SERVER-55288 Create RecipientStateMachineExternalState class.

1 files changed, 146 insertions, 0 deletions

diff --git a/src/mongo/db/s/resharding/resharding_recipient_service_external_state.h b/src/mongo/db/s/resharding/resharding_recipient_service_external_state.h
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index 00000000000..7a414229125
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+++ b/src/mongo/db/s/resharding/resharding_recipient_service_external_state.h
@@ -0,0 +1,146 @@
+/**
+ *    Copyright (C) 2021-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/util/functional.h"
+
+#include "mongo/base/string_data.h"
+#include "mongo/bson/timestamp.h"
+#include "mongo/db/catalog/collection_options.h"
+#include "mongo/db/s/migration_destination_manager.h"
+#include "mongo/db/s/resharding/resharding_recipient_service.h"
+#include "mongo/s/chunk_manager.h"
+#include "mongo/s/shard_id.h"
+
+namespace mongo {
+
+class BSONObj;
+class CommonReshardingMetadata;
+class NamespaceString;
+class OperationContext;
+class ServiceContext;
+
+/**
+ * Represents the interface that RecipientStateMachine uses to interact with the rest of the
+ * sharding codebase.
+ *
+ * In particular, RecipientStateMachine must not directly use Grid, ShardingState, or
+ * ShardingCatalogClient. RecipientStateMachine must instead access those types through the
+ * RecipientStateMachineExternalState interface. Having it behind an interface makes it more
+ * straightforward to unit test RecipientStateMachine.
+ */
+class ReshardingRecipientService::RecipientStateMachineExternalState {
+public:
+    virtual ~RecipientStateMachineExternalState() = default;
+
+    virtual ShardId myShardId(ServiceContext* serviceContext) const = 0;
+
+    virtual void refreshCatalogCache(OperationContext* opCtx, const NamespaceString& nss) = 0;
+
+    virtual ChunkManager getShardedCollectionRoutingInfo(OperationContext* opCtx,
+                                                         const NamespaceString& nss) = 0;
+
+    virtual MigrationDestinationManager::CollectionOptionsAndUUID getCollectionOptions(
+        OperationContext* opCtx,
+        const NamespaceString& nss,
+        const CollectionUUID& uuid,
+        Timestamp afterClusterTime,
+        StringData reason) = 0;
+
+    virtual MigrationDestinationManager::IndexesAndIdIndex getCollectionIndexes(
+        OperationContext* opCtx,
+        const NamespaceString& nss,
+        const CollectionUUID& uuid,
+        Timestamp afterClusterTime,
+        StringData reason) = 0;
+
+    virtual void withShardVersionRetry(OperationContext* opCtx,
+                                       const NamespaceString& nss,
+                                       StringData reason,
+                                       unique_function<void()> callback) = 0;
+
+    virtual void updateCoordinatorDocument(OperationContext* opCtx,
+                                           const BSONObj& query,
+                                           const BSONObj& update) = 0;
+
+    /**
+     * Creates the temporary resharding collection locally.
+     *
+     * The collection options are taken from the primary shard for the source database and the
+     * collection indexes are taken from the shard which owns the global minimum chunk.
+     *
+     * This function won't automatically create an index on the new shard key pattern.
+     */
+    void ensureTempReshardingCollectionExistsWithIndexes(OperationContext* opCtx,
+                                                         const CommonReshardingMetadata& metadata,
+                                                         Timestamp cloneTimestamp);
+};
+
+class RecipientStateMachineExternalStateImpl
+    : public ReshardingRecipientService::RecipientStateMachineExternalState {
+public:
+    ShardId myShardId(ServiceContext* serviceContext) const override;
+
+    void refreshCatalogCache(OperationContext* opCtx, const NamespaceString& nss) override;
+
+    ChunkManager getShardedCollectionRoutingInfo(OperationContext* opCtx,
+                                                 const NamespaceString& nss) override;
+
+    MigrationDestinationManager::CollectionOptionsAndUUID getCollectionOptions(
+        OperationContext* opCtx,
+        const NamespaceString& nss,
+        const CollectionUUID& uuid,
+        Timestamp afterClusterTime,
+        StringData reason) override;
+
+    MigrationDestinationManager::IndexesAndIdIndex getCollectionIndexes(OperationContext* opCtx,
+                                                                        const NamespaceString& nss,
+                                                                        const CollectionUUID& uuid,
+                                                                        Timestamp afterClusterTime,
+                                                                        StringData reason) override;
+
+    void withShardVersionRetry(OperationContext* opCtx,
+                               const NamespaceString& nss,
+                               StringData reason,
+                               unique_function<void()> callback) override;
+
+    void updateCoordinatorDocument(OperationContext* opCtx,
+                                   const BSONObj& query,
+                                   const BSONObj& update) override;
+
+private:
+    template <typename Callable>
+    auto _withShardVersionRetry(OperationContext* opCtx,
+                                const NamespaceString& nss,
+                                StringData reason,
+                                Callable&& callable);
+};
+
+}  // namespace mongo