "mongo/db/op_observer.h"
+#include "mongo/db/op_observer_impl.h"
 #include "mongo/db/query/cursor_response.h"
 #include "mongo/db/query/query_request.h"
 #include "mongo/db/repl/oplog.h"
@@ -124,7 +124,7 @@ void ShardingMongodTestFixture::setUp() {
 
     repl::ReplicationCoordinator::set(serviceContext, std::move(replCoordPtr));
 
-    serviceContext->setOpObserver(stdx::make_unique<OpObserver>());
+    serviceContext->setOpObserver(stdx::make_unique<OpObserverImpl>());
     repl::setOplogCollectionName();
     repl::createOplog(_opCtx.get());
 }