Investigate Feasibility of Splitting Tight-Coupling in Notes Client Applications

In application development beyond Domino, the preference has been for looser coupling. In Notes Client there is a lot of tight coupling. Composite Applications aimed to address this, but they were complex, tied to Eclipse, and crucially required hard-codings between NSFs that were tied to implementation and environment.

• Forms are tied to documents in a 1-1 relationship, although form formulas and computed subforms give some flexibility for the UI layer to be manipulated. (A little creativity is needed for rich text fields!)
• Forms cannot easily display a document from another database.
• Embedded views can be pointed to a different database, but database B cannot be defined programmatically. This is required to handle different environments.
• Outline entries can also pick from a different database, but not programmatically.

This means that although applications can be split into multiple databases:

1. Each database's UI resides in the same database as the design
2. Shared code needs copying and maintaining across multiple databases
3. Workspace icons get added for all databases

Many XPages developers have moved to having a UI NSF and data database(s). For Java or JavaScript developers, looser coupling is standard.

Having the UI and business logic in a separate database would also make sense in the context of LotusScript REST services, to have all your REST services in a single NSF and re-using client business logic, while restricting web access to all the data NSFs.