Hyperion Stream Client (v3.6+)

The Hyperion Stream Client is a powerful TypeScript/JavaScript library for connecting to and streaming real-time or historical data from Hyperion History API servers (version 3.6 and newer).

It simplifies handling WebSocket connections, message parsing, and stream management.

Compatibility Note: Hyperion Stream Client v3.6 is only compatible with Hyperion servers from v3.6 onwards.

Key Features

• Real-time Data Feeds: Subscribe to live streams of blockchain actions and table state changes (deltas) as they occur.
• Historical Data Replay: Efficiently fetch and process historical sequences of actions or deltas, with precise control over block ranges.
• Simplified Development: Avoids the need to implement custom WebSocket handling and data deserialization logic.
• Flexible Data Consumption: Choose between an intuitive event-driven API (stream.on('message', ...)) or the modern AsyncIterator pattern (for await...of stream) for processing data.
• Robust Filtering: Utilize Hyperion's server-side filtering to receive only the data relevant to your application, saving bandwidth and client-side processing.
• Cross-Environment Support: Seamlessly integrate into Node.js (v18+) backends or modern browser-based applications.
• Automatic Reconnection: Leverages socket.io-client's robust reconnection capabilities.
• Debug Mode: Optional detailed logging for development.

Prerequisites

• Hyperion API Endpoint: Access to a running Hyperion History API (v3.6+) instance that has streaming enabled. You can find a list of public endpoints here.
• Node.js: Version 18 or higher is required for server-side usage or for building/bundling for the browser. For direct In-Browser usage see here

Installation

Install the client using npm or yarn:

npm install @eosrio/hyperion-stream-client --save

or

yarn add @eosrio/hyperion-stream-client

Getting Started

Ready to dive in?

• For a quick hands-on example, see:

Getting Started

• To understand how to configure the client, visit:

Client Configuration

Further Reading

Explore the following sections to learn more about specific aspects of the Hyperion Stream Client:

• Streaming Actions: Detailed guide on requesting and filtering action streams.
• Streaming Table Deltas: Comprehensive information on streaming table state changes.
• Handling Stream Data: Learn about the event-driven API, the AsyncIterator pattern, and the structure of received data.
• Block Range Parameters: Understand how to define start_from and read_until.
• Browser Usage: Specific instructions for integrating the client in web browsers.
• Error Handling: Best practices for managing errors and disconnections.