JsonStream Class Reference

Description

Streaming JSON for payloads that exceed V8's max string length (0x1fffffe8 ≈ 512 MiB).

A single JS string can never hold such a payload, so JSON.parse(wholeString) / JSON.stringify(wholeObject) throw "Invalid string length". These helpers parse from / serialize to chunks and never materialize the payload as one giant string — the resulting object lives in memory (objects are not size-capped, only strings).

Environment-agnostic: works in the browser (Blob/File, ReadableStream, fetch Response) and in Node (fs read streams are async-iterable). No fs import, so it bundles safely for the browser.

Static Public Member Functions
static async	parse (source)
static *	stringifyChunks (value, chunkSize=1<< 20)

Function Documentation

parse()

async parse ( source )

static

Parse a JSON payload of any size into a JS value without ever holding it as a single string.

Accepts:

• a Blob / File (browser file upload) → uses .stream()
• a WHATWG ReadableStream (file.stream(), Response.body)
• a Response (fetch result) → uses .body
• a Node Readable stream / any async-iterable of chunks
• a Uint8Array / string (already-in-memory buffer)

Chunks may be Uint8Array (incl. Node Buffer) or string.

Parameters

{Blob|File|ReadableStream|Response|AsyncIterable|Iterable|Uint8Array|string}

source

Returns

{Promise<any>} the parsed value

stringifyChunks()

* stringifyChunks ( value, chunkSize = 1 << 20 )

static

Serialize a JS value to a sequence of string chunks (each well under the string-length cap) without ever building one giant string.

Walks the value and only ever calls JSON.stringify() on individual leaves / keys.

Consume it however the environment needs:

• Node : for (const c of JsonStream.stringifyChunks(v)) ws.write(c)
• Browser download : new Blob([...JsonStream.stringifyChunks(v)])

Matches JSON.stringify semantics: undefined/function values are dropped from objects and rendered as null in arrays.

Parameters

{any}	value
{number}	[chunkSize=1048576] flush threshold in chars (~1 MiB)

Returns

{Generator<string>}