RPCs

What Are RPCs?

Remote Procedure Call (RPC) endpoints are the backbone of blockchain connectivity. They allow wallets, dApps, indexers, and backend services to communicate with the Metis network—sending transactions, reading on-chain data, and subscribing to events. Every interaction with the blockchain (outside of running your own node) relies on RPC endpoints.

Types of RPC Endpoints

• Public RPCs: Free and easy to use, but subject to rate limits and congestion. Best for development, testing, and light usage.
• Private RPC Providers: Offer higher throughput, reliability, and support. Ideal for production dApps, bots, and high-traffic services.
• Self-Hosted Nodes: Maximum control, privacy, and reliability. Recommended for enterprise, indexers, or when handling sensitive data.

Common Use Cases

• Frontend dApps: Connect wallets and user interfaces to the Metis blockchain.
• Backend Services: Power bots, relayers, analytics, and automation.
• Indexers & Analytics: Aggregate and process on-chain data at scale.
• Monitoring: Track contract events, network health, and infrastructure status.

Key Considerations

• Rate Limits: Public endpoints may throttle requests. Use private or self-hosted solutions for higher limits.
• Latency: Choose geographically close endpoints to reduce response times.
• Reliability: Monitor for downtime and have fallback endpoints.
• Security: Never expose private keys to RPC endpoints you don't control. Use HTTPS and restrict access as needed.
• Compatibility: Ensure the endpoint supports all required methods (e.g., websockets for subscriptions).

All public RPCs are rate limited. If you need higher rate limits, consider the following options:

Self-Hosted

Private RPC Providers

Best Practices for Using RPCs

• Use Multiple Endpoints: Implement fallback logic to switch endpoints if one fails.
• Monitor Health: Regularly check latency and uptime of your RPC providers.
• Cache Responses: For frequently-read data, cache results to reduce load and latency.
• Secure Sensitive Operations: Only sign transactions on endpoints you trust or control.
• Stay Updated: Watch for network upgrades or endpoint deprecations from your provider.

How to Get Started

1. Choose an Endpoint: Use public endpoints for development, private or self-hosted for production.
2. Integrate in Your dApp: Configure your web3 provider (ethers.js, web3.js, etc.) with the RPC URL.
3. Test Thoroughly: Simulate high load and failover scenarios in staging.
4. Monitor and Iterate: Continuously monitor performance and update endpoints as needed.

Example: Switching RPC Endpoints in ethers.js

import { ethers } from "ethers";

const endpoints = [
  "https://andromeda.metis.io/?owner=1088",
  "https://metis-mainnet.public.blastapi.io",
  // Add more as needed
];

let provider;
for (const url of endpoints) {
  try {
    provider = new ethers.JsonRpcProvider(url);
    await provider.getBlockNumber(); // Test connectivity
    break;
  } catch (e) {
    // Try next endpoint
  }
}

if (!provider) throw new Error("No healthy RPC endpoints available");