The Account Lookup Service (ALS) (refer to section 6.2.1.2) as per the Mojaloop Specification implements the following use-cases:
Participant Look-up
Party Look-up
Manage Participants Registry information
Adding Participant Registry information
Deleting Participant Registry information
Use-cases that have been implemented over and above for Hub Operational use:
Admin Operations
Manage Oracle End-point Routing information
Manage Switch End-point Routing information
1. Design Considerations
1.1. Account Lookup Service (ALS)
The ALS design provides a generic Central-Service component as part of the core Mojaloop. The purpose of this component is to provide routing and alignment to the Mojaloop API Specification. This component will support multiple Look-up registries (Oracles). This ALS will provide an Admin API to configure routing/config for each of the Oracles similiar to the Central-Service API for the End-point configuration for DFSP routing by the Notification-Handler (ML-API-Adapter Component). The ALS will in all intense purpose be a switch with a persistence store for the storage/management of the routing rules/config.
1.1.1. Assumptions
The ALS design will only cater for a single switch for the time being.
Support for multiple switches will utilise the same DNS resolution mechanism that is being developed for the Cross Border/Network design.
1.1.2. Routing
The routing configuration will be based on the following:
PartyIdType - See section 7.5.6 of the Mojaloop Specification
Currency - See section 7.5.5 of the Mojaloop Specification. Currency code defined in ISO 4217 as three-letter alphabetic string. This will be optional, however isDefault indicator must be set to true if the Currency is not provided.
isDefault - Indicator that a specific Oracle is the default provider for a specific PartyIdType. Note that there can be many default Oracles, but there can only be a single Oracle default for a specific PartyIdType. The default Oracle for a specific PartyIdType will only be selected if the originating request does not include a Currency filter.
1.2. ALS Oracle
The ALS Oracle be implemented as either a Service or Adapter (semantic dependant on use - Mediation = Adapter, Service = Implementation) will provide a look-up registry component with similar functionality of the /participants Mojaloop API resources. It has however loosely based on the ML API specification as it's interface implements a sync pattern which reduces the correlation/persistence requirements of the Async Callback pattern implemented directly by the ML API Spec. This will provide all ALS Oracle Services/Adapters with a standard interface which will be mediated by the ALS based on its routing configuration.
This component (or back-end systems) will also be responsible for the persistence & defaulting of the Participant details.
2. Participant Lookup Design
2.1. Architecture overview
Architecture Flow Account-Lookup for Participants
Note: The Participant Lookup use-case similarly applies to for a Payee Initiated use-case such as transactionRequests. The difference being that the Payee is the initiation in the above diagram.
currency - See section 7.5.5 of the Mojaloop Specification. Currency code defined in ISO 4217 as three-letter alphabetic string. This will be optional, and must provide a "default" config if no Currency is either provided or provide a default if the Currency is provided, but only the "default" End-point config exists.
endPointType - Type identifier for the end-point (e.g. URL) which provides flexibility for future transport support.
migration* - Meta-data tables used by Knex Framework engine.
A centralSwitchEndpoint must be associated to the OracleEndpoint by the Admin API upon insertion of a new OracleEndpoint record. If the centralSwitchEndpoint is not provided as part of the API Request, then it must be defaulted.
