`geo://`¶

Pure-Go geospatial processor (backed by pkg/geo, no cgo). The producer treats the exchange body as a geometry and runs one operation against it: parse, centroid, bounding box, area, length, geohash, distance, point-in-polygon, and radius containment. It is the route-level counterpart of the sl::gis Starlang module and the geo.* agent tools — all three share pkg/geo.

URI shape¶

geo://<operation>?precision=7&to=lon,lat&point=lon,lat&meters=5000

Producer-only — CreateConsumer returns an error.

Token	Description
`<operation>`	Required — one of `parse`, `centroid`, `bbox`, `area`, `length`, `geohash`, `distance`, `contains`, `dwithin`.

Coordinates are always (longitude, latitude) in WGS84 (EPSG:4326), matching GeoJSON axis order.

Parameters¶

Param	Type	Default	Producer/Consumer/Both	Description
`precision`	integer	`7`	Producer	`geohash` — number of characters (1–12).
`to`	string	—	Producer	`distance` — the reference point as `"lon,lat"`.
`point`	string	—	Producer	`contains` / `dwithin` — the test point as `"lon,lat"`.
`meters`	number	—	Producer	`dwithin` — the radius in meters.

Body contracts¶

The body is interpreted as a geometry in any of these forms:

Body type	Interpreted as
GeoJSON object (`map[string]any`)	a geometry via GeoJSON
string / `[]byte` starting `{` or `[`	GeoJSON
string / `[]byte` otherwise	WKT (e.g. `POINT(30 10)`, `POLYGON((...))`)
`[]float64` / `[]any` of length ≥ 2	a `[lon, lat]` Point

Operations¶

Operation	Body	Output	Content-Type
`parse`	any geometry	normalized GeoJSON object	`application/geo+json`
`centroid`	any geometry	centroid Point (GeoJSON object)	`application/geo+json`
`bbox`	any geometry	`[]float64` = `[minLon, minLat, maxLon, maxLat]`	—
`area`	any geometry	`float64` — area in m² (geodesic)	—
`length`	any geometry	`float64` — length/perimeter in meters (geodesic)	—
`geohash`	a Point	`string` — geohash at `precision`	—
`distance`	a Point + `to=lon,lat`	`float64` — geodesic meters between the two points	—
`contains`	a geometry + `point=lon,lat`	`bool` — is the point inside the geometry	—
`dwithin`	a Point + `point=lon,lat` + `meters`	`bool` — is the body point within `meters` of `point`	—

Distances/areas are geodesic (Haversine / spherical), consistent with pkg/geo and sl::gis.

Headers¶

Written by the producer¶

Header	Description
`geo.operation`	The operation executed.
`Content-Type`	Set to `application/geo+json` only for GeoJSON geometry output (`parse`, `centroid`).

Examples¶

Geohash a coordinate (body is a [lon, lat] pair):

- target: geo://geohash?precision=5
# body [-5.6, 42.6] -> "ezs42"

Centroid of a WKT polygon, emitted as GeoJSON:

- set-body:
    constant: "POLYGON((-1 -1, 1 -1, 1 1, -1 1, -1 -1))"
- target: geo://centroid
# body -> {"type":"Point","coordinates":[0,0]}, Content-Type application/geo+json

Point-in-polygon test used to branch a route:

- set-body:
    constant: "POLYGON((-74.02 40.70, -73.95 40.70, -73.95 40.75, -74.02 40.75, -74.02 40.70))"
- target: geo://contains?point=-73.98,40.72
# body -> true

Distance between two points (meters):

- target: geo://distance?to=-73.9857,40.7484
# body [-74.006, 40.7128] -> ~5000 (meters to the reference point)

Behavior notes¶

Pure Go — no GEOS/GDAL/PROJ; the operations above are the pure-Go tier. Heavy topology (buffer/union/arbitrary intersection) and binary formats (shapefile/GeoTIFF) are out of scope.
Axis order — (lon, lat). A common mistake is passing lat,lon; results will be far from expected.
Producer-only — use it as a target: step; the transformed body flows to the next step.

Source¶

pkg/component/geo/geo.go

geo://¶