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// Copyright (c) 2017-2023 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 <workerd/util/strong-bool.h>
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#include <capnp/blob.h>
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#include <capnp/list.h>
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#include <kj/string.h>
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#include <initializer_list>
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namespace workerd::util {
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// When YES, initAutogate() ignores the WORKERD_ALL_AUTOGATES environment variable and uses only
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// the gates list that was explicitly passed in. This is used by the production server, which has
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// its own autogate test infrastructure that manages the all-autogates behavior and builds
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// selective gate configs (with forceOff / toggle support).
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WD_STRONG_BOOL(IgnoreAllAutogatesEnv);
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// Workerd-specific list of autogate keys (can also be used in internal repo).
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enum class AutogateKey {
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  TEST_WORKERD,
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  // Defers TCP socket connect() to wait for DO output gate, preventing
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  // network outputs while storage writes are pending.
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  TCP_SOCKET_CONNECT_OUTPUT_GATE,
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  V8_FAST_API,
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  // Enables support for the streaming tail worker. Note that this is currently also guarded behind
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  // an experimental compat flag.
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  STREAMING_TAIL_WORKER,
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  // Enable refactor used to consolidate the different tail worker stream implementations.
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  TAIL_STREAM_REFACTOR,
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  // Enable Rust-backed Node.js DNS implementation
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  RUST_BACKED_NODE_DNS,
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  // Use ExternalPusher instead of StreamSink to handle streams in RPC.
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  RPC_USE_EXTERNAL_PUSHER,
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  // Enable the WebAssembly.instantiate shim that detects modules exporting __instance_signal /
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  // __instance_terminated and registers them for receiving the CPU-limit shutdown signal.
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  WASM_SHUTDOWN_SIGNAL_SHIM,
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  // Enable fast TextEncoder implementation using simdutf
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  ENABLE_FAST_TEXTENCODER,
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  // Enable draining read on standard streams
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  ENABLE_DRAINING_READ_ON_STANDARD_STREAMS,
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  // Make SqlStorage::isAllowedName case-insensitive and enforce it on virtual tables (FTS5).
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  SQL_RESTRICT_RESERVED_NAMES,
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  // Increase the SQLite hard heap limit from 512 MiB to 8 GiB.
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  INCREASE_SQLITE_HARD_HEAP_LIMIT,
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  // Enable user span context propagation across worker-to-worker subrequests.
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  USER_SPAN_CONTEXT_PROPAGATION,
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  // Apply an updated default autoAllocateChunkSize for ReadableStreams
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  UPDATED_AUTO_ALLOCATE_CHUNK_SIZE,
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  // Call abortIsolate() when a Python worker encounters a fatal error.
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  PYTHON_ABORT_ISOLATE_ON_FATAL_ERROR,
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  // `jsRpcSession()` returns a session handle instead of having the call itself hang until the
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  // session is complete.
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  JSRPC_SESSION_HANDLE,
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  NumOfKeys  // Reserved for iteration.
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};
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// This class allows code changes to be rolled out independent of full binary releases. It enables
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// specific code paths to be gradually rolled out via our internal tooling.
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// See the equivalent file in our internal repo for more details.
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//
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// Workerd-specific gates can be added here.
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//
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// Usage:
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//
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//     #include <workerd/util/autogate.h>
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//     Autogate::isEnabled(AutogateKey::YOUR_FEATURE_KEY)
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//
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// When making structural changes here, ensure you align them with autogate.h in the internal repo.
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class Autogate {
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 public:
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  static bool isEnabled(AutogateKey key);
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  // Creates a global Autogate and seeds it with gates that are specified in the config.
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  //
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  // This function is not thread safe, it should be called exactly once close to the start of the
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  // process before any threads are created.
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  static void initAutogate(capnp::List<capnp::Text>::Reader autogates,
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      IgnoreAllAutogatesEnv ignoreEnv = IgnoreAllAutogatesEnv::NO);
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  // Convenience method for bin-tests to invoke initAutogate() with an appropriate config.
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  static void initAutogateNamesForTest(std::initializer_list<kj::StringPtr> gateNames);
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  // Initializes all autogates to true. Used for testing with the --all-autogates flag.
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  static void initAllAutogates();
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  // Destroys an initialized global Autogate instance. Used only for testing.
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  static void deinitAutogate();
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 private:
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  bool gates[static_cast<unsigned long>(AutogateKey::NumOfKeys)] = {};
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  Autogate() = default;
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  Autogate(capnp::List<capnp::Text>::Reader autogates);
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};
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// Retrieves the name of the gate.
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//
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// When adding a new gate, add it into this method as well.
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kj::StringPtr KJ_STRINGIFY(AutogateKey key);
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}  // namespace workerd::util