[Wave 6 4/10] Coordinator API contract tests for orders, quotes, secrets, health, and metrics

[karagozemin]

Summary

Add coordinator API contract tests for orders, quotes, secrets, health, and metrics routes so the public service surface is guarded before mainnet hardening.

Context

• Coordinator currently has service-level tests in coordinator/test/order-service.test.ts.
• Route handlers under coordinator/src/server/routes/ expose the API consumed by the frontend/resolvers, but route-level regression coverage is thin.
• Recent observability work added /metrics; that endpoint should stay valid Prometheus text as handlers evolve.

Scope

• Add Supertest/Vitest route tests against the Express app without starting a real network port.
• Cover success and validation-error paths for order creation/listing, quote responses, secret relay behavior, /health, and /metrics.
• Keep tests independent of live RPCs and external services.

Acceptance criteria

• pnpm --filter @oversync/coordinator test includes route-level API coverage.
• /health returns stable service/version/uptime/timestamp fields.
• /metrics returns Prometheus content type and includes coordinator metric names.
• Invalid order/quote payloads return 4xx with useful error bodies.

Pointers

• coordinator/src/server/app.ts
• coordinator/src/server/routes/health.ts
• coordinator/src/server/routes/metrics.ts
• coordinator/src/server/routes/orders.ts
• coordinator/src/server/routes/quotes.ts
• coordinator/src/server/routes/secrets.ts
• coordinator/test/order-service.test.ts

Complexity

Medium (API tests + validation edge cases)

[BuddiBisong]

@BuddiBisong has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

i can work on this issue because i have the right qualifications to solve the problem

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[drips-wave]

Congratulations, @BuddiBisong! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @BuddiBisong: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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