KraiNode - JSON-RPC Playground

Postman-style JSON-RPC playground for testing blockchain RPC endpoints. It is 100% client-side and talks directly to the providers you choose.

👉 Live playground: https://krainode.krissemmy.com/playground 👉 Docs page (local): http://localhost:3000/docs

Highlights

• Multi-chain: curated endpoints across public/test networks
• Provider choice: use bundled endpoints or your own URL
• Probe first: connectivity check before firing a request
• JSON viewer/editor with pretty responses and error states
• Local persistence: recent requests + selections stay in-browser
• Zero backend: build once, host anywhere static

Quick start (local)

git clone https://github.com/krissemmy/krainode-rpc-proxy.git
cd krainode-rpc-proxy/web
npm install
npm run dev   # Vite on http://localhost:3000

What happens under the hood:

• chains.yaml in the repo root is transformed into web/public/chains.json by predev/prebuild (no manual step needed).
• The order you keep in chains.yaml is preserved; the first provider for a network becomes the default.

To preview a production build locally:

npm run build
npm run preview

Docker workflows

• Dev (hot reload on :8000): make docker-dev
• Stop dev stack: make docker-down
• Prod stack (Caddy + static app): cp env.example .env && make docker-up
  • EMAIL and APP_HOST drive Caddy TLS; see env.example.
  • Logs: make docker-logs

Deploying the static app

1. Build: cd web && npm install && npm run build (outputs to web/dist)
2. Host the dist folder on any static host.

Vercel (monorepo):

• Project root: web
• Build command: npm install && npm run build
• Output directory: dist
• SPA fallback: keep the provided vercel.json rewrite.

Netlify:

• Base directory: web
• Build command: npm install && npm run build
• Publish directory: dist

Configuration

• Chains/providers: edit chains.yaml; restart dev or rebuild to regenerate web/public/chains.json.
• Analytics (optional): set in web/.env.local

  VITE_PUBLIC_POSTHOG_KEY=
  VITE_PUBLIC_POSTHOG_HOST=
  

Project layout

krainode-rpc-proxy/
├── chains.yaml            # Source of truth for networks/providers
├── web/                   # Vite + React frontend
│   ├── src/               # Components, pages, lib, data
│   ├── public/            # Static assets + generated chains.json
│   ├── scripts/           # build-chains-json.mjs
│   └── package.json       # App scripts/deps
├── Dockerfile             # Multi-stage build -> static bundle
├── docker-compose*.yml    # Dev/prod stacks (Caddy for TLS)
└── Makefile               # Helpful commands

Make targets

• make dev Start Vite dev server (local)
• make build Build production bundle
• make clean Remove web/dist and web/node_modules
• make docker-dev Dockerized dev server on :8000
• make docker-up Prod stack (Caddy + app)
• make docker-logs Tail container logs

Supported chains (from chains.yaml)

• arbitrum (one, nova, sepolia)
• avail (mainnet, testnet-turing)
• avalanche-c-chain (mainnet, fuji)
• base (mainnet, sepolia)
• berachain (mainnet, bepolia)
• blast (mainnet, sepolia)
• celo (mainnet, sepolia)
• ethereum (mainnet, sepolia, hoodi)
• gnosis (mainnet, chiado)
• hyperevm (mainnet, testnet)
• linea (mainnet, sepolia)
• mantle (mainnet, sepolia)
• monad (mainnet, testnet)
• optimism (mainnet, sepolia)
• plasma (mainnet, testnet)
• sei-evm (mainnet, testnet)
• scroll (mainnet, sepolia)
• tempo (testnet)
• unichain (mainnet, sepolia)

Troubleshooting

• CORS/network errors: try another provider or your own endpoint.
• Chains not updating: ensure you restarted after editing chains.yaml (the pre-scripts regenerate chains.json on dev/build).
• Docker dev port in use: adjust docker-compose-dev.yml port mapping if 8000 is occupied.

Contributing

1. Fork and branch
2. npm run dev (or make dev) to iterate
3. Keep chains/providers in chains.yaml
4. Open a PR when ready

License

MIT License - see LICENSE.