nodejs-cryptomus/src/services/webhook.ts

A comprehensive Node.js client for the Cryptomus API

import { WebhookPayload, PaymentWebhookPayload, PayoutWebhookPayload } from '../types';
import { verifyWebhookSignature } from '../utils/signature';

/**
 * Webhook service for handling and validating webhooks
 */
export class WebhookService {
  private readonly apiKey: string;

  /**
   * Create a new webhook service
   * 
   * @param apiKey - API key for signature verification
   */
  constructor(apiKey: string) {
    this.apiKey = apiKey;
  }

  /**
   * Parse and validate a webhook payload
   * 
   * @param payload - Raw webhook payload as string
   * @param signature - Signature from webhook headers
   * @returns Parsed webhook payload
   * @throws Error if signature is invalid
   */
  parseWebhook(payload: string, signature: string): WebhookPayload {
    if (!verifyWebhookSignature(payload, signature, this.apiKey)) {
      throw new Error('Invalid webhook signature');
    }
    
    const parsedPayload = JSON.parse(payload) as WebhookPayload;
    return parsedPayload;
  }

  /**
   * Parse and validate a payment webhook payload
   * 
   * @param payload - Raw webhook payload as string
   * @param signature - Signature from webhook headers
   * @returns Parsed payment webhook payload
   * @throws Error if signature is invalid or payload type is not payment
   */
  parsePaymentWebhook(payload: string, signature: string): PaymentWebhookPayload {
    const parsedPayload = this.parseWebhook(payload, signature);
    
    if (parsedPayload.type !== 'payment') {
      throw new Error('Invalid webhook type, expected payment webhook');
    }
    
    return parsedPayload as PaymentWebhookPayload;
  }

  /**
   * Parse and validate a payout webhook payload
   * 
   * @param payload - Raw webhook payload as string
   * @param signature - Signature from webhook headers
   * @returns Parsed payout webhook payload
   * @throws Error if signature is invalid or payload type is not payout
   */
  parsePayoutWebhook(payload: string, signature: string): PayoutWebhookPayload {
    const parsedPayload = this.parseWebhook(payload, signature);
    
    if (parsedPayload.type !== 'payout') {
      throw new Error('Invalid webhook type, expected payout webhook');
    }
    
    return parsedPayload as PayoutWebhookPayload;
  }
}