API Reference

Authentication

The OneLinkFintech API uses API keys to authenticate requests. You can view and manage your API keys in the Dashboard.

API Keys

Include your API key in all API requests to the server in an Authorization header:

Authorization: Bearer YOUR_API_KEY

Testing with Sandbox

Use our sandbox environment for testing with test API keys and mock data:

https://api.sandbox.onelinkfintech.com/v1

Production Environment

https://api.onelinkfintech.com/v1

Quick Start

Make your first API request to create a test payment in the sandbox environment:

curl -X POST https://api.sandbox.onelinkfintech.com/v1/payments \
  -H "Authorization: Bearer YOUR_SANDBOX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "amount": 1000,
    "currency": "EUR",
    "recipient": "rec_test_123",
    "description": "Test Payment"
  }'

const fetch = require('node-fetch');

const response = await fetch('https://api.sandbox.onelinkfintech.com/v1/payments', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_SANDBOX_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    amount: 1000,
    currency: 'EUR',
    recipient: 'rec_test_123',
    description: 'Test Payment'
  })
});

const data = await response.json();
console.log(data);

import requests

url = "https://api.sandbox.onelinkfintech.com/v1/payments"
headers = {
    "Authorization": "Bearer YOUR_SANDBOX_API_KEY",
    "Content-Type": "application/json"
}
data = {
    "amount": 1000,
    "currency": "EUR",
    "recipient": "rec_test_123",
    "description": "Test Payment"
}

response = requests.post(url, headers=headers, json=data)
print(response.json())

Example Response

{
  "id": "pay_123456789",
  "object": "payment",
  "amount": 1000,
  "currency": "EUR",
  "status": "pending",
  "recipient": "rec_test_123",
  "description": "Test Payment",
  "created_at": "2025-01-01T12:00:00Z",
  "updated_at": "2025-01-01T12:00:00Z"
}

Accounts

Create and manage financial accounts for your users.

Create a new account for a user.

Request Body

Example Request

POST /v1/accounts
Authorization: Bearer YOUR_API_KEY
Content-Type: application/json

{
  "currency": "EUR",
  "owner": {
    "name": "John Doe",
    "email": "john@example.com"
  },
  "metadata": {
    "internal_id": "12345"
  }
}

Example Response

{
  "id": "acc_123456789",
  "object": "account",
  "currency": "EUR",
  "balance": 0,
  "status": "active",
  "owner": {
    "name": "John Doe",
    "email": "john@example.com"
  },
  "iban": "DE89370400440532013000",
  "created_at": "2025-01-01T12:00:00Z",
  "updated_at": "2025-01-01T12:00:00Z"
}

Retrieve an account by its ID.

Example Request

GET /v1/accounts/acc_123456789
Authorization: Bearer YOUR_API_KEY

Payments

Create and manage payments between accounts.

Create a new payment.

Request Body

Example Response

{
  "id": "pay_987654321",
  "object": "payment",
  "amount": 1000,
  "currency": "EUR",
  "status": "processing",
  "sender": "acc_123456789",
  "recipient": "rec_test_123",
  "description": "Test Payment",
  "created_at": "2025-01-01T12:05:00Z",
  "updated_at": "2025-01-01T12:05:00Z"
}

Errors

The OneLinkFintech API uses conventional HTTP response codes to indicate success or failure of an API request.

HTTP Status Codes

Error Response Format

{
  "error": {
    "code": "invalid_request",
    "message": "Amount must be a positive integer",
    "param": "amount",
    "type": "invalid_parameter"
  }
}