In order to receive callbacks about status changes for an invoice a callback URL must be specified first. But before setting your callback URL you must choose prefered authentication method which we will use for authenticating our requests when calling your callback URL. Currently we support Basic and ApiKey authentication methods:

Basic

PUT /api/v1/merchants/{merchantId}/auth/basic

{"username":"Username","password":"MySecretPswd","callback_url":"https://your.url/callbacks/invoice"}

ApiKey

PUT /api/v1/merchants/{merchantId}/auth/apikey

{"api_key":"SomeSecretApiKey123","callback_url":"https://your.url/callbacks/invoice"}

 Using ApiKey authentication method your provided API key will be simply added to Authorizationheader.