Subscriptions

const response = await fetch('https://checkout-api.exodus-int.com/subscription-checkouts', {
  method: 'POST',
  headers: {
    Authorization: 'Bearer sk_test_xxxxxxxxxxxxxxxx',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    token_symbol: 'USDC', // settlement token the subscriber pays in
    price: '9990000', // $9.99 USDC (6 decimals); omit price_currency = token-denominated
    recommended_cap: '120000000', // suggested cap (the subscriber sets the on-chain cap when signing)
    period_duration: 2592000, // 30 days in seconds
    supported_chains: ['eip155:1', 'eip155:137'], // CAIP-2 ids the subscriber picks from at sign time
    external_customer_id: 'cus_42',
    success_url: 'https://yoursite.com/welcome',
    cancel_url: 'https://yoursite.com/pricing',
    metadata: { external_plan_ref: 'pro_monthly' },
  }),
})
 
const intent = await response.json()
// Redirect your customer to intent.hosted_url
console.log(intent.hosted_url) // https://checkout.exodus-int.com/subscribe/schk_...

// After receiving the hosted URL from your server
window.location.href = hostedUrl

import express from 'express'
import crypto from 'crypto'
 
const app = express()
 
// Use express.raw() so we can verify the signature over the unparsed body
app.post('/webhooks/payments', express.raw({ type: 'application/json' }), (req, res) => {
  const expectedSignature = crypto
    .createHmac('sha256', process.env.WEBHOOK_SECRET)
    .update(req.body)
    .digest('hex')
 
  // Constant-time compare; normalize the header to a string first
  const received = Buffer.from(String(req.headers['x-signature'] ?? ''))
  const expectedBuffer = Buffer.from(expectedSignature)
  if (received.length !== expectedBuffer.length || !crypto.timingSafeEqual(received, expectedBuffer)) {
    return res.status(401).send('Invalid signature')
  }
 
  const event = JSON.parse(req.body)
 
  switch (event.type) {
    case 'subscription_checkout.completed': {
      // Customer subscribed AND the first charge cleared on-chain.
      // Payload bundles the intent, the subscription, and the first charge.
      const { object: intent, subscription, first_charge } = event.data
      console.log('Subscription started:', subscription.id)
      // Grant access, keyed on intent.external_customer_id ("cus_42")
      break
    }
    case 'subscription.charged': {
      const charge = event.data.object
      if (charge.status === 'succeeded') {
        console.log('Cycle charge succeeded:', charge.id)
      } else {
        // On a failed attempt, `failure_reason` is a typed contract error
        // (e.g., "InsufficientBalance"). Drive your dunning flow from here.
        console.log('Cycle charge failed:', charge.id, charge.failure_reason)
      }
      break
    }
    case 'subscription.cancelled': {
      console.log('Subscription cancelled:', event.data.object.id)
      // Revoke access
      break
    }
  }
 
  res.status(200).send('OK')
})
 
app.listen(3000)

import { signCharge } from '@exodus/checkout-signer/evm'
import { signingKeysFromMnemonic } from '@exodus/checkout-signer'
 
const headers = { Authorization: `Bearer ${process.env.API_KEY}` }
const { privateKey } = signingKeysFromMnemonic(process.env.SIGNING_MNEMONIC).evm
 
// The subscription's on-chain id, from the subscription_checkout.completed webhook
const subscriptionId = '0x9f3a2b...'
 
// Read the latest nonce & on-chain ids from the subscription
const sub = await fetch(`https://checkout-api.exodus-int.com/subscriptions/${subscriptionId}`, {
  headers,
}).then((r) => r.json())
 
// Quote the per-cycle amount (fixed price for token plans, a live FX quote for FIAT plans)
const quote = await fetch(`https://checkout-api.exodus-int.com/subscriptions/${sub.id}/charge-quote`, {
  method: 'POST',
  headers,
}).then((r) => r.json())
 
const signature = signCharge(
  sub.id,
  quote.amount,
  sub.charge_nonce,
  sub.subscription_manager_address,
  sub.chain,
  privateKey,
)
 
await fetch(`https://checkout-api.exodus-int.com/subscriptions/${sub.id}/charge`, {
  method: 'POST',
  headers: { ...headers, 'Content-Type': 'application/json', 'X-Signature': signature },
  body: JSON.stringify({ amount: quote.amount }),
})