web3_clientVersion | Moonbase Alpha RPC Docs

Get the client software version of your Moonbase Alpha node. Essential for compatibility checks, fleet monitoring, and debugging client-specific behavior.

Returns the current client software version string for your Moonbase Alpha node, including the client name, version number, OS, and runtime.

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When to Use This Method

web3_clientVersion is valuable for Moonbeam developers, dApp testers, and teams validating cross-chain integrations:

Client Compatibility Checks — Verify the node runs a client version that supports the RPC methods your application needs
Fleet Version Monitoring — Track client versions across a multi-node infrastructure to coordinate upgrades
Debugging Client-Specific Behavior — Identify which client (Geth, Erigon, Nethermind, Besu, etc.) is serving requests when behavior differs
Security Auditing — Detect nodes running outdated versions with known vulnerabilities

Code Examples

Common Use Cases

1. Client Version Parser

Parse the version string to extract structured information:

JavaScript

function parseClientVersion(versionString) {
  const parts = versionString.split('/');

  return {
    client: parts[0],
    version: parts[1] || 'unknown',
    os: parts[2] || 'unknown',
    runtime: parts[3] || 'unknown'
  };
}

async function getNodeInfo(provider) {
  const version = await provider.send('web3_clientVersion', []);
  const parsed = parseClientVersion(version);

  console.log(`Client: ${parsed.client}`);
  console.log(`Version: ${parsed.version}`);
  console.log(`OS: ${parsed.os}`);
  console.log(`Runtime: ${parsed.runtime}`);

  return parsed;
}

2. Fleet Version Audit

Check all nodes in a fleet and report version inconsistencies:

Python

import requests

def audit_fleet_versions(endpoints):
    versions = {}
    for endpoint in endpoints:
        try:
            response = requests.post(
                endpoint,
                json={'jsonrpc': '2.0', 'method': 'web3_clientVersion', 'params': [], 'id': 1},
                timeout=5
            )
            version = response.json()['result']
            versions[endpoint] = version
        except Exception as e:
            versions[endpoint] = f'ERROR: {e}'

    # Group by client version
    grouped = {}
    for endpoint, version in versions.items():
        grouped.setdefault(version, []).append(endpoint)

    for version, nodes in grouped.items():
        print(f'{version}: {len(nodes)} node(s)')

    if len(grouped) > 1:
        print('WARNING: Inconsistent versions detected across fleet')

    return versions

3. Feature Detection by Client

Adjust RPC behavior based on the detected client type: