Merge pull request #471 from ungarj/handle_empty_vector_file

enable handling empty vector files as input

mapchete/commands/_convert.py

@@ -421,7 +421,7 @@ def _input_fiona_info(inp):
             crs=src.crs,
             zoom_levels=None,
             input_type="vector",
-            bounds=src.bounds,
+            bounds=src.bounds if len(src) else None,
         )
 
 

mapchete/formats/default/vector_file.py

@@ -7,7 +7,7 @@
 from cached_property import cached_property
 import fiona
 import logging
-from shapely.geometry import box
+from shapely.geometry import box, Point
 from rasterio.crs import CRS
 
 from mapchete.formats import base
@@ -173,8 +173,11 @@ def bbox(self, out_crs=None):
         out_crs = self.pyramid.crs if out_crs is None else out_crs
         if self._bbox_cache is None:
             with fiona.open(self.path) as inp:
-                self._bbox_cache = CRS(inp.crs), tuple(inp.bounds)
+                self._bbox_cache = CRS(inp.crs), tuple(inp.bounds) if len(inp) else None
         inp_crs, bounds = self._bbox_cache
+        if bounds is None:
+            # this creates an empty GeometryCollection object
+            return Point()
         # TODO find a way to get a good segmentize value in bbox source CRS
         return reproject_geometry(
             box(*bounds), src_crs=inp_crs, dst_crs=out_crs, clip_to_crs_bounds=False

test/conftest.py

@@ -121,6 +121,12 @@ def s2_band_remote():
     return "s3://mapchete-test/4band_test.tif"
 
 
+@pytest.fixture
+def empty_gpkg():
+    """Fixture for HTTP raster."""
+    return os.path.join(TESTDATA_DIR, "empty.gpkg")
+
+
 @pytest.fixture
 def s3_metadata_json():
     """

test/test_commands.py

@@ -738,3 +738,13 @@ def test_index_text(cleantopo_br):
 def test_index_errors(mp_tmpdir, cleantopo_br):
     with pytest.raises(ValueError):
         index(cleantopo_br.dict, zoom=5)
+
+
+def test_convert_empty_gpkg(empty_gpkg, mp_tmpdir):
+    convert(
+        empty_gpkg,
+        mp_tmpdir,
+        output_pyramid="geodetic",
+        zoom=5,
+        output_format="GeoJSON",
+    )