Real-Time Event Stream Subscriber Tool

WHAT IT DOES

The Real-Time Event Stream Subscriber Tool is an analytics tool that streams live event logs from smart contracts as they are emitted on-chain. It connects to the RPC provider, tracks new blocks in near-real-time, fetches event logs from specified contracts, and displays them in a live stream. The tool supports filtering by event signature and configurable polling intervals, providing a real-time view of contract activity. This helps developers monitor contract interactions, debug event emissions, and track protocol activity without relying on external indexing services.

HOW TO USE

Enter the contract addresses you want to monitor (one per line). Optionally specify event signatures to filter the events (one per line). Set the polling interval (default 3 seconds). Click "start streaming" to begin monitoring. The tool continuously checks for new blocks, fetches events from the specified contracts, and displays them in the event stream. Each event shows the timestamp, contract address, block number, transaction hash, and topic. Use "stop" to pause the stream and "clear" to reset the event log. The stream maintains the last 100 events in memory.

TECHNICAL MECHANISM

The tool uses a polling-based approach to simulate real-time event streaming. It tracks the last checked block number and fetches new events incrementally using eth_getLogs with adaptive chunking. To handle provider block range limits, it starts with 2000-block chunks and halves the size on failure until a minimum of 100 blocks. The tool calculates the current block number at each poll interval, compares it with the last checked block, and fetches only events from new blocks. Events are aggregated by contract address and displayed with timestamp and block information. The adaptive chunking strategy is critical because public RPCs cap block ranges differently—a single refusal should not end the stream. The tool provides real-time feedback with a live dot indicator and event count updates.

WHAT IT CANNOT SEE

The tool cannot achieve true real-time performance due to RPC latency and block propagation delays. It cannot subscribe to events without continuous polling (no WebSocket support). The tool cannot guarantee that all events are captured if the provider has rate limits. It cannot detect events that are emitted through internal transactions or delegate calls. The tool cannot decode event data without the contract ABI. It cannot account for network congestion or delayed block production. The tool cannot stream events from contracts that use custom event encoding. It cannot persist event streams across page reloads.

PLEASE NOTE

This tool is designed for Ethereum Virtual Machine (EVM) compatible chains. The polling interval determines how frequently the tool checks for new blocks—shorter intervals provide more real-time updates but may increase RPC usage. The tool uses adaptive chunking to handle provider block range limits. The stream maintains the last 100 events in memory; older events are discarded. The tool provides estimates only and should be used for monitoring and debugging purposes. For production monitoring, consider using WebSocket subscriptions or dedicated indexing services.