Gating billable actions - Jaza Docs

JazaActionButton answers one UX question: does this wallet have enough credits for featureCode? It never debits the wallet. Your host must call jaza.consume after a successful gate.

Attackers can bypass UI. Treat ActionButton as a convenience, not authorization. Always meter on the server.

Dual-SDK pattern

Layer	Responsibility
Expo	`JazaActionButton` compares balance to the feature cost from the session / features snapshot
Insufficient	Opens the top-up (paywall) sheet; does not run `onPress`
Sufficient	Runs your `onPress` → call your BFF
Node BFF	`jaza.consume({ customerId, featureCode, idempotencyKey })` with the secret key

Mobile

import { JazaActionButton } from '@jazadev/react-native';

const API_BASE = process.env.EXPO_PUBLIC_API_URL!;

<JazaActionButton
  featureCode="SEND_MESSAGE"
  label="Send message"
  onPress={async () => {
    const res = await fetch(`${API_BASE}/api/messages`, {
      method: 'POST',
      credentials: 'include',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ text: 'Hello' }),
    });
    if (!res.ok) throw new Error('Send failed');
  }}
/>

Configure SEND_MESSAGE (code + credit cost) in the dashboard under Features. Costs are included in the jaza.init snapshot and refreshed on the client. Optional children render props let you keep your own button styling while reusing the gate.

Host consume

// Inside POST /api/messages (after your auth + business logic)
await jaza.consume({
  customerId: req.user.jazaCustomerId,
  featureCode: 'SEND_MESSAGE',
  idempotencyKey: `msg_${messageId}`,
});

Handle insufficient credits on the server even if the UI already gated — the balance can change between tap and request. See Consume credits. When consume fails for insufficient credits, Jaza can also notify the mobile session over the client realtime channel so the SDK can open the paywall. You still return an error from your BFF.

What not to do

Do not call jaza.consume from the React Native app
Do not invent client-side “debit” endpoints that only trust the device
Do not use Fuel* or other unofficial component names — use JazaActionButton