import axios from "axios";
import { Config } from "../config.js";
export class EvmRpcClient {
private readonly rpcUrl: string;
private readonly chainName: string;
private chainId: number | null = null;
constructor(config: Config) {
this.rpcUrl = config.evmRpcUrl || "https://eth.llamarpc.com";
this.chainName = config.evmChainName || "Ethereum";
}
/**
* Makes a JSON-RPC call to the Ethereum endpoint
* @param method - The RPC method to call
* @param params - The parameters to pass to the method
* @returns The result of the RPC call
* @throws Error if the RPC call fails or returns an error
*/
async callRPC(method: string, params: any[]): Promise<any> {
if (!method) {
throw new Error("RPC method is required");
}
const payload = {
jsonrpc: "2.0",
id: Date.now(),
method,
params,
};
try {
const response = await axios.post(this.rpcUrl, payload);
if (response.data.error) {
const errorMessage = response.data.error.message || "Unknown RPC error";
throw new Error(`RPC Error: ${errorMessage}`);
}
return response.data.result;
} catch (error: any) {
const errorMessage = error.response?.data?.error?.message || error.message;
console.error(`Failed RPC call to "${method}":`, errorMessage);
error.rpcMethod = method;
error.rpcParams = params;
throw error;
}
}
/**
* Gets the chain ID from the Ethereum network
* @returns The chain ID as an integer
* @throws Error if the RPC call fails
*/
async getChainId(): Promise<number> {
if (this.chainId !== null) {
return this.chainId;
}
try {
const chainIdHex = await this.callRPC("eth_chainId", []);
const chainIdInt = parseInt(chainIdHex, 16);
console.log(`Chain ID: ${chainIdHex} (${chainIdInt} in decimal)`);
this.chainId = chainIdInt;
return chainIdInt;
} catch (error: unknown) {
const errorMessage =
error instanceof Error ? error.message : "Unknown error occurred";
console.error(`Failed to get chain ID: ${errorMessage}`);
throw error;
}
}
/**
* Validates the RPC URL by testing the connection
* @returns true if the connection is valid
* @throws Error if the connection fails
*/
async validateConnection(): Promise<boolean> {
console.log(`Validating Ethereum RPC URL: ${this.rpcUrl}`);
try {
// Test the connection with a simple eth_blockNumber call
const blockNumber = await this.callRPC("eth_blockNumber", []);
console.log(`✅ RPC endpoint is working. Current block number: ${blockNumber}`);
return true;
} catch (error: unknown) {
const errorMessage =
error instanceof Error ? error.message : "Unknown error occurred";
console.error(`❌ Failed to connect to RPC endpoint: ${errorMessage}`);
console.error(
"Please check that the URL is correct and the endpoint is accessible."
);
throw error;
}
}
/**
* Checks if the connected chain is Zircuit
* @returns true if the chain ID matches Zircuit
*/
async isZircuitChain(): Promise<boolean> {
const ZIRCUIT_CHAIN_ID = 48900;
const chainId = await this.getChainId();
return chainId === ZIRCUIT_CHAIN_ID;
}
/**
* Get the RPC URL
*/
getRpcUrl(): string {
return this.rpcUrl;
}
/**
* Get the chain name
*/
getChainName(): string {
return this.chainName;
}
}
