Design Fault Injection Test Suite for Health Monitor Service Dependency Failures

[temma02]

Description

Build a fault injection test suite for the health monitor service that simulates failures in monitored dependencies (database, Stellar network, Vercel, Stripe) and verifies correct health status reporting and alerting.

Requirements and Context

• Testing: Use the fault-injector.ts service to simulate dependency failures
• Coverage: Target apps/backend/src/services/health-monitor.service.ts
• Documentation: Document health check dependency graph

Suggested Execution

Branch: test/issue-044-health-monitor-fault-injection-tests

Implement Changes

• Add fault injection tests simulating each monitored dependency failing
• Assert that the health monitor reports degraded/unhealthy status correctly
• Test partial failure scenarios (one dependency down, others healthy)
• Verify health status aggregation logic across all dependencies

Test and Commit

• Cover failure of each monitored dependency individually and in combination
• Assert correct aggregate health status for each scenario
• Document the dependency graph in service JSDoc

Example Commit Message

test(health-monitor): add fault injection suite for dependency failures

- Simulate failures for database, Stellar, Vercel, and Stripe
- Test partial failure scenarios
- Assert correct aggregate health status reporting

Guidelines

• Use the existing fault-injector service for consistency
• Test both individual and combined dependency failures
• Assert health status, not just exception handling

[Mystery-CLI]

@Mystery-CLI has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

i would like to work on this issue

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[drips-wave]

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