Production-grade, stateless, in-memory format conversion library for Node.js.

Transform data between 27+ formats — including JSON, YAML, XML, TOML, CSV, BSON, MsgPack, CBOR, and many more — with a single function call. No CLI, no options, no streaming, no global state. Just pure transformation.

Install

npm install transcode-js

Requires Node.js 18+

Quick Start

import { convert } from "transcode-js";

// YAML → XML
const xml = convert.transform({
  from: "yaml",
  to: "xml",
  input: "name: Yusran\nage: 25",
});

// JSON → BSON (returns Buffer)
const bson = convert.transform({
  from: "json",
  to: "bson",
  input: '{"name": "Yusran"}',
});

// CSV → JSON
const json = convert.transform({
  from: "csv",
  to: "json",
  input: "name,age\nYusran,25\nAli,30",
});

// ENV → YAML
const yaml = convert.transform({
  from: "env",
  to: "yaml",
  input: "DB_HOST=localhost\nDB_PORT=5432",
});

API

convert.transform({ from, to, input })

| Parameter | Type | Description | | --------- | ----------------- | -------------------------------------- | | from | SupportedFormat | Source format | | to | SupportedFormat | Target format | | input | unknown | Input data (string, Buffer, or object) |

Returns: string or Buffer (see Return Type)

No additional parameters. No options. No chaining. No state.

Supported Formats

| Category | Formats | | ------------------- | -------------------------------------------------------------------------------------- | | JSON & Variants | json, json5, hjson, ndjson | | YAML | yaml, yml | | XML & Markup | xml, html | | Config | toml, ini, properties, env, dotenv, editorconfig | | Tabular | csv, tsv | | URL/Web | urlencoded, formdata | | Binary | bson, msgpack, cbor | | Enterprise | geojson, graphql-json, openapi-json, swagger-json, har, postman-collection |

Return Type

| Target Format | Return Type | | ------------------------- | ----------- | | bson, msgpack, cbor | Buffer | | Everything else | string |

// Returns string
const yaml: string = convert.transform({ from: "json", to: "yaml", input: data });

// Returns Buffer
const bson: Buffer = convert.transform({ from: "json", to: "bson", input: data });

Architecture

input → registry[from].parse() → intermediate JS object → registry[to].stringify() → output

Each format has its own isolated adapter implementing:

interface FormatAdapter {
  parse(input: unknown): unknown;
  stringify(data: unknown): string | Buffer;
}

⚠️ Lossy Conversion Warning

Format conversions can be lossy depending on the source and target formats:

• XML → JSON: Attributes, comments, and processing instructions may lose structural context
• JSON → CSV: Nested objects and arrays will be flattened or stringified
• INI/ENV → JSON: All values become strings (no type preservation)
• Binary → Text: Round-trip through binary formats (BSON, MsgPack, CBOR) is generally safe for JSON-compatible data
• NDJSON ↔ JSON: NDJSON always produces/expects arrays
• HTML → other: HTML-specific constructs (void elements, entities) may not map cleanly

Always validate output when converting between structurally different formats.

TypeScript

Full type support included:

import type { SupportedFormat, FormatAdapter, TransformInput } from "transcode-js";

License

MIT