API integration

To communicate with Payment Manager, DFSPs are required to implement Core Connector in alignment with their backend technology so that their backend can talk to the Payment Manager API. To help API implementation efforts, DFSPs are provided with:

  • the specification of the Payment Manager API

  • a Core Connector template

What is a Core Connector template? DFSP Core Backends have their own custom API or enterprise integration solutions so multiple variants of Core Connector have been built to align with common Core Banking Solution (CBS) products. These Core Connector variants are all built using a standard template. The template provides a placeholder codebase for the API endpoints that need to be developed.

The effort for a DFSP to customise a Core Connector template will differ depending on the chosen deployment option. When deploying Payment Manager, two options are available:

  • Hosted by System Integrator: The System Integrator deploys Payment Manager in the cloud, and syncs up the Core Connector template with the DFSP’s core backend implementation.

  • Self-hosted by DFSP: The DFSP deploys Payment Manager on premise or in the cloud, and the customisation of the Core Connector template can be done by a number of actors (depending on the outcome of an initial assessment of DFSP capabilities):

    • by the System Integrator

    • by the System Integrator and the vendor of the DFSP’s core backend solution (in close collaboration)

    • by the DFSP and the vendor of the DFSP’s core backend solution (in close collaboration)

This document focuses on Payment Manager API, the API at the back of Core Connector. Payment Manager API is a Mojaloop-centric API built around the resource types of the Mojaloop FSPIOP API but applying a use-case-oriented approach. The key resources of the Mojaloop FSPIOP API are the party lookup, quotes, and transfers services:

  • Party lookup service: Identifying the DFSP serving the Payee and the Payee itself (= the recipient of funds in a transaction) based on a Payee identifier (typically a MSISDN, that is, a mobile number).

  • Quotes service: Requesting a quote and exchanging cryptographic proof to prepare and secure the transfer. A quote is a contract between a Payer DFSP and Payee DFSP for a particular financial transaction before the transaction is performed. It guarantees the agreement set by the Payer and Payee DFSPs about the Payer, the Payee, and transfer amount, and is valid during the lifetime of a quote and transfer of a specified financial transaction.

  • Transfers service: Executing the transaction as per the agreed details and cryptographic proof.

Within the context of the Mojaloop FSPIOP API, the transfer happens in three main steps corresponding to these three phases:

  1. Identifying the Payee (party lookup or discovery phase)

  2. Agreeing the transfer (quote or agreement phase)

  3. Executing the transfer (transfer phase)

Using Payment Manager and the Payment Manager API, the DFSP has the choice to perform the transfer process in one combined step, in two steps, or three steps.

For more information on the three phases of a transfer in Mojaloop, see Module 2: Mojaloop in greater detail of Mojaloop training course DFSP-101.

The next sections look at details of the Payment Manager API that DFSPs are required to interact with via the Core Connector, whether in a Payer DFSP or a Payee DFSP role.