.nornir/collectors/polisen-events.md

Collector: `polisen-events` (adopted — WAVE 2, batch 6)

The Polisen incident-notice daemon. Fetches the Swedish Police public events API (https://polisen.se/api/events — a top-level JSON array, no auth, no personal data) and lands each event as a row. Adopted to the daemon architecture (../collectors-daemon-design.md, §11) as a warehouse-sink (Iceberg) daemon. Implementor: src/iceberg_daemons.rs (PolisenDaemon, parse_polisen), behind --features daemon. Rides the existing generic REST/JSON record mapper rest::parse_records driven by the RestCollector::polisen() preset's field map (records at the document root — the empty pointer).

Config trait (Settings ▸ Collectors ▸ polisen-events)

enabled: bool
url:     String   // events API   (default https://polisen.se/api/events; optionally ?locationname=&type=)
region:  String   // advisory — encode as ?locationname= in the URL
table:   String   // Iceberg table (default polisen_events)

State machine (State trait)

Offline → Downloading(fetch %) → Indexing(parse JSON) → Online     // event rows landed
        → Failed{reason}                                           // empty-is-RED / fetch/parse error

The State Facet renders sink=iceberg, phase, table, rows_written, last_run_unix, error. Green in the infra matrix only when ≥1 event row is landed.

Storage — Iceberg (warehouse-sink)

Rows land through CollectorCtx.warehouse (WarehouseSink) into polisen_events (columns: id, datetime, name, type, summary, url, location_name, gps). No S3 bucket.

Acquisition — the fetch seam (GET)

The events array is fetched through CollectorCtx.fetch GET (korp = the shared rustls HTTP core; tests = a canned Fetcher::from_map fixture, no live gov API). Fetch + parse run off the async reactor via spawn_blocking.

empty-is-RED

An enabled collector that parses to 0 events is a loud Failed{reason:"…(empty-is-RED)"} (red in the matrix), never a silent green.

Tests (`src/iceberg_daemons.rs` + `tests/collector_daemons_register.rs`)

polisen_daemon_reaches_online_and_sinks_events — the synthetic Polisen array (2 incidents) drives fetch→parse→append→Online, 2 rows in polisen_events, facet table=polisen_events.
batch6_empty_sources_are_red_not_silently_green — an empty [] array ⇒ Failed/red.
batch6_daemons_go_red_then_green_in_the_register — absent → RED (never-run) → GREEN (Online) as read back out-of-process through a RegisterReader.

Credential note

Open API, no key — fully exercised live and offline. (Measured standalone: serve reached ONLINE and landed 500 rows to polisen_events with no korp server, its phase readable via korp-collectors status from a separate process.)

Collector: polisen-events (adopted — WAVE 2, batch 6)