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// Copyright (c) 2017-2022 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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// Implementations of ReadableStreamSource / WritableStreamSink which wrap system streams (sockets),
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// handle encoding/decoding, and optimize pumping between them when possible.
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#include "http.h"
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#include <workerd/api/streams/common.h>  // for StreamEncoding, ...
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#include <workerd/io/compatibility-date.capnp.h>
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#include <workerd/io/io-context.h>
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namespace workerd::api {
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// A ReadableStreamSource which automatically decodes its underlying stream. It does so lazily -- if
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// one of the `tryRead()` overloads is never called, then a `pumpTo()` to a WritableStreamSink
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// returned by `newSystemStream()` of the same encoding will not cause any decoding/encoding steps.
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//
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// NOTE: `inner` must be wholly-owned. In particular, it cannot contain references to JavaScript
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//   heap objects, as the stream is allowed to outlive the isolate, especially in the case of
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//   deferred proxying. If the inner stream for some reason contains JS references, you'll need
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//   to provide your own implementation of ReadableStreamSource.
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kj::Own<ReadableStreamSource> newSystemStream(kj::Own<kj::AsyncInputStream> inner,
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    StreamEncoding encoding,
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    IoContext& context = IoContext::current());
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// A WritableStreamSink which automatically encodes its underlying stream.
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//
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// NOTE: As with the other overload of newSystemStream(), `inner` must be wholly owned.
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kj::Own<WritableStreamSink> newSystemStream(kj::Own<kj::AsyncOutputStream> inner,
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    StreamEncoding encoding,
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    IoContext& context = IoContext::current());
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struct SystemMultiStream {
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  kj::Own<ReadableStreamSource> readable;
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  kj::Own<WritableStreamSink> writable;
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};
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// A combo ReadableStreamSource and WritableStreamSink.
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SystemMultiStream newSystemMultiStream(kj::RefcountedWrapper<kj::Own<kj::AsyncIoStream>>& stream,
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    IoContext& context = IoContext::current());
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struct ContentEncodingOptions {
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  bool brotliEnabled = false;
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  ContentEncodingOptions() = default;
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  ContentEncodingOptions(CompatibilityFlags::Reader flags);
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};
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// Get the Content-Encoding header from an HttpHeaders object as a StreamEncoding enum. Unsupported
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// encodings return IDENTITY.
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StreamEncoding getContentEncoding(IoContext& context,
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    const kj::HttpHeaders& headers,
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    Response::BodyEncoding bodyEncoding = Response::BodyEncoding::AUTO,
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    ContentEncodingOptions options = {});
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}  // namespace workerd::api