SERVER-63521 Add UserWriteBlockModeOpObserver to enforce write blocking

1 files changed, 220 insertions, 0 deletions

diff --git a/src/mongo/db/user_write_block_mode_op_observer.h b/src/mongo/db/user_write_block_mode_op_observer.h
new file mode 100644
index 00000000000..8da805bb96f
--- /dev/null
+++ b/src/mongo/db/user_write_block_mode_op_observer.h
@@ -0,0 +1,220 @@
+/**
+ *    Copyright (C) 2022-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    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
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    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 Server Side 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 {
+
+/**
+ * OpObserver for user write blocking. On write operations, checks whether the current global user
+ * write blocking state allows the write, and uasserts if not.
+ */
+class UserWriteBlockModeOpObserver final : public OpObserver {
+    UserWriteBlockModeOpObserver(const UserWriteBlockModeOpObserver&) = delete;
+    UserWriteBlockModeOpObserver& operator=(const UserWriteBlockModeOpObserver&) = delete;
+
+public:
+    UserWriteBlockModeOpObserver() = default;
+    ~UserWriteBlockModeOpObserver() = default;
+
+    // Operations to check for allowed writes.
+
+    void onInserts(OperationContext* opCtx,
+                   const NamespaceString& nss,
+                   const UUID& uuid,
+                   std::vector<InsertStatement>::const_iterator first,
+                   std::vector<InsertStatement>::const_iterator last,
+                   bool fromMigrate) final;
+
+    void onUpdate(OperationContext* opCtx, const OplogUpdateEntryArgs& args) final;
+
+    void onDelete(OperationContext* opCtx,
+                  const NamespaceString& nss,
+                  const UUID& uuid,
+                  StmtId stmtId,
+                  const OplogDeleteEntryArgs& args) final;
+
+    // Noop operations.
+
+    void onCreateIndex(OperationContext* opCtx,
+                       const NamespaceString& nss,
+                       const UUID& uuid,
+                       BSONObj indexDoc,
+                       bool fromMigrate) final {}
+
+    void onStartIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           const UUID& collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           bool fromMigrate) final {}
+
+    void onStartIndexBuildSinglePhase(OperationContext* opCtx, const NamespaceString& nss) final {}
+
+    void onAbortIndexBuildSinglePhase(OperationContext* opCtx, const NamespaceString& nss) final {}
+
+    void onCommitIndexBuild(OperationContext* opCtx,
+                            const NamespaceString& nss,
+                            const UUID& collUUID,
+                            const UUID& indexBuildUUID,
+                            const std::vector<BSONObj>& indexes,
+                            bool fromMigrate) final {}
+
+    void onAbortIndexBuild(OperationContext* opCtx,
+                           const NamespaceString& nss,
+                           const UUID& collUUID,
+                           const UUID& indexBuildUUID,
+                           const std::vector<BSONObj>& indexes,
+                           const Status& cause,
+                           bool fromMigrate) final {}
+
+
+    void aboutToDelete(OperationContext* opCtx,
+                       const NamespaceString& nss,
+                       const UUID& uuid,
+                       const BSONObj& doc) final {}
+
+    void onInternalOpMessage(OperationContext* opCtx,
+                             const NamespaceString& nss,
+                             const boost::optional<UUID>& uuid,
+                             const BSONObj& msgObj,
+                             const boost::optional<BSONObj> o2MsgObj,
+                             const boost::optional<repl::OpTime> preImageOpTime,
+                             const boost::optional<repl::OpTime> postImageOpTime,
+                             const boost::optional<repl::OpTime> prevWriteOpTimeInTransaction,
+                             const boost::optional<OplogSlot> slot) final {}
+
+    void onCreateCollection(OperationContext* opCtx,
+                            const CollectionPtr& coll,
+                            const NamespaceString& collectionName,
+                            const CollectionOptions& options,
+                            const BSONObj& idIndex,
+                            const OplogSlot& createOpTime) final {}
+
+    void onCollMod(OperationContext* opCtx,
+                   const NamespaceString& nss,
+                   const UUID& uuid,
+                   const BSONObj& collModCmd,
+                   const CollectionOptions& oldCollOptions,
+                   boost::optional<IndexCollModInfo> indexInfo) final {}
+
+    void onDropDatabase(OperationContext* opCtx, const std::string& dbName) final {}
+
+    using OpObserver::onDropCollection;
+    repl::OpTime onDropCollection(OperationContext* opCtx,
+                                  const NamespaceString& collectionName,
+                                  const UUID& uuid,
+                                  std::uint64_t numRecords,
+                                  CollectionDropType dropType) final {
+        return repl::OpTime();
+    }
+
+    void onDropIndex(OperationContext* opCtx,
+                     const NamespaceString& nss,
+                     const UUID& uuid,
+                     const std::string& indexName,
+                     const BSONObj& indexInfo) final {}
+
+    using OpObserver::onRenameCollection;
+    void onRenameCollection(OperationContext* opCtx,
+                            const NamespaceString& fromCollection,
+                            const NamespaceString& toCollection,
+                            const UUID& uuid,
+                            const boost::optional<UUID>& dropTargetUUID,
+                            std::uint64_t numRecords,
+                            bool stayTemp) final {}
+
+    void onImportCollection(OperationContext* opCtx,
+                            const UUID& importUUID,
+                            const NamespaceString& nss,
+                            long long numRecords,
+                            long long dataSize,
+                            const BSONObj& catalogEntry,
+                            const BSONObj& storageMetadata,
+                            bool isDryRun) final {}
+
+    using OpObserver::preRenameCollection;
+    repl::OpTime preRenameCollection(OperationContext* opCtx,
+                                     const NamespaceString& fromCollection,
+                                     const NamespaceString& toCollection,
+                                     const UUID& uuid,
+                                     const boost::optional<UUID>& dropTargetUUID,
+                                     std::uint64_t numRecords,
+                                     bool stayTemp) final {
+        return repl::OpTime();
+    }
+
+    void postRenameCollection(OperationContext* opCtx,
+                              const NamespaceString& fromCollection,
+                              const NamespaceString& toCollection,
+                              const UUID& uuid,
+                              const boost::optional<UUID>& dropTargetUUID,
+                              bool stayTemp) final {}
+
+    void onApplyOps(OperationContext* opCtx,
+                    const std::string& dbName,
+                    const BSONObj& applyOpCmd) final {}
+
+    void onEmptyCapped(OperationContext* opCtx,
+                       const NamespaceString& collectionName,
+                       const UUID& uuid) final {}
+
+    void onUnpreparedTransactionCommit(OperationContext* opCtx,
+                                       std::vector<repl::ReplOperation>* statements,
+                                       size_t numberOfPrePostImagesToWrite) final {}
+
+    void onPreparedTransactionCommit(
+        OperationContext* opCtx,
+        OplogSlot commitOplogEntryOpTime,
+        Timestamp commitTimestamp,
+        const std::vector<repl::ReplOperation>& statements) noexcept final {}
+
+    void onTransactionPrepare(OperationContext* opCtx,
+                              const std::vector<OplogSlot>& reservedSlots,
+                              std::vector<repl::ReplOperation>* statements,
+                              size_t numberOfPrePostImagesToWrite) final {}
+
+    void onTransactionAbort(OperationContext* opCtx,
+                            boost::optional<OplogSlot> abortOplogEntryOpTime) final {}
+
+    void onMajorityCommitPointUpdate(ServiceContext* service,
+                                     const repl::OpTime& newCommitPoint) final {}
+
+private:
+    void _onReplicationRollback(OperationContext* opCtx, const RollbackObserverInfo& rbInfo) final {
+    }
+
+    // uasserts that a write to the given namespace is allowed under the current user write blocking
+    // setting.
+    void _checkWriteAllowed(OperationContext* opCtx, const NamespaceString& nss);
+};
+
+}  // namespace mongo