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// Copyright (c) 2022-2023 Cloudflare, Inc.
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// Licensed under the Apache 2.0 license found in the LICENSE file or at:
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//     https://opensource.org/licenses/Apache-2.0
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#pragma once
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#include <kj/common.h>
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#include <kj/string.h>
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namespace workerd {
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// This class wraps common values and functions for interacting durable object (actor) storage.
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class ActorStorageLimits {
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 public:
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  // We grant some extra cushion on top of the advertised max size in order
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  // to avoid penalizing people for pushing right up against the advertised size.
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  // The v8 serialization method we use can add a few extra bytes for its type tag
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  // and other metadata, such as the length of a string or number of items in an
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  // array. The most important cases (where users are most likely to try to
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  // intentionally run right up against the limit) are Strings and ArrayBuffers,
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  // which each get 4 bytes of metadata attached when encoded. We throw a little
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  // extra on just for future proofing and an abundance of caution.
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  //
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  // If you're curious why we add 34 bytes of cushion -- we used to add 32, but
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  // then started writing v8 serialization headers, which are 2 bytes, and didn't
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  // want to stop accepting values that we accepted before writing headers.
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  static constexpr size_t ADVERTISED_MAX_VALUE_SIZE = 128 * 1024;
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  static constexpr size_t ENFORCED_MAX_VALUE_SIZE = ADVERTISED_MAX_VALUE_SIZE + 34;
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  static constexpr size_t MAX_KEY_SIZE = 2048;
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  static void checkMaxKeySize(kj::StringPtr key);
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  static void checkMaxValueSize(kj::StringPtr key, kj::ArrayPtr<const kj::byte> value);
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  static void checkMaxPairsCount(size_t count);
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};
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}  // namespace workerd