[P1] Create integration test suite

[sfloess]

Problem

Project has unit tests but no integration tests to verify component interaction.

Impact

• Severity: MEDIUM
• Category: Quality/Reliability
• Cannot verify end-to-end scenarios
• May miss integration bugs
• Lower confidence in releases

Missing Test Scenarios

Core Integration Tests

1. Application Lifecycle:

   • Deploy → Start → Stop → Undeploy (full cycle)
   • Deploy multiple apps with dependencies
   • Hot reload with state preservation

2. Resource Enforcement:

   • Application exceeds CPU quota → SHUTDOWN action
   • Application exceeds heap quota → enforcement
   • Multiple apps competing for resources

3. Messaging:

   • App A publishes, App B receives
   • Service registry across apps
   • Message ordering guarantees

4. REST API:

   • Deploy via API, verify running
   • Start/stop via API
   • Concurrent API requests

5. ClassLoader Isolation:

   • Two apps with conflicting dependencies
   • ClassLoader cleanup on undeploy (no memory leaks)

Recommended Framework

Use Testcontainers for isolated integration tests:

@Testcontainers
class ApplicationLifecycleIT {
    @Container
    static GenericContainer<?> platform = new GenericContainer<>("platform-java:latest");
    
    @Test
    void shouldDeployAndStartApplication() {
        // Test here
    }
}

Module Structure

Create new module:

jplatform-integration-tests/
├── pom.xml
└── src/test/java/
    └── org/flossware/jplatform/it/
        ├── ApplicationLifecycleIT.java
        ├── ResourceEnforcementIT.java
        └── MessagingIT.java

Priority

P1 - High - Should be created for v1.2 release.

CI/CD Integration

Run integration tests in separate workflow:

name: Integration Tests
on: [push, pull_request]
jobs:
  integration-tests:
    runs-on: ubuntu-latest
    steps:
      - run: mvn verify -Pintegration-tests