Testing and Verification

Testing & Verification Strategy

The Emporia Trading Platform employs a multi-layered verification strategy combining automated unit tests, integration tests with real databases, deterministic concurrency schedulers, and static code quality enforcement.

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🧪 Verification Matrix

Layer	Tools & Frameworks	Target & Purpose	Verification Command
Unit & Mock Testing	JUnit 5, Mockito, AssertJ	Individual business logic, records, state machines	mvn test
Code Coverage	JaCoCo (0.8.15)	Enforcement of 91.95%+ instruction & branch coverage	mvn verify
Database Concurrency	Testcontainers, PostgreSQL	Pessimistic vs Optimistic locking under parallel transactions	mvn test -Dtest=*PostgresConcurrencySpec
Controlled Concurrency	Fray Scheduler (0.9.0)	Controlled JVM thread interleavings (200 iterations, 170 timelines)	mvn -Pfray -pl order-management-service -am test
Static Code Quality	PMD (7.26.0), Custom Ruleset	Code correctness, resource management, exception handling	mvn pmd:check

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🔬 Multi-Layered Testing Details

1. JaCoCo Code Coverage Standard

• Every microservice defines a strict JaCoCo enforcement profile requiring minimum 90% instruction and branch coverage.
• Excludes auto-generated Protocol Buffers / gRPC classes and FIX protocol models.

# Run test suite with JaCoCo coverage reports across all 9 modules
mvn clean verify

2. Database Concurrency Testing (Testcontainers)

• Specification: TradingOrderPostgresConcurrencySpec in order-management-service.
• Purpose: Spawns ephemeral PostgreSQL instances via Testcontainers to verify JPA @Version optimistic locking and SQL pessimistic write locks under heavy concurrent transaction load.

3. Fray Deterministic Thread Scheduling

• Specification: TradingOrderFraySpec in order-management-service.
• Purpose: Uses Fray's byte-code instrumentation to explore 200 distinct thread interleavings between simultaneous applyFill and cancel executions on shared TradingOrder entities.

# Run Fray controlled thread scheduling specification
mvn -Pfray -pl order-management-service -am test

4. PMD Static Analysis Enforcement

• Ruleset: static-analysis/ruleset.xml.
• Enforces:
  • Proper exception catching (no swallowed exceptions).
  • Explicit resource cleanup (try-with-resources).
  • Clean concurrency primitives.
  • Zero violation tolerance (pmd.failOnViolation=true).

# Run PMD static code check
mvn pmd:check -Dpmd.failOnViolation=true