Fetch API

The @sapiom/fetch package creates a Sapiom-enabled fetch function with automatic payment handling and authorization.

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Installation

npm

npm install @sapiom/fetch

pnpm

pnpm add @sapiom/fetch

yarn

yarn add @sapiom/fetch

Note

No Dependencies: Uses native Fetch API available in Node.js 18+

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Basic Setup

Create a Sapiom-enabled fetch function:

import { createFetch } from '@sapiom/fetch';

const fetch = createFetch({
  apiKey: process.env.SAPIOM_API_KEY
});

// Drop-in replacement for native fetch
const response = await fetch('https://api.example.com/data');
const data = await response.json();

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Configuration

All configuration options for createFetch:

import { createFetch } from '@sapiom/fetch';

const fetch = createFetch({
  // Optional - Automatically uses process.env.SAPIOM_API_KEY if not provided
  apiKey: process.env.MY_CUSTOM_SAPIOM_KEY,

  // Optional - Control
  enabled: true,              // Enable Sapiom handling (default: true)
  failureMode: 'open',        // 'open' | 'closed' (default: 'open')
                              // 'open': Allow requests if Sapiom fails (prioritizes availability)
                              // 'closed': Block requests if Sapiom fails (prioritizes security)

  // Optional - Default metadata (applied to all requests)
  agentName: 'my-agent',      // Agent identifier
  agentId: 'agent-123',       // Agent UUID or numeric ID
  serviceName: 'my-service',  // Service name for transactions
  traceId: 'trace-xyz',       // Internal trace UUID
  traceExternalId: 'ext-456', // External trace identifier
});

Configuration Options

apiKey string required

Your Sapiom API key. Can also be set via SAPIOM_API_KEY environment variable

enabled boolean default: true

Enable Sapiom handling. When disabled, requests pass through without Sapiom processing

failureMode 'open' | 'closed' default: 'open'

Control behavior when Sapiom operations fail:

• 'open': Allow requests to proceed (prioritizes availability)
• 'closed': Block requests (prioritizes security)

agentName string

Agent identifier for tracking and attribution

agentId string | number

Agent UUID or numeric ID

serviceName string

Service name for transactions

traceId string

Internal trace UUID for request correlation

traceExternalId string

External trace identifier for integration with external systems

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Per-Request Overrides

Override configuration for individual requests using the __sapiom property:

// Disable Sapiom for a specific request
const publicRequest = new Request('/api/public');
(publicRequest as any).__sapiom = { enabled: false };
await fetch(publicRequest);

// Override metadata for a specific request
const request = new Request('/api/resource', { method: 'POST' });
(request as any).__sapiom = {
  serviceName: 'different-service',
  actionName: 'custom-action',
  traceExternalId: 'ext-789'
};
await fetch(request);

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Payment Handling

The wrapper automatically handles 402 Payment Required responses:

import { createFetch } from '@sapiom/fetch';

const fetch = createFetch({
  apiKey: process.env.SAPIOM_API_KEY
});

try {
  // Automatically handles 402 payment flows
  const response = await fetch('https://api.example.com/premium-endpoint');
  const data = await response.json();
  console.log(data);
} catch (error) {
  // Payment errors will be handled by Sapiom
  console.error('Request failed:', error);
}

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Environment Variables

Automatically reads from environment:

• SAPIOM_API_KEY (required)
• SAPIOM_BASE_URL or SAPIOM_API_URL (optional)
• SAPIOM_TIMEOUT (optional, in milliseconds)

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Next Steps

Axios Axios client integration

Node.js HTTP Native http/https integration