Add configurable slow-query logging around Postgres pool queries in src/db/index.ts

[Jagadeeshftw]

Description

src/db/index.ts exposes getPoolStats and a basic checkDbHealth probe, but individual queries executed through the shared pool/db handle are not timed, so a slow query on payments, agreementEvents, or escrowEvents is invisible until it manifests as request latency downstream. Add a lightweight wrapper that logs any query exceeding a configurable threshold with duration and a truncated, parameter-redacted SQL preview.

Requirements and context

• Add a DB_SLOW_QUERY_THRESHOLD_MS env var (default e.g. 500ms) to src/config.ts
• Wrap pool.query (or the Drizzle query logger hook) in src/db/index.ts to time each call and log a structured warning when the threshold is exceeded, reusing the existing console.warn/JSON logger from src/utils/logger.ts
• Never log raw parameter values that could contain PII or secrets — log parameter count/types only
• Must be secure, tested, and documented
• Should be efficient and easy to review

Suggested execution

Fork the repo and create a branch

git checkout -b feature/db-slow-query-logging

Implement changes

• Update/Write: src/db/index.ts
• Update/Write: src/config.ts
• Add/Update tests: src/db/health.test.ts
• Add documentation: docs/db/schema.md
• Include clear code comments and TS types
• Validate security assumptions

Test and commit

• Run tests: pnpm test
• Cover edge cases
• Include test output and security notes

Example commit message

feat: add slow-query logging to the Postgres pool

Guidelines

• Minimum 95 percent test coverage
• Clear documentation
• Timeframe: 96 hours

[Stephan-Thomas]

📋 Grainlify Application

@Stephan-Thomas has applied to work on this issue as part of the Grainlify program.

hi, i would like to work on this.

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[TS-mfon]

📋 Grainlify Application

@TS-mfon has applied to work on this issue as part of the Grainlify program.

GM

i'm a blockchain developer

please can i work on this issue

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[dotmantissa]

📋 Grainlify Application

@dotmantissa has applied to work on this issue as part of the Grainlify program.

Hi maintainers,

I'd like to work on this. I'll add DB_SLOW_QUERY_THRESHOLD_MS to config.ts, wrap the pool query handler in db/index.ts to time each call and emit a structured warning via the existing logger when the threshold is exceeded, log only parameter count and types never raw values, and document it in docs/db/schema.md with 95 percent test coverage.

I estimate I can have a PR ready within 3 hours of being assigned. Could you please assign this to me?

Thanks.

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Repo Maintainers: To accept this application, review their application or assign @dotmantissa to this issue.