added bootstrap

README.md

@@ -4,10 +4,11 @@ HTTP API for radio visibility, terrain profiles, Fresnel/LOS checks, link budget
 viewshed, and coverage calculations.
 
 This repository follows `SPEC.md`. The first implementation pass creates the full
-service skeleton and the pure RF/math kernels. Integrations that require real DEM,
-PostGIS data, pycraf, ITM/P.1812, or external viewshed binaries are exposed through
-stable interfaces and return explicit "not implemented" responses until the
-corresponding data pipeline is connected.
+service skeleton, pure RF/math kernels, and Copernicus DEM sampling. Integrations
+that require PostGIS data, pycraf, ITM/P.1812, landcover/canopy rasters, or
+external viewshed binaries are exposed through stable interfaces and return
+explicit "not implemented" responses until the corresponding data pipeline is
+connected.
 
 ## Layout
 
@@ -25,6 +26,18 @@ docker compose up --build api redis postgis
 
 The API is served at `http://localhost:8000`, with OpenAPI docs at `/docs`.
 
+## DEM Bootstrap
+
+Download Copernicus DEM GLO-30 COG tiles for Saint Petersburg and Leningrad Oblast:
+
+```bash
+python scripts/bootstrap_dem.py --bbox 27.3,58.4,35.8,61.4 --output-dir data/dem
+docker compose restart api worker
+```
+
+The API samples all `.tif`/`.tiff` files under `DEM_PATH` recursively. In Docker,
+the default `DEM_PATH=/data/dem` points to the mounted `./data/dem` directory.
+
 For local Python development:
 
 ```bash