bcquality/custom/knowledge/architecture/pages-must-not-contain-business-logic.md
Michael Dieringer 288f64df16 Add BCApps citations to Tier 1+2 knowledge files; add 2 new rules
- All 7 existing Tier 1/2 knowledge files now include a BCApps Reference
  section with concrete source links and observed patterns
- New: bcpt-scenarios-must-be-app-specific — PerformanceTest apps must
  include app-domain BCPT scenarios, not only Microsoft generic samples
- New: permission-sets-must-follow-least-privilege — View/Edit/Admin
  hierarchy with IncludedPermissionSets, mirroring BCApps BusFound pattern
- api-page-key-fields-must-be-editable-on-insert clarified: SystemId as
  ODataKeyField + Editable=false is valid (auto-generated); rule applies
  to consumer-provided key fields only

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-06-23 17:48:37 +02:00

2.1 KiB

CURABIS Architecture: Page Presentation vs. Business Logic

Core Rule

In CURABIS codebases, pages serve exclusively as presentation layers. All business logic—including calculations, validations, and record modifications—must reside in codeunits, not in page triggers or actions. This standard is more rigorous than general Business Central guidance and applies uniformly across all CURABIS PTE applications.

Key Principle

"A page procedure that calculates a value and assigns it to a field, calls Rec.Modify() directly, or implements business rules is an architecture violation even if it compiles."

Permitted Exceptions

Two specific scenarios allow deviation from this rule:

  1. Setup Pages: May directly read and write their own setup records
  2. Conversion Pages: The designated "Run Conversion" page may invoke the conversion codeunit directly

Anti-Pattern Examples

Pages should not contain:

  • Direct calculations (e.g., Rec."Total Amount" := Rec.Quantity * Rec."Unit Price")
  • Calls to Rec.Modify() within page triggers
  • Business rule validation logic embedded in page triggers

Best Practice Implementation

Pages should delegate to codeunits for all business operations:

  • "The page owns the presentation" while "The codeunit owns the logic"
  • Use codeunit procedures (e.g., SVManagement.RecalculateLine(Rec)) for calculations and modifications
  • Route all validations through codeunits rather than page triggers

This separation ensures maintainability, testability, and consistency across CURABIS applications.

BCApps Reference

Microsoft's own BCApps repository confirms this pattern. In the Performance Toolkit, BCPTSetupCard.Page.al and BCPTSetupList.Page.al contain no business logic — all operations are delegated to BCPTStartTests.Codeunit.al and BCPTHeader.Codeunit.al. This is consistent across all BCApps pages.