SERVER-53581: Refactor TenantMigrationAccessBlock

1 files changed, 111 insertions, 0 deletions

diff --git a/src/mongo/db/repl/tenant_migration_access_blocker_util.h b/src/mongo/db/repl/tenant_migration_access_blocker_util.h
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+++ b/src/mongo/db/repl/tenant_migration_access_blocker_util.h
@@ -0,0 +1,111 @@
+/**
+ *    Copyright (C) 2020-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/catalog/database.h"
+#include "mongo/db/commands.h"
+#include "mongo/db/commands/tenant_migration_donor_cmds_gen.h"
+#include "mongo/db/operation_context.h"
+#include "mongo/db/repl/tenant_migration_access_blocker_registry.h"
+#include "mongo/db/repl/tenant_migration_conflict_info.h"
+#include "mongo/db/repl/tenant_migration_state_machine_gen.h"
+#include "mongo/db/request_execution_context.h"
+#include "mongo/executor/task_executor.h"
+#include "mongo/rpc/get_status_from_command_result.h"
+#include "mongo/rpc/reply_builder_interface.h"
+#include "mongo/util/functional.h"
+#include "mongo/util/future.h"
+
+namespace mongo {
+
+namespace tenant_migration_access_blocker {
+
+std::shared_ptr<TenantMigrationDonorAccessBlocker> getTenantMigrationDonorAccessBlocker(
+    ServiceContext* const serviceContext, StringData tenantId);
+
+/**
+ * Returns a TenantMigrationDonorDocument constructed from the given bson doc and validate the
+ * resulting doc.
+ */
+TenantMigrationDonorDocument parseDonorStateDocument(const BSONObj& doc);
+
+/**
+ * If the operation has read concern "snapshot" or includes afterClusterTime, and the database is
+ * in the read blocking state at the given atClusterTime or afterClusterTime or the selected read
+ * timestamp, blocks until the migration is committed or aborted.
+ * TODO SERVER-53505: Change this to return
+ *                    SharedSemiFuture<TenantMigrationDonorAccessBlocker::State>.
+ */
+void checkIfCanReadOrBlock(OperationContext* opCtx, StringData dbName);
+
+/**
+ * If the operation has read concern "linearizable", throws TenantMigrationCommitted error if the
+ * database has been migrated to a different replica set.
+ */
+void checkIfLinearizableReadWasAllowedOrThrow(OperationContext* opCtx, StringData dbName);
+
+/**
+ * Throws TenantMigrationConflict if the database is being migrated and the migration is in the
+ * blocking state. Throws TenantMigrationCommitted if it is in committed.
+ */
+void onWriteToDatabase(OperationContext* opCtx, StringData dbName);
+
+/**
+ * Returns TenantMigrationConflict if the database is being migrated (even if migration is not yet
+ * in the blocking state). Returns TenantMigrationCommitted if it is in committed.
+ */
+Status checkIfCanBuildIndex(OperationContext* opCtx, StringData dbName);
+
+/**
+ * Scan config.tenantMigrationDonors and creates the necessary TenantMigrationAccessBlockers for
+ * unfinished migrations.
+ */
+void recoverTenantMigrationAccessBlockers(OperationContext* opCtx);
+
+/**
+ * Blocks until the migration commits or aborts, then returns TenantMigrationCommitted or
+ * TenantMigrationAborted.
+ */
+void handleTenantMigrationConflict(OperationContext* opCtx, Status status);
+
+/**
+ * Append a no-op to the oplog.
+ */
+void performNoopWrite(OperationContext* opCtx, StringData msg);
+
+/**
+ * Creates a view on the oplog that allows a tenant migration recipient to fetch retryable writes
+ * from a tenant migration donor.
+ */
+void createRetryableWritesView(OperationContext* opCtx, Database* db);
+
+}  // namespace tenant_migration_access_blocker
+
+}  // namespace mongo