Gradium.js

A JavaScript library for fetching detailed block information from Polkadot-based blockchains.

Installation

npm install gradium-js

Usage

import { Gradium } from 'gradium-js';

async function main() {
    // Initialize the Gradium client
    const gradium = new Gradium('wss://rpc.polkadot.io');
    await gradium.init();

    try {
        // Fetch block information using a block hash
        const blockInfo = await gradium.fetchBlockInfo('0x123...'); // Replace with actual block hash
        
        console.log('Block Number:', blockInfo.number);
        console.log('Block Hash:', blockInfo.hash);
        console.log('Timestamp:', blockInfo.timestamp);
        
        // Access extrinsics
        blockInfo.extrinsics.forEach(ext => {
            console.log(`Extrinsic: ${ext.section}.${ext.method}`);
        });
        
        // Access events
        blockInfo.events.forEach(event => {
            console.log(`Event: ${event.section}.${event.method}`);
        });
    } catch (error) {
        console.error('Error:', error);
    }
}

API Reference

Gradium Class

Constructor

constructor(wsUrl: string)

Creates a new Gradium instance with the specified WebSocket URL.

Methods

• init(): Promise<void> - Initializes the connection to the blockchain
• fetchBlockInfo(hash: string): Promise<BlockInfo> - Fetches detailed block information
• fetchFinalizedHead(): Promise<Hash> - Gets the latest finalized block hash
• fetchHeader(hash: string): Promise<Header> - Fetches block header
• fetchBlockHash(number: number): Promise<Hash> - Gets block hash by number
• fetchBlock(hash: string): Promise<Block> - Fetches raw block data
• fetchCurrentSetId(atHash: string): Promise<string> - Gets current GRANDPA set ID
• fetchAuthorities(atHash: string): Promise<any> - Fetches GRANDPA authorities
• hashSha3(data: string): string - Computes SHA3 hash of input data

Block Information Structure

{
    hash: string;          // Block hash
    number: number;        // Block number
    parentHash: string;    // Parent block hash
    stateRoot: string;     // State root hash
    extrinsicsRoot: string;// Extrinsics root hash
    timestamp: number;     // Block timestamp
    extrinsics: [         // Array of extrinsics
        {
            index: number;
            section: string;
            method: string;
            signer: string | null;
            nonce: number | null;
            isSigned: boolean;
            tip: number | null;
        }
    ];
    events: [             // Array of events
        {
            index: number;
            section: string;
            method: string;
            phase: string;
            data: any;
        }
    ];
}

Development

1. Clone the repository
2. Install dependencies: npm install
3. Build the project: npm run build

License

MIT