Support openeo.api.process.Parameter as resolution in DataCube.resample_spatial() #897

Author: VincentVerelst

CHANGELOG.md

@@ -20,7 +20,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Removed
 
 ### Fixed
-
+- `DataCube.resample_spatial()` now supports `openeo.api.process.Parameter` objects for the `resolution` parameter.  ([#897](https://github.com/Open-EO/openeo-python-client/issues/897))
 
 ## [0.49.0] - 2026-04-01
 

openeo/metadata.py

@@ -19,6 +19,7 @@
 import pystac.extensions.eo
 import pystac.extensions.item_assets
 
+from openeo.api.process import Parameter
 from openeo.internal.jupyter import render_component
 from openeo.util import Rfc3339, deep_get
 from openeo.utils.normalize import normalize_resample_resolution, unique
@@ -494,10 +495,13 @@ def drop_dimension(self, name: str = None) -> CubeMetadata:
 
     def resample_spatial(
         self,
-        resolution: Union[float, Tuple[float, float], List[float]] = 0.0,
+        resolution: Union[float, Tuple[float, float], List[float], "Parameter"] = 0.0,
         projection: Union[int, str, None] = None,
     ) -> CubeMetadata:
-        resolution = normalize_resample_resolution(resolution)
+        if isinstance(resolution, Parameter):
+            normalized_resolution = None
+        else:
+            normalized_resolution = normalize_resample_resolution(resolution)
         if self._dimensions is None:
             # Best-effort fallback to work with
             dimensions = [
@@ -512,15 +516,25 @@ def resample_spatial(
         spatial_indices = [i for i, d in enumerate(dimensions) if isinstance(d, SpatialDimension)]
         if len(spatial_indices) != 2:
             raise MetadataException(f"Expected two spatial dimensions but found {spatial_indices=}")
-        assert len(resolution) == 2
-        for i, r in zip(spatial_indices, resolution):
-            dim: SpatialDimension = dimensions[i]
-            dimensions[i] = SpatialDimension(
-                name=dim.name,
-                extent=dim.extent,
-                crs=projection or dim.crs,
-                step=r if r != 0.0 else dim.step,
-            )
+        if normalized_resolution is not None:
+            assert len(normalized_resolution) == 2
+            for i, r in zip(spatial_indices, normalized_resolution):
+                dim: SpatialDimension = dimensions[i]
+                dimensions[i] = SpatialDimension(
+                    name=dim.name,
+                    extent=dim.extent,
+                    crs=projection or dim.crs,
+                    step=r if r != 0.0 else dim.step,
+                )
+        elif projection:
+            for i in spatial_indices:
+                dim: SpatialDimension = dimensions[i]
+                dimensions[i] = SpatialDimension(
+                    name=dim.name,
+                    extent=dim.extent,
+                    crs=projection,
+                    step=dim.step,
+                )
 
         return self._clone_and_update(dimensions=dimensions)
 

openeo/rest/datacube.py

@@ -809,7 +809,7 @@ def band(self, band: Union[str, int]) -> DataCube:
     @openeo_process
     def resample_spatial(
         self,
-        resolution: Union[float, Tuple[float, float], List[float]] = 0.0,
+        resolution: Union[float, Tuple[float, float], List[float], Parameter] = 0.0,
         projection: Union[int, str, None] = None,
         method: str = "near",
         align: str = "upper-left",

tests/rest/datacube/test_datacube.py

@@ -873,6 +873,46 @@ def test_resample_spatial_no_metadata(s2cube_without_metadata):
     ]
 
 
+def test_resample_spatial_parameter_resolution(s2cube):
+    """A Parameter object passed as resolution must not crash and must appear in the process graph."""
+    param = Parameter.number("res", description="The spatial resolution.")
+    cube = s2cube.resample_spatial(resolution=param, projection=32631)
+    assert get_download_graph(cube, drop_load_collection=True, drop_save_result=True) == {
+        "resamplespatial1": {
+            "process_id": "resample_spatial",
+            "arguments": {
+                "data": {"from_node": "loadcollection1"},
+                "resolution": {"from_parameter": "res"},
+                "projection": 32631,
+                "method": "near",
+                "align": "upper-left",
+            },
+        }
+    }
+    assert cube.metadata.spatial_dimensions == [
+        SpatialDimension(name="x", extent=None, crs=32631, step=None),
+        SpatialDimension(name="y", extent=None, crs=32631, step=None),
+    ]
+
+
+def test_resample_spatial_parameter_resolution_no_projection(s2cube):
+    """A Parameter resolution with no concrete projection leaves step and crs unchanged."""
+    param = Parameter.number("res", description="The spatial resolution.")
+    cube = s2cube.resample_spatial(resolution=param)
+    assert get_download_graph(cube, drop_load_collection=True, drop_save_result=True) == {
+        "resamplespatial1": {
+            "process_id": "resample_spatial",
+            "arguments": {
+                "data": {"from_node": "loadcollection1"},
+                "resolution": {"from_parameter": "res"},
+                "projection": None,
+                "method": "near",
+                "align": "upper-left",
+            },
+        }
+    }
+
+
 def test_resample_cube_spatial(s2cube):
     cube1 = s2cube.resample_spatial(resolution=[2.0, 3.0], projection=4578)
     cube2 = s2cube.resample_spatial(resolution=10, projection=32631)

tests/test_metadata.py

@@ -8,6 +8,7 @@
 import pystac
 import pytest
 
+from openeo.api.process import Parameter
 from openeo.metadata import (
     _PYSTAC_1_9_EXTENSION_INTERFACE,
     Band,
@@ -1279,6 +1280,35 @@ def test_metadata_resample_spatial(cube_metadata, kwargs, expected_x, expected_y
     assert metadata.band_dimension == cube_metadata.band_dimension
 
 
+@pytest.mark.parametrize("cube_metadata", [CUBE_METADATA_XYTB, CUBE_METADATA_TBXY])
+def test_metadata_resample_spatial_parameter_resolution_only(cube_metadata):
+    """When resolution is a Parameter, step should remain unchanged and crs should stay as-is."""
+    param = Parameter.number("res", description="The spatial resolution.")
+    metadata = cube_metadata.resample_spatial(resolution=param)
+    assert isinstance(metadata, CubeMetadata)
+    # step must not change because the resolution is unknown at build time
+    assert metadata.spatial_dimensions == [
+        SpatialDimension(name="x", extent=[2, 7], crs=4326, step=0.1),
+        SpatialDimension(name="y", extent=[49, 52], crs=4326, step=0.1),
+    ]
+    assert metadata.temporal_dimension == cube_metadata.temporal_dimension
+    assert metadata.band_dimension == cube_metadata.band_dimension
+
+
+@pytest.mark.parametrize("cube_metadata", [CUBE_METADATA_XYTB, CUBE_METADATA_TBXY])
+def test_metadata_resample_spatial_parameter_resolution_with_projection(cube_metadata):
+    """When resolution is a Parameter but projection is concrete, crs should be updated."""
+    param = Parameter.number("res", description="The spatial resolution.")
+    metadata = cube_metadata.resample_spatial(resolution=param, projection=32631)
+    assert isinstance(metadata, CubeMetadata)
+    assert metadata.spatial_dimensions == [
+        SpatialDimension(name="x", extent=[2, 7], crs=32631, step=0.1),
+        SpatialDimension(name="y", extent=[49, 52], crs=32631, step=0.1),
+    ]
+    assert metadata.temporal_dimension == cube_metadata.temporal_dimension
+    assert metadata.band_dimension == cube_metadata.band_dimension
+
+
 @pytest.mark.parametrize("cube_metadata", [CUBE_METADATA_XYTB, CUBE_METADATA_TBXY])
 def test_metadata_resample_cube_spatial(cube_metadata):
     metadata1 = cube_metadata.resample_spatial(resolution=(11, 22), projection=32631)