@payweave/fastify

@payweave/fastify

Fastify plugin for PayWeave - accept per-request USD micropayments on any Fastify route.

Install

npm install @payweave/fastify

Quick Start

import { Payweave } from '@payweave/fastify';
import Fastify from 'fastify';

const app = Fastify();
const payweave = new Payweave(
  process.env.PAYWEAVE_APP_ID!,
  process.env.PAYWEAVE_APP_SECRET!
);

app.get(
  '/api/weather',
  { preHandler: payweave.charge({ price: '0.001', description: 'Weather API' }) },
  (req, reply) => {
    reply.send({ temp: 72, unit: 'F' });
  }
);

app.listen({ port: 3000 });

API

new Payweave(appId, appSecret, baseUrl?)

Parameter	Type	Description
appId	string	Your app key ID
appSecret	string	Your app secret
baseUrl	string?	API base URL (defaults to https://api.payweave.app)

payweave.charge(options)

Returns a Fastify preHandler hook (req: FastifyRequest, reply: FastifyReply) => Promise<void>.

Option	Type	Description
price	string | (req: FastifyRequest) => string | Promise<string>	USD price per request
description	string?	Human-readable description
meta	Record<string, string>?	API metadata for agent discovery

Note: Use payweave.charge() as a preHandler in Fastify's route options.

Examples

Static pricing

app.get(
  '/api/search',
  { preHandler: payweave.charge({ price: '0.01' }) },
  (req, reply) => {
    reply.send({ results: [] });
  }
);

Dynamic pricing

app.post(
  '/api/generate',
  {
    preHandler: payweave.charge({
      price: (req) => {
        const body = req.body as { premium?: boolean };
        return body.premium ? '0.05' : '0.01';
      },
      description: 'Text generation',
    }),
  },
  (req, reply) => {
    reply.send({ text: 'generated content' });
  }
);

Multiple preHandlers

app.post(
  '/api/data',
  {
    preHandler: [
      authenticate,
      payweave.charge({ price: '0.01' }),
    ],
  },
  (req, reply) => {
    reply.send({ data: 'paid content' });
  }
);

With metadata for agent discovery

app.post(
  '/api/sentiment',
  {
    preHandler: payweave.charge({
      price: '0.005',
      description: 'Sentiment analysis',
      meta: {
        'method': 'POST',
        'input.content-type': 'application/json',
        'input.schema': '{"type":"object","properties":{"text":{"type":"string"}}}',
        'output.schema': '{"type":"object","properties":{"score":{"type":"number"}}}',
      },
    }),
  },
  (req, reply) => {
    reply.send({ score: 0.85 });
  }
);

Multiple routes

app.get('/api/weather', { preHandler: payweave.charge({ price: '0.001' }) }, weatherHandler);
app.get('/api/forecast', { preHandler: payweave.charge({ price: '0.005' }) }, forecastHandler);
app.post('/api/analyze', { preHandler: payweave.charge({ price: '0.01' }) }, analyzeHandler);

How It Works

• A request hits your route without a payment header
• The preHandler responds with 402 Payment Required and pricing info
• The agent submits payment on Tempo and retries with Authorization: Payment <credential>
• PayWeave verifies the payment and sets a Payment-Receipt header
• Your handler executes normally

License

MIT