Add Prometheus /metrics endpoint

[Miracle656]

Background

Wraith runs as a persistent background service but exposes no operational metrics. When the indexer stalls or RPC calls start failing, there is no automated way to detect it. A Prometheus /metrics endpoint enables dashboards and automated alerting.

What to build

Add GET /metrics exposing Prometheus counters and gauges: ledgers indexed, transfers stored, RPC errors, last indexed ledger, DB query latency.

Key files

• src/server.ts — register the metrics route
• src/metrics.ts — create this module using prom-client
• src/indexer.ts — increment counters here

Suggested execution

git checkout -b feat/prometheus-metrics

1. npm install prom-client
2. Create src/metrics.ts — define: ledgers_indexed_total (counter), transfers_stored_total (counter), rpc_errors_total (counter), last_indexed_ledger (gauge), db_query_duration_seconds (histogram)
3. Instrument the indexer loop and route handlers
4. Register GET /metrics returning Prometheus text format
5. Update /status to include last_indexed_ledger as JSON

Example commit message:
feat(indexer): add Prometheus /metrics endpoint with indexer and transfer counters

Acceptance criteria

• GET /metrics returns valid Prometheus text format
• At least 4 custom metrics exported
• /status updated to include last_indexed_ledger

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Drips Wave · Complexity: Medium · 150 points
Comment below to request assignment. PR must include Closes #[this issue].

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[amina69]

@amina69 has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

hi, let me work on this

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[drips-wave]

Congratulations, @amina69! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on April 29, 2026.

🧑‍💻 @amina69: 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.

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[Ebomi]

@Ebomi has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi Maintainer. Please allow me to work on this

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[royalTreasure]

@royalTreasure has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I would like to work on this issue. I will create src/metrics.ts using prom-client to define all five specified metrics including the ledgers_indexed_total and transfers_stored_total counters, the rpc_errors_total counter, the last_indexed_ledger gauge, and the db_query_duration_seconds histogram, then instrument the indexer loop and route handlers in indexer.ts to increment them at the right points in the execution path. I will register GET /metrics in server.ts returning valid Prometheus text format and update the /status endpoint to include last_indexed_ledger as a JSON field so both monitoring systems and quick human checks have access to the current indexer position. I will verify the metrics output is correctly formatted and that all five custom metrics appear with meaningful values after a short indexing run before submitting. Can I be assigned?

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