Saved, shareable multi-panel dashboards (table/line/bar/single-stat panels via gridstack + uPlot, global + per-panel time range, JSON export/import) and threshold/absence alert rules with an ok/pending/firing evaluator and webhook/Slack/PagerDuty delivery. - New /metadata component: Postgres control-plane store for dashboards, panels, notification targets, alert rules/state, and delivery log -- see docs/phase-3-dashboard-design.md for why ClickHouse's MergeTree family isn't a fit for this access pattern (needs real row-level locking and read-your-writes consistency). - api/internal/dashboards: dashboard/panel CRUD, pure -- panel query execution stays client-side, reusing the existing /query endpoint. - New /alerting service: rule/target CRUD, a ticker-driven evaluator (claim-then-evaluate concurrency control, transactional-outbox delivery, query errors and threshold zero-rows never coerced into a false transition) and webhook/Slack/PagerDuty delivery with retry/backoff. See docs/phase-3-alerting-design.md for the full state-machine design and the four correctness properties it implements. - web: /dashboards and /alerts UIs; cli: sentryctl dashboards/alerts list/get/apply, seeding a future Terraform provider's JSON contract. - hack/alert-load-test: 500 rules against real ClickHouse data, real measured results in docs/phase-3-runbook.md. Five real bugs found by actually running this against a live stack (documented in the runbook, not just fixed silently): a latent Phase 2 bug where ClickHouse rejected the timestamp format used for earliest=/latest= queries; a "now" literal token injected into query text; a GridStack/uPlot layout-timing race; JS's Date.parse being too lenient to use as a timestamp-detection heuristic; a rule's "enabled" field silently defaulting to false when omitted; and the evaluator's claim-batch-size and worker-pool-concurrency defaulting to the same value, causing 500 concurrently-due rules to take 125s to cycle through instead of the configured 60s.
alert-load-test
Seeds a realistic number of concurrent alert rules via /alerting's real
create API (not a direct DB insert) and measures whether the evaluator's
claim scheduling keeps up under load. See
/docs/phase-3-alerting-design.md's "Load-testing plan" and
/docs/phase-3-runbook.md for the methodology and real measured results.
# 1. Push real data so rule queries have real work to do (reuses
# hack/benchmark-fixture):
cd ../benchmark-fixture
go run . --count 500000
# 2. Run a webhook-sink so the (never-firing, by design) rules have a
# valid notification target to point at:
docker run -d --name sentry-webhook-sink --network sentry_default \
-p 9099:9099 -v $(pwd)/../webhook-sink:/src -w /src golang:1.25-alpine go run .
# 3. Run the load test:
cd ../alert-load-test
go run . --rule-count 500 --eval-interval-seconds 60 --duration 3m30s
Each rule queries a different host's count over the last minute
(earliest=-1m host="host-01" | stats count) against real ClickHouse
data, with threshold_value set unreachably high so rules stay ok --
this isolates evaluator/ClickHouse scheduling throughput from
delivery-worker load (a query that never fires still exercises the exact
same claim → /query → evaluate → ApplyTransition path every tick).
The report shows, per rule, the observed intervals between consecutive
last_evaluated_at changes (polled at --poll-interval), compared
against the configured eval_interval_seconds. A real, significant
finding from actually running this: the evaluator's claim batch size and
worker-pool concurrency limit defaulted to the same number (20), so 500
rules all due at once took 125s to cycle through instead of the
configured 60s. Fixed by separating EVALUATOR_CLAIM_BATCH_SIZE from
EVALUATOR_WORKER_POOL_SIZE (see alerting/internal/config/config.go).
Cleans up the seeded rules and notification target on exit unless
--no-cleanup is passed.