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system_chain - Moonriver RPC Method

Get the chain name on Moonriver. Essential for network identification, multi-chain applications, and verifying the correct network connection.

Returns the chain name of the Moonriver network. This identifies the specific chain or network the node is connected to (e.g., "Polkadot", "Kusama", "Westend").

Why Moonriver? Build on the Moonbeam canary network on Kusama for real-world testing of EVM dApps with Moonbeam code ships here first, full EVM compatibility on Kusama, 80% fee burn mechanism, and XCM cross-chain messaging.

When to Use This Method

system_chain is essential for dApp developers testing on Kusama, early adopters, and teams requiring production-ready experimentation:

  • Network Verification -- Confirm your application is connected to the correct Moonriver network before processing transactions
  • Multi-Chain Applications -- Dynamically identify which Substrate chain you are interacting with in cross-chain or multi-network dApps
  • UI Display -- Show the connected network name in wallet interfaces and dashboards for production-grade dApp testing, early feature deployment, and Kusama-based EVM applications
  • Configuration Validation -- Verify endpoint configuration matches the expected chain during deployment

Code Examples

Common Use Cases

1. Network Connection Verification

Validate that your application connects to the correct chain before processing any transactions:

JavaScript
import { ApiPromise, WsProvider } from '@polkadot/api';

async function connectAndVerify(endpoint, expectedChain) {
  const provider = new WsProvider(endpoint);
  const api = await ApiPromise.create({ provider });

  const chain = await api.rpc.system.chain();
  const chainName = chain.toString();

  if (chainName !== expectedChain) {
    await api.disconnect();
    throw new Error(
      `Expected "${expectedChain}" but connected to "${chainName}"`
    );
  }

  console.log(`Verified connection to ${chainName}`);
  return api;
}

// Usage
const api = await connectAndVerify('https://api-moonriver.n.dwellir.com/YOUR_API_KEY', 'Moonriver');

2. Multi-Chain Router

Route operations based on detected chain identity:

JavaScript
async function getChainConfig(api) {
  const [chain, properties] = await Promise.all([
    api.rpc.system.chain(),
    api.rpc.system.properties()
  ]);

  const chainName = chain.toString();
  const configs = {
    Polkadot: { explorer: 'https://polkadot.subscan.io', confirmations: 1 },
    Kusama: { explorer: 'https://kusama.subscan.io', confirmations: 1 },
  };

  const config = configs[chainName] || { explorer: null, confirmations: 1 };

  return {
    name: chainName,
    tokenSymbol: properties.tokenSymbol.toString(),
    tokenDecimals: properties.tokenDecimals.toJSON(),
    ...config
  };
}

3. Health Check with Chain Identity

Include chain identity in health-check monitoring:

JavaScript
async function healthCheck(api) {
  const [chain, name, version] = await Promise.all([
    api.rpc.system.chain(),
    api.rpc.system.name(),
    api.rpc.system.version()
  ]);

  return {
    status: 'healthy',
    chain: chain.toString(),
    nodeImplementation: name.toString(),
    nodeVersion: version.toString(),
    timestamp: new Date().toISOString()
  };
}

Error Handling

Common errors and solutions:

Error CodeDescriptionSolution
-32603Internal errorNode may be starting up -- retry after delay
-32005Rate limit exceededReduce request frequency or implement client-side rate limiting
Connection refusedNode unreachableVerify the RPC endpoint URL and that the node is running

system_health

Check node health status on Moonriver. Returns peer count, sync status, and connectivity — essential for monitoring, load balancing, and infrastructure management on the Moonbeam canary network on Kusama for real-world testing of EVM dApps.

system_version

Get the node implementation version on Moonriver. Essential for compatibility checking, runtime upgrades, and monitoring node deployments across the the Moonbeam canary network on Kusama for real-world testing of EVM dApps network.

On this page

When to Use This Method
Code Examples
Common Use Cases
1. Network Connection Verification
2. Multi-Chain Router
3. Health Check with Chain Identity
Error Handling
Related Methods