Initial GeoIntel V1 foundation

backend/app/services/raster_service.py

@@ -0,0 +1,51 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+from app.core.errors import AppError
+
+
+def _import_rasterio():
+    import importlib
+
+    rasterio = importlib.import_module("rasterio")
+    errors = importlib.import_module("rasterio.errors")
+    return rasterio, errors
+
+
+def extract_raster_metadata(path: str) -> dict:
+    try:
+        rasterio, errors = _import_rasterio()
+    except Exception as exc:  # pragma: no cover - exercised via API-level fallback tests
+        raise AppError(
+            code="RASTER_PROCESSING_UNAVAILABLE",
+            message="Raster processing unavailable. Install rasterio and GDAL-compatible drivers to enable raster metadata extraction.",
+            status_code=503,
+        ) from exc
+
+    dataset_path = Path(path)
+    try:
+        with rasterio.open(dataset_path) as dataset:
+            nodata = dataset.nodata
+            if isinstance(nodata, (list, tuple)):
+                nodata_value = [None if value is None else float(value) for value in nodata]
+            else:
+                nodata_value = None if nodata is None else float(nodata)
+
+            transform = dataset.transform.to_gdal() if hasattr(dataset, "transform") else None
+            return {
+                "driver": dataset.driver,
+                "width": int(dataset.width),
+                "height": int(dataset.height),
+                "band_count": int(dataset.count),
+                "crs": str(dataset.crs) if dataset.crs else None,
+                "bounds": list(dataset.bounds),
+                "resolution": list(dataset.res),
+                "dtype": list(dataset.dtypes),
+                "nodata": nodata_value,
+                "transform": list(transform) if transform is not None else None,
+            }
+    except Exception as exc:
+        if isinstance(exc, errors.RasterioIOError):
+            raise AppError(code="INVALID_RASTER", message="Uploaded raster file is invalid", status_code=400) from exc
+        raise AppError(code="RASTER_METADATA_ERROR", message="Unable to read raster metadata", status_code=400) from exc