rpc-read-proxy

A minimum, cached, read-only proxy for Ethereum JSON-RPC requests, optimized for frontend.

Local Development

bun i
bun dev

Deployment

Authentication

Create an API token at https://dash.cloudflare.com/profile/api-tokens with the "Edit Cloudflare Workers" template.

Set RPC URLs

cp .secrets.example .secrets  # Add your RPC URLs
CLOUDFLARE_API_TOKEN=******** bun secrets # Upload to Cloudflare

Deploy

CLOUDFLARE_API_TOKEN=******** bun deploy

Cleanup

Destroy personal tokens after use.

CI/CD

Pushes to main auto-deploy via GitHub Actions.

Setup:

1. Create a long-lived API token at https://dash.cloudflare.com/profile/api-tokens

   • Use "Edit Cloudflare Workers" template
   • Scope to your specific account
   • No expiration (or 1 year)
   • Name it clearly, e.g. GitHub Actions - rpc-read-proxy

2. Add the token to GitHub repo secrets:

   • Settings → Secrets and variables → Actions → New repository secret
   • Name: CLOUDFLARE_API_TOKEN
   • Value: your token

Configuration

Variable	Description	Default
RPC_URI_FOR_[chainId]	Upstream RPC URL for chain (secret)	-
LATEST_TTL	Cache TTL for latest block queries (seconds)	3
HISTORICAL_TTL	Cache TTL for numeric block queries (seconds)	3600

TTLs are configured in wrangler.toml. RPC URLs are stored as secrets on Cloudflare.

Endpoint

POST /chain/[chainId]

Caching

Uses Cloudflare's Cache API to cache POST responses at the edge:

• Queries with latest, pending, or absent block parameters are cached for LATEST_TTL seconds (default: 3)
• Queries with numeric block parameters are cached for HISTORICAL_TTL seconds (default: 3600)
• Batch requests cache each item individually for maximum cache efficiency

Cache keys are generated from the chain ID, method name, and a SHA-256 hash of canonicalized parameters.

Rate Limiting

Configure rate limiting via Cloudflare's WAF in the dashboard at the domain level:

Setup: Domains → the proxy's public domain → Security → Security rules