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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
import type { JsonValue, ParseStreamOptions } from "./common.ts";import { parse } from "./_common.ts";
const branks = /^[ \t\r\n]*$/;function isBrankString(str: string) {  return branks.test(str);}
/** * Parse each chunk as JSON. * * This can be used to parse [JSON lines](https://jsonlines.org/), [NDJSON](http://ndjson.org/) and [JSON Text Sequences](https://datatracker.ietf.org/doc/html/rfc7464). * Chunks consisting of spaces, tab characters, or newline characters will be ignored. * * @example * parse JSON lines or NDJSON * ```ts * import { TextLineStream } from "https://deno.land/std@$STD_VERSION/streams/text_line_stream.ts"; * import { JsonParseStream } from "https://deno.land/std@$STD_VERSION/json/json_parse_stream.ts"; * * const url = "https://deno.land/std@$STD_VERSION/json/testdata/test.jsonl"; * const { body } = await fetch(url); * * const readable = body! *   .pipeThrough(new TextDecoderStream())  // convert Uint8Array to string *   .pipeThrough(new TextLineStream()) // transform into a stream where each chunk is divided by a newline *   .pipeThrough(new JsonParseStream()); // parse each chunk as JSON * * for await (const data of readable) { *   console.log(data); * } * ``` * * @example * parse JSON Text Sequences * ```ts * import { TextDelimiterStream } from "https://deno.land/std@$STD_VERSION/streams/text_delimiter_stream.ts"; * import { JsonParseStream } from "https://deno.land/std@$STD_VERSION/json/json_parse_stream.ts"; * * const url = *   "https://deno.land/std@$STD_VERSION/json/testdata/test.json-seq"; * const { body } = await fetch(url); * * const delimiter = "\x1E"; * const readable = body! *   .pipeThrough(new TextDecoderStream()) *   .pipeThrough(new TextDelimiterStream(delimiter)) // transform into a stream where each chunk is divided by a delimiter *   .pipeThrough(new JsonParseStream()); * * for await (const data of readable) { *   console.log(data); * } * ``` */export class JsonParseStream extends TransformStream<string, JsonValue> {  /**   * @param options   * @param options.writableStrategy Controls the buffer of the TransformStream used internally. Check https://developer.mozilla.org/en-US/docs/Web/API/TransformStream/TransformStream.   * @param options.readableStrategy Controls the buffer of the TransformStream used internally. Check https://developer.mozilla.org/en-US/docs/Web/API/TransformStream/TransformStream.   */  constructor({ writableStrategy, readableStrategy }: ParseStreamOptions = {}) {    super(      {        transform(chunk, controller) {          if (!isBrankString(chunk)) {            controller.enqueue(parse(chunk));          }        },      },      writableStrategy,      readableStrategy,    );  }}