Converter for Baden-Württemberg, Germany

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Introduce FiboaBaseConverter.use_variant_as_determination for setting proper determination_date
 - Update years for DK (2025, 2026)
 - Update fr-converter to support 2021/2022 files
+- Converter for Baden-Württemberg, Germany (GISELa LPIS reference parcels, 2018-2022)
 - Converter for Lithuania KŽS reference parcels (lt_kzs), reading the geoportal.lt ArcGIS REST service
 - Support Esri JSON and server-side filters in EsriRESTConverterMixin (rest_format, rest_params["where"])
 - Converter for Bavaria, Germany LPIS field blocks (de_by_block)

fiboa_cli/datasets/de_bw.py

@@ -0,0 +1,96 @@
+import re
+from urllib.parse import urlencode
+
+import pandas as pd
+import requests
+from vecorel_cli.conversion.admin import AdminConverterMixin
+
+from ..conversion.fiboa_converter import FiboaBaseConverter
+from .commons.de_iacs import DEIACSMixin
+
+BASE_URL = "https://owsproxy.lgl-bw.de/owsproxy/wfs/WFS_LW-BW_GISELA_landw_Parzellen"
+FARMLAND = "Bodenbedeckung IN ('Ackerland','Grünland','Dauerkultur')"
+
+# GISELa publishes the German label only, without the code. These are the values of the national
+# de.iacs codelist that the labels correspond to. Ackerland and Dauerkultur are exact; the codelist
+# defines GL as *permanent* grassland, which BW's documentation does not confirm either way.
+AREA_TYPES = {"Ackerland": "AL", "Grünland": "GL", "Dauerkultur": "DK"}
+
+
+class DEBWConverter(AdminConverterMixin, DEIACSMixin, FiboaBaseConverter):
+    id = "de_bw"
+    admin_subdivision_code = "BW"
+    short_name = "Germany, Baden-Württemberg"
+    title = "Field boundaries for Baden-Württemberg, Germany"
+    description = """
+GISELa is the Land Parcel Identification System (LPIS) of Baden-Württemberg, the reference system for
+area-based agricultural payments. Unlike most German states, which use field blocks ("Feldblöcke"),
+Baden-Württemberg uses the cadastral parcel ("Katasterflurstück") as its reference parcel, subdivided
+by land cover ("Bodenbedeckung") - so the same FLIK can appear on several rows. This converter keeps
+the agricultural classes (arable land, grassland, permanent crops) and drops landscape elements and
+non-agricultural areas. The area given is the maximum area eligible for direct payments, not the
+geometric area of the polygon.
+"""
+
+    provider = "Ministerium für Ländlichen Raum und Verbraucherschutz Baden-Württemberg <https://mlr.baden-wuerttemberg.de>"
+    attribution = "© MLR Baden-Württemberg, dl-de/by-2-0"
+    license = "DL-DE-BY-2.0"
+
+    extensions = {"https://fiboa.org/flik-extension/v0.2.0/schema.yaml"}
+
+    # One variant per published year, newest first -> 2022 is the default.
+    variants = {str(year): str(year) for year in range(2022, 2017, -1)}
+
+    page_size = 50_000
+
+    # read_geojson calls open() without an encoding, so it follows the platform locale:
+    # UTF-8 on Linux/macOS, cp1252 on Windows, which would turn "Grünland" into mojibake.
+    open_options = dict(encoding="utf-8")
+
+    columns = {
+        "geometry": "geometry",
+        "Geo-ID": "id",
+        "FLIK": "flik",  # NOT the id: several rows share one FLIK
+        "area_type": "crop:code",  # derived from Bodenbedeckung in migrate()
+        "FlaecheInHa": "metrics:area",
+        "Antragsjahr": "determination:datetime",
+    }
+    column_migrations = {"Antragsjahr": lambda col: pd.to_datetime(col, format="%Y")}
+
+    def get_urls(self):
+        latest = next(iter(self.variants))
+        if not self.variant:
+            self.variant = latest
+
+        params = {
+            "service": "WFS",
+            "version": "2.0.0",
+            "request": "GetFeature",
+            "typeNames": f"lw:v_gisela_landw_parzellen_{self.variant}",
+            "outputFormat": "application/json",
+            "cql_filter": FARMLAND,
+            # NO srsName: the server rounds to 4 decimals in the output CRS, so asking
+            # for degrees would quantise coordinates to ~10 m. Fetch native, relabel below.
+        }
+
+        # One cheap request so the page list is derived from the server, not hardcoded.
+        hits = requests.get(BASE_URL, params={**params, "resultType": "hits"})
+        hits.raise_for_status()
+        total = int(re.search(r'numberMatched="(\d+)"', hits.text).group(1))
+
+        query = urlencode({**params, "count": self.page_size})
+        return {
+            f"{BASE_URL}?{query}&startIndex={start}": f"de_bw_{self.variant}_{start}.json"
+            for start in range(0, total, self.page_size)
+        }
+
+    def file_migration(self, gdf, path, uri, layer=None):
+        # read_geojson hardcodes crs="EPSG:4326"; the payload is really EPSG:25832.
+        # allow_override is required because a CRS is already set.
+        return gdf.set_crs("EPSG:25832", allow_override=True)
+
+    def migrate(self, gdf):
+        gdf["area_type"] = gdf["Bodenbedeckung"].map(AREA_TYPES)
+        # read_geojson injects its own "id" column from the GML feature id.
+        # Drop it so renaming Geo-ID -> id does not create two columns called "id".
+        return super().migrate(gdf.drop(columns=["id"]))

fiboa_cli/datasets/de_he.py

@@ -40,6 +40,7 @@ class DEHEConverter(AdminConverterMixin, DEIACSMixin, FiboaBaseConverter):
         "declaredArea": "metrics:area",  # in hectares, hence the area_is_in_ha default
         "validFrom": "determination:datetime",
     }
+    open_options = dict(encoding="utf-8")
     column_migrations = {
         "validFrom": lambda col: pd.to_datetime(col, format="%d.%m.%Y"),
     }