All calls to Real-Time Loon must include the following API headers:

HeaderFormatExampleDescription
X-DateUTC timestamp in ISO 8601 format2022-07-28T16:05:32.00Z with optional microseconds and ZThe date and time of the request
X-Client-Key32 character string538A4B83FEC409ECE24CE373A883A432 “data”The public ClientKey you obtained during onboarding
AuthorizationStringV1-HMAC-SHA256, Signature: Qj23jk3…(base64 encoded)What your code will generate when making the request
X-Merchant-IDString”9bb8592c-cb99-48f7-907e-f97de930fc5c”Identifies the merchant making the request

The first three headers are used for authentication, and the x-merchant-ID clarifies which merchant sent the request. This merchant identification is especially important for platform providers; learn more below .

Real-Time Loon Authentication

When you make a call to Real-Time Loon, you’re requesting and receiving critical payment credentials and secure data for your customers. As such, we have gone beyond the simple API key approach to authentication and instead leverage a common HTTP REST-API pattern (AWS, Docusign, etc.) based on a keyed-HMAC (Hash Message Authentication Code) for authentication.

This guide outlines how a developer authenticates and proves their identity to access the Real-Time Loon service.

Authentication Credentials

When you first log into the Real-Time Loon Service Panel, click Developers, then click API to locate the following API credentials:

  • Client Key (public)
  • Private Key

With every request you submit to Real-Time Loon, you must submit your public Client Key, along with a message signature that you generate using your public Client Key and your private Private Key combined with the request message itself. These details will be combined inside the HTTP headers as part of every request, as shown below.

Once Pagos receives a request, we’ll also calculate a signature; if they match, we’ll proceed with the request. Otherwise, an error will be returned and we’ll drop the request as not authorized.

Authentication Signature HTTP Headers

All calls to Loon must include an HMAC signature and at least these three headers:

HeaderFormatDescriptionExample
X-dateUTC timestamp in ISO 8601 formatThe date and time of the request2023-10-20T01:01:01.00Z (With optional microseconds and Z)
X-client-key32 character stringYour Client Key538A4B83FEC409ECE24CE373A883A432
AuthorizationStringThe Signature value will be generated using the Private Key at run time, after the account object is encryptedV1-HMAC-SHA256, Signature: Qj23jk3…(base64 encoded)

Authentication Signature Algorithm

The requester code will combine the following data elements to form a string, and then use an HMAC library to compute the sha256 digest in base64 format:

  • Client Key
  • Date
  • Request Body

The signature will be in the format of the following example:

signature = Base64 ( HmacSHA256 ( clientKey + date + requestBody\*\* ) );

Note:Ensure the the requestBody contains messages using the accountEncrypted key, and the value is the encrypted account object as described in the Real-Time Loon Encryption guide. Don’t send account details in plain text using the account key.

Merchant Identification

To better support Pagos users with merchant-to-platform hierarchies, Loon includes a x-merchant-ID attribute in the header that sits underneath the API User. The relationship between API User and merchant is 1..n; an API User can have n merchants but a merchant will be associated with only one API User. This merchant ID will be used in the Pagos system to pull the applicable network specific keys, MIDs, and TRIDs that Pagos sends to the networks for account updates.

We’ll assign this unique merchant ID to you at the time of onboarding. If your business doesn’t operate as a platform, you’ll always use the same ID in the header of each call.