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@azure/storage-blob

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// Copyright (c) Microsoft Corporation. // Licensed under the MIT License. import { AvroReadable } from "./AvroReadable.js"; import { AbortError } from "@azure/abort-controller"; import { Buffer } from "buffer"; const ABORT_ERROR = new AbortError("Reading from the avro stream was aborted."); export class AvroReadableFromStream extends AvroReadable { _position; _readable; toUint8Array(data) { if (typeof data === "string") { return Buffer.from(data); } return data; } constructor(readable) { super(); this._readable = readable; this._position = 0; } get position() { return this._position; } async read(size, options = {}) { if (options.abortSignal?.aborted) { throw ABORT_ERROR; } if (size < 0) { throw new Error(`size parameter should be positive: ${size}`); } if (size === 0) { return new Uint8Array(); } if (!this._readable.readable) { throw new Error("Stream no longer readable."); } // See if there is already enough data. const chunk = this._readable.read(size); if (chunk) { this._position += chunk.length; // chunk.length maybe less than desired size if the stream ends. return this.toUint8Array(chunk); } else { // register callback to wait for enough data to read return new Promise((resolve, reject) => { /* eslint-disable @typescript-eslint/no-use-before-define */ const cleanUp = () => { this._readable.removeListener("readable", readableCallback); this._readable.removeListener("error", rejectCallback); this._readable.removeListener("end", rejectCallback); this._readable.removeListener("close", rejectCallback); if (options.abortSignal) { options.abortSignal.removeEventListener("abort", abortHandler); } }; const readableCallback = () => { const callbackChunk = this._readable.read(size); if (callbackChunk) { this._position += callbackChunk.length; cleanUp(); // callbackChunk.length maybe less than desired size if the stream ends. resolve(this.toUint8Array(callbackChunk)); } }; const rejectCallback = () => { cleanUp(); reject(); }; const abortHandler = () => { cleanUp(); reject(ABORT_ERROR); }; this._readable.on("readable", readableCallback); this._readable.once("error", rejectCallback); this._readable.once("end", rejectCallback); this._readable.once("close", rejectCallback); if (options.abortSignal) { options.abortSignal.addEventListener("abort", abortHandler); } /* eslint-enable @typescript-eslint/no-use-before-define */ }); } } } //# sourceMappingURL=AvroReadableFromStream.js.map