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#pragma once
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#include "transform.h"
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#include <workerd/jsg/jsg.h>
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namespace workerd::api {
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// The IdentityTransformStream is a non-standard TransformStream implementation that passes
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// the exact bytes written to the writable side on to the readable side without modification.
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// Unlike standard the TransformStream, the readable side of an IdentityTransformStream
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// supports BYOB reads.
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//
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// The IdentityTransformStream is a kj-based implementation backed by a ReadableStreamSource
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// and WritableStreamSink implementation. It is a legacy class that was created before the
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// standard TransformStream constructor was available in workers. It is maintained for
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// backwards compatibility but otherwise has no special significance.
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class IdentityTransformStream: public TransformStream {
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 public:
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  using TransformStream::TransformStream;
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  struct QueuingStrategy {
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    jsg::Optional<uint64_t> highWaterMark;
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    JSG_STRUCT(highWaterMark);
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  };
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  static jsg::Ref<IdentityTransformStream> constructor(
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      jsg::Lock& js, jsg::Optional<QueuingStrategy> queuingStrategy = kj::none);
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  JSG_RESOURCE_TYPE(IdentityTransformStream) {
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    JSG_INHERIT(TransformStream);
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    JSG_TS_OVERRIDE(extends TransformStream<ArrayBuffer | ArrayBufferView, Uint8Array>);
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  }
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};
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// Same as an IdentityTransformStream, except with a known length in bytes on the readable side.
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// We don't currently enforce this limit -- it just convinces the kj-http layer to
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// emit a Content-Length (assuming it doesn't get gzipped or anything).
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class FixedLengthStream: public IdentityTransformStream {
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 public:
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  using IdentityTransformStream::IdentityTransformStream;
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  static jsg::Ref<FixedLengthStream> constructor(jsg::Lock& js,
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      uint64_t expectedLength,
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      jsg::Optional<QueuingStrategy> queuingStrategy = kj::none);
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  JSG_RESOURCE_TYPE(FixedLengthStream) {
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    JSG_INHERIT(IdentityTransformStream);
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  }
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};
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struct OneWayPipe {
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  kj::Own<ReadableStreamSource> in;
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  kj::Own<WritableStreamSink> out;
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};
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OneWayPipe newIdentityPipe(kj::Maybe<uint64_t> expectedLength = kj::none);
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bool isIdentityTransformStream(WritableStreamSink& sink);
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}  // namespace workerd::api