ws-endpoint-monitor

WebSocket endpoint monitor for Substrate-based blockchain nodes with Prometheus metrics.

Overview

This tool continuously monitors the health of a single Substrate blockchain node's WebSocket endpoint by periodically connecting and fetching the finalized block head. Connection results are tracked and exposed as Prometheus metrics via an HTTP endpoint.

Installation

cargo install --path .

Usage

Basic Usage

ws-endpoint-monitor wss://your-node.example.com

Advanced Configuration

ws-endpoint-monitor \
  wss://rpc.polkadot.io \
  --monitor-interval 30 \
  --monitor-connection-timeout 5 \
  --monitor-request-timeout 10 \
  --server-addr 0.0.0.0 \
  --server-port 3000 \
  --verbose

Configuration Options

The node URL is a required positional argument:

• <NODE_URL> - WebSocket URL of the Substrate node to monitor (e.g., wss://rpc.polkadot.io)

Optional parameters:

Option	Default	Description
--monitor-interval	60	Seconds between checks
--monitor-connection-timeout	5	Connection timeout (seconds)
--monitor-request-timeout	5	RPC request timeout (seconds)
--server-addr	0.0.0.0	HTTP server bind address
--server-port	3000	HTTP server port
--verbose	false	Enable debug logging

Metrics

Metrics are available at http://<server-addr>:<server-port>/metrics in Prometheus format:

check_count{endpoint="wss://rpc.polkadot.io",result="SUCCESS"} 42
check_count{endpoint="wss://rpc.polkadot.io",result="TIMEOUT"} 3