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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
/** A TransformStream that will only read & enqueue `size` amount of bytes. * This operation is chunk based and not BYOB based, * and as such will read more than needed. * * if options.error is set, then instead of terminating the stream, * an error will be thrown. * * ```ts * import { LimitedBytesTransformStream } from "https://deno.land/std@$STD_VERSION/streams/limited_bytes_transform_stream.ts"; * const res = await fetch("https://example.com"); * const parts = res.body! * .pipeThrough(new LimitedBytesTransformStream(512 * 1024)); * ``` */export class LimitedBytesTransformStream extends TransformStream<Uint8Array, Uint8Array> { #read = 0; constructor(size: number, options: { error?: boolean } = {}) { super({ transform: (chunk, controller) => { if ((this.#read + chunk.byteLength) > size) { if (options.error) { throw new RangeError(`Exceeded byte size limit of '${size}'`); } else { controller.terminate(); } } else { this.#read += chunk.byteLength; controller.enqueue(chunk); } }, }); }}