import * as dotenv from "dotenv";
dotenv.config();
// src/server-payment.ts
import { wrapFetchWithPayment, createSigner, Signer } from 'x402-fetch';
import { PaymentClient, PaymentClientConfig, PaymentInfo } from './types.js';
interface ServerPaymentConfig extends PaymentClientConfig {
signer: Signer;
}
export abstract class BasePaymentClient implements PaymentClient {
abstract fetch(url: string, options?: RequestInit): Promise<Response>;
protected extractPaymentInfo(response: Response): PaymentInfo | null {
const paymentHeader = response.headers.get('x-payment-response');
if (!paymentHeader) {
return null;
}
try {
const decoded = JSON.parse(atob(paymentHeader));
return {
amount: decoded.amount,
recipient: decoded.recipient,
signature: decoded.signature,
wallet: decoded.wallet,
};
} catch (error: any) {
throw new Error(
'PAYMENT_FAILED',
error
);
}
}
protected handleError(error: any, context: string): never {
if (error instanceof Error) {
throw error;
}
throw new Error(
'INTERNAL_ERROR',
error
);
}
}
export class ServerPaymentClient extends BasePaymentClient {
private fetchWithPayment!: (input: RequestInfo, init?: RequestInit) => Promise<Response>;
private initPromise: Promise<void>;
constructor(config: ServerPaymentConfig) {
super();
if (!config.signer) {
throw new Error(
'PAYMENT_FAILED'
);
}
this.initPromise = this.initialize(config);
}
private async initialize(config: ServerPaymentConfig): Promise<void> {
try {
this.fetchWithPayment = wrapFetchWithPayment(fetch, config.signer);
} catch (error: any) {
this.handleError(error, 'Failed to initialize server payment client');
}
}
async fetch(url: string, options?: RequestInit): Promise<Response> {
await this.initPromise;
try {
return await this.fetchWithPayment(url, options);
} catch (error: any) {
this.handleError(error, 'Server payment fetch failed');
}
}
}
