Fix warning raster format mismatch ome-zarr

src/spatialdata/_io/format.py

@@ -91,7 +91,9 @@ def validate_coordinate_transformations(
             import json
 
             json0 = [json.dumps(t) for t in transformations]
-            from spatialdata.transformations.ngff.ngff_transformations import NgffBaseTransformation
+            from spatialdata.transformations.ngff.ngff_transformations import (
+                NgffBaseTransformation,
+            )
 
             parsed = [NgffBaseTransformation.from_dict(t) for t in transformations]
             json1 = [json.dumps(p.to_dict()) for p in parsed]
@@ -298,6 +300,10 @@ def spatialdata_format_version(self) -> str:
     "0.4-dev-spatialdata": FormatV04(),
     "0.5-dev-spatialdata": FormatV05(),
 }
+sdata_zarr_version_to_raster_format: dict[str, FormatV04 | FormatV05] = {
+    fmt.version: fmt  # type: ignore[attr-defined]
+    for fmt in [RasterFormatV01(), RasterFormatV02(), RasterFormatV03()]
+}
 RasterFormats: dict[str, RasterFormatType] = {
     "0.1": RasterFormatV01(),
     "0.2": RasterFormatV02(),

src/spatialdata/_io/io_zarr.py

@@ -35,7 +35,7 @@ def _read_zarr_group_spatialdata_element(
     read_func: Callable[..., Any],
     group_name: Literal["images", "labels", "shapes", "points", "tables"],
     element_type: Literal["image", "labels", "shapes", "points", "tables"],
-    element_container: dict[str, Raster_T] | dict[str, DaskDataFrame] | dict[str, GeoDataFrame] | dict[str, AnnData],
+    element_container: (dict[str, Raster_T] | dict[str, DaskDataFrame] | dict[str, GeoDataFrame] | dict[str, AnnData]),
     on_bad_files: Literal[BadFileHandleMethod.ERROR, BadFileHandleMethod.WARN],
 ) -> None:
     with handle_read_errors(
@@ -80,7 +80,11 @@ def _read_zarr_group_spatialdata_element(
             logger.debug(f"Found {count} elements in {group}")
 
 
-def get_raster_format_for_read(group: zarr.Group, sdata_version: Literal["0.1", "0.2"]) -> Format:
+def get_raster_format_for_read(
+    group: zarr.Group,
+    sdata_version: Literal["0.1", "0.2"],
+    return_ome_zarr_format: bool = False,
+) -> Format:
     """Get raster format of stored raster data.
 
     This checks the image or label element zarr group metadata to retrieve the format that is used by
@@ -92,18 +96,27 @@ def get_raster_format_for_read(group: zarr.Group, sdata_version: Literal["0.1",
         The zarr group of the raster element to be read.
     sdata_version
         The version of the SpatialData zarr store retrieved from the spatialdata attributes.
+    return_ome_zarr_format
+        Whether to return the ome-zarr Format or a SpatialData raster format class (which is a subclass of Format)
 
     Returns
     -------
     The ome-zarr format to use for reading the raster element.
     """
-    from spatialdata._io.format import sdata_zarr_version_to_ome_zarr_format
+    from spatialdata._io.format import (
+        sdata_zarr_version_to_ome_zarr_format,
+        sdata_zarr_version_to_raster_format,
+    )
 
     if sdata_version == "0.1":
         group_version = group.metadata.attributes["multiscales"][0]["version"]
-    if sdata_version == "0.2":
+    elif sdata_version == "0.2":
         group_version = group.metadata.attributes["ome"]["version"]
-    return sdata_zarr_version_to_ome_zarr_format[group_version]
+    else:
+        raise ValueError(f"Unknown SpatialData zarr version {sdata_version}")
+    if return_ome_zarr_format:
+        return sdata_zarr_version_to_ome_zarr_format[group_version]
+    return sdata_zarr_version_to_raster_format[group_version]
 
 
 def read_zarr(
@@ -146,7 +159,7 @@ def read_zarr(
     if sdata_version == "0.1":
         warnings.warn(
             "SpatialData is not stored in the most current format. If you want to use Zarr v3"
-            ", please write the store to a new location.",
+            ", please write the store to a new location using `sdata.write()`.",
             UserWarning,
             stacklevel=2,
         )
@@ -177,7 +190,11 @@ def read_zarr(
         "shapes": (_read_shapes, "shapes", shapes),
         "tables": (_read_table, "tables", tables),
     }
-    for group_name, (read_func, element_type, element_container) in group_readers.items():
+    for group_name, (
+        read_func,
+        element_type,
+        element_container,
+    ) in group_readers.items():
         _read_zarr_group_spatialdata_element(
             root_group=root_group,
             root_store_path=root_store_path,