ADR-012: Direct Method Calls Between Contexts¶

Status: IMPLEMENTED - 2025-01-15

Context¶

Need integration strategy between bounded contexts. Full version will use event-driven architecture.

Decision¶

Use direct method calls between contexts (synchronous).

Rationale¶

Simplest approach: No message bus, no events
Synchronous workflow: Matches file-based processing
Easy debugging: Clear call chain
Fast development: Minimal infrastructure

Alternatives Considered¶

Direct calls ✅ Chosen
Event bus: Too complex for MVP
Message queue: Infrastructure overhead
REST API: Unnecessary for single process

Implementation in MVP¶

Direct Integration Pattern¶

# main.py - Synchronous context calls
def main():
    # Direct method call to Configuration Context
    scenario = scenario_service.load_and_validate_scenario(config_path)

    # Direct instantiation with Workshop Operations Context
    orchestrator = WorkshopOrchestrator(sim, scenario)
    orchestrator.run()

    # Direct method call to Analytics Context
    metrics = orchestrator.get_metrics()
    kpis = kpi_calculator.calculate_all_kpis(metrics)

    # Direct call to export results
    exporter.export_results(kpis, output_path)

Interface Preparation¶

# Interfaces prepared for future event-driven migration
class ScenarioServiceInterface(ABC):
    @abstractmethod
    def load_and_validate_scenario(self, source: Path) -> Scenario: ...

class KPICalculatorInterface(ABC):
    @abstractmethod
    def calculate_all_kpis(self, metrics: SimulationMetrics) -> AllKPIs: ...

Consequences¶

Achieved¶

✅ Fast Development: No message bus or event infrastructure needed
✅ Easy Debugging: Clear call stack, simple error tracing
✅ Synchronous Flow: Matches file-based processing workflow
✅ Interface Ready: Abstract interfaces prepared for future migration
✅ Simple Testing: Direct method calls easy to test

Files Implementing This Decision¶

main.py - Direct context coordination
Context interfaces prepared for future event-driven architecture