Metadata Improvements (#106)

* add crs to GetMetadata requests

* check for coord in variables for additional_coords

* use default values in GetMap for additional coords not specified in request params

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

xpublish_wms/query.py

@@ -44,6 +44,10 @@ class WMSGetMetadataQuery(WMSBaseQuery):
             description="Bounding box to use for calculating min and max in the format 'minx,miny,maxx,maxy'",
         ),
     )
+    crs: Literal["EPSG:4326", "EPSG:3857"] = Field(
+        "EPSG:4326",
+        description="Coordinate reference system to use for the query. EPSG:4326 and EPSG:3857 are supported for this request",
+    )
     time: Optional[str] = (
         Field(
             None,
@@ -273,6 +277,7 @@ def wms_query(
             day=day,
             range=range,
             bbox=bbox,
+            crs=crs if srs is None else srs,
             time=time,
             elevation=elevation,
         )

xpublish_wms/wms/get_map.py

@@ -174,7 +174,10 @@ def ensure_query_types(
         self.autoscale = query.autoscale
 
         available_selectors = ds.gridded.additional_coords(ds[self.parameter])
-        self.dim_selectors = {k: query_params[k] for k in available_selectors}
+        self.dim_selectors = {
+            k: query_params[k] if k in query_params else None
+            for k in available_selectors
+        }
 
     def select_layer(self, ds: xr.Dataset) -> xr.DataArray:
         """
@@ -235,23 +238,34 @@ def select_elevation(self, ds: xr.Dataset, da: xr.DataArray) -> xr.DataArray:
     def select_custom_dim(self, da: xr.DataArray) -> xr.DataArray:
         """
         Select other dimension, ensuring a 2D array
+
+        If dimension is provided :
+            - use xarray to access custom coord
+            - method nearest to ensure at least one result
+
+        Otherwise:
+            - Get first value of coord
+
         :param da:
         :return:
         """
         # Filter dimension from custom query, if any
         for dim, value in self.dim_selectors.items():
             if dim in da.coords:
-                dtype = da[dim].dtype
-                method = None
-                if "timedelta" in str(dtype):
-                    value = pd.to_timedelta(value)
-                elif np.issubdtype(dtype, np.integer):
-                    value = int(value)
-                    method = "nearest"
-                elif np.issubdtype(dtype, np.floating):
-                    value = float(value)
-                    method = "nearest"
-                da = da.sel({dim: value}, method=method)
+                if value is None:
+                    da = da.isel({dim: 0})
+                else:
+                    dtype = da[dim].dtype
+                    method = None
+                    if "timedelta" in str(dtype):
+                        value = pd.to_timedelta(value)
+                    elif np.issubdtype(dtype, np.integer):
+                        value = int(value)
+                        method = "nearest"
+                    elif np.issubdtype(dtype, np.floating):
+                        value = float(value)
+                        method = "nearest"
+                    da = da.sel({dim: value}, method=method)
 
         # Squeeze single value dimensions
         da = da.squeeze()

xpublish_wms/wms/get_metadata.py

@@ -105,7 +105,7 @@ def get_minmax(
         bbox=query.bbox if not entire_layer else "-180,-90,180,90",
         width=1 if entire_layer else 512,
         height=1 if entire_layer else 512,
-        crs="EPSG:4326",
+        crs=query.crs,
         time=query.time,
         elevation=query.elevation,
         styles="raster/default",
@@ -139,7 +139,10 @@ def get_layer_details(ds: xr.Dataset, layer_name: str) -> dict:
 
     additional_coords = ds.gridded.additional_coords(da)
     additional_coord_values = {
-        coord: da.cf.coords[coord].values.tolist() for coord in additional_coords
+        coord: (
+            da.cf.coords[coord] if coord in da.cf.coords else da[coord]
+        ).values.tolist()
+        for coord in additional_coords
     }
 
     return {