@uchina-systems/csv-to-json

CSV → JSON converter with a hybrid runtime: WASM for Edge/Browser, and a native N-API add-on for Node. One npm package that “just works” everywhere with the same API.

Install

npm install @uchina-systems/csv-to-json

What you get

• Edge/Browser: WebAssembly build for fast client/edge parsing and validation
• Node: Native add-on for server-side throughput
• Unified API with options, including header handling, delimiter, and optional case normalization

JavaScript/TypeScript usage

The package auto-selects the correct runtime via conditional exports. You can import the same way in Node, Edge, and the browser.

Node (native)

import { parse, parseToArray } from '@uchina-systems/csv-to-json'
import fs from 'node:fs'

const csv = fs.readFileSync('data.csv')
const json = parse(csv, { headers: true, caseStyle: 'pascal' })
console.log(json)

const rows = parseToArray(csv, { headers: true, caseStyle: 'pascal' })
console.log(rows)

Edge/Browser (WASM)

import { parse, parseToArray } from '@uchina-systems/csv-to-json'

const bytes = new TextEncoder().encode('YouTube link,IMPORT\nhttps://yt.com,YES\n')
const json = parse(bytes, { headers: true, caseStyle: 'pascal' })
// => [{"YouTubeLink":"https://yt.com","Import":"YES"}]

const rows = parseToArray(bytes, { headers: true, caseStyle: 'pascal' })
// => [{ YouTubeLink: 'https://yt.com', Import: 'YES' }]

Next.js examples

Edge route (app/api/parse/route.ts)

export const runtime = 'edge'
import { NextResponse } from 'next/server'
import { parse } from '@uchina-systems/csv-to-json'

export async function POST(req: Request) {
  const bytes = new Uint8Array(await req.arrayBuffer())
  const json = parse(bytes, { headers: true, caseStyle: 'pascal' })
  return NextResponse.json(JSON.parse(json))
}

Node route (app/api/parse/route.ts)

export const runtime = 'nodejs'
import { NextResponse } from 'next/server'
import { parse } from '@uchina-systems/csv-to-json'

export async function POST(req: Request) {
  const bytes = new Uint8Array(await req.arrayBuffer())
  const json = parse(bytes, { headers: true, caseStyle: 'pascal' })
  return NextResponse.json(JSON.parse(json))
}

API

export type CaseStyle = 'pascal' | 'camel' | 'snake' | 'kebab' | 'title' | 'lower' | 'upper'

export interface ParseOptions {
  headers?: boolean            // default: true
  delimiter?: number           // default: 44 (",")
  caseStyle?: CaseStyle        // optional key normalization (headers only)
}

// Returns JSON string of an array of objects
export function parse(bytes: Uint8Array, options?: ParseOptions): string

// Returns parsed objects directly
export function parseToArray(bytes: Uint8Array, options?: ParseOptions): Array<Record<string, string>>

Case normalization

• Examples with caseStyle: 'pascal'
  • "YouTube link" → "YouTubeLink"
  • "IMPORT" → "Import"
  • Mixed-case tokens like "YouTube" are preserved

Browser demo

npm run demo
# Opens http://localhost:5173/examples/browser.html

.NET usage (C#)

This repo includes a .NET wrapper and a Rust C ABI. You can use the packaged DLL to call the same parser from C#.

Quick start (local build)

# Build native library for your current platform and copy into runtimes/
node scripts/build-dotnet.mjs

# Create the NuGet package (includes the native library under runtimes/<rid>/native)
dotnet build ./dotnet/Csvjson/Csvjson.csproj -c Release
# or: dotnet pack ./dotnet/Csvjson/Csvjson.csproj -c Release

Then reference the produced package (YourScope.Csvjson.0.1.0.nupkg) in your .NET solution, or reference the project directly.

C# example

using System.Text;
using Csvjson;

var csv = "YouTube link,IMPORT\nhttps://yt.com,YES\n";
var bytes = Encoding.UTF8.GetBytes(csv);
var json = Parser.Parse(bytes, headers: true, delimiter: null, caseStyle: "pascal");
Console.WriteLine(json);

Notes

• The NuGet currently includes a macOS arm64 native library when built on that platform. To support more RIDs (linux-x64, win-x64, etc.), repeat the native build on those platforms (or cross-compile) and place the outputs under dotnet/Csvjson/runtimes/<rid>/native/ before packing.
• NPM package automatically selects WASM (Edge/Browser) or the native add-on (Node) via conditional exports.

Build from source (npm)

npm run build

License

MIT OR Apache-2.0