feat(python): implement Mapping protocol for IFD and GeoKeyDirectory

python/python/async_tiff/_geo.pyi

@@ -1,4 +1,15 @@
+from collections.abc import Iterable
+from typing import Any
+
 class GeoKeyDirectory:
+    def keys(self) -> list[str]:
+        """A list of string keys representing the GeoKey fields."""
+    def __eq__(self, value: object) -> bool: ...
+    def __iter__(self) -> Iterable[str]:
+        """An iterable of string keys representing the GeoKey fields."""
+    def __getitem__(self, key: str) -> Any:
+        """Access GeoKey fields by string key."""
+
     @property
     def model_type(self) -> int | None: ...
     @property

python/python/async_tiff/_ifd.pyi

@@ -1,3 +1,5 @@
+from collections.abc import Iterable
+from typing import Any
 from .enums import (
     CompressionMethod,
     PhotometricInterpretation,
@@ -11,6 +13,14 @@ from ._geo import GeoKeyDirectory
 Value = int | float | str | tuple[int, int] | list[Value]
 
 class ImageFileDirectory:
+    def keys(self) -> list[str]:
+        """A list of string keys representing the IFD fields."""
+    def __eq__(self, value: object) -> bool: ...
+    def __iter__(self) -> Iterable[str]:
+        """An iterable of string keys representing the IFD fields."""
+    def __getitem__(self, key: str) -> Any:
+        """Access IFD fields by string key."""
+
     @property
     def new_subfile_type(self) -> int | None: ...
     @property

python/src/geo.rs

@@ -1,7 +1,9 @@
 use async_tiff::geo::GeoKeyDirectory;
 use pyo3::prelude::*;
+use pyo3::IntoPyObjectExt;
 
-#[pyclass(name = "GeoKeyDirectory")]
+#[pyclass(name = "GeoKeyDirectory", frozen, eq)]
+#[derive(PartialEq)]
 pub(crate) struct PyGeoKeyDirectory {
     #[pyo3(get)]
     model_type: Option<u16>,
@@ -97,6 +99,214 @@ pub(crate) struct PyGeoKeyDirectory {
     vertical_units: Option<u16>,
 }
 
+#[pymethods]
+impl PyGeoKeyDirectory {
+    /// This exists to implement the Mapping protocol, so we support `dict(gkd)`.`
+    fn keys(&self) -> Vec<&'static str> {
+        let mut keys = vec![];
+        if self.model_type.is_some() {
+            keys.push("model_type");
+        }
+        if self.raster_type.is_some() {
+            keys.push("raster_type");
+        }
+        if self.citation.is_some() {
+            keys.push("citation");
+        }
+        if self.geographic_type.is_some() {
+            keys.push("geographic_type");
+        }
+        if self.geog_citation.is_some() {
+            keys.push("geog_citation");
+        }
+        if self.geog_geodetic_datum.is_some() {
+            keys.push("geog_geodetic_datum");
+        }
+        if self.geog_prime_meridian.is_some() {
+            keys.push("geog_prime_meridian");
+        }
+        if self.geog_linear_units.is_some() {
+            keys.push("geog_linear_units");
+        }
+        if self.geog_linear_unit_size.is_some() {
+            keys.push("geog_linear_unit_size");
+        }
+        if self.geog_angular_units.is_some() {
+            keys.push("geog_angular_units");
+        }
+        if self.geog_angular_unit_size.is_some() {
+            keys.push("geog_angular_unit_size");
+        }
+        if self.geog_ellipsoid.is_some() {
+            keys.push("geog_ellipsoid");
+        }
+        if self.geog_semi_major_axis.is_some() {
+            keys.push("geog_semi_major_axis");
+        }
+        if self.geog_semi_minor_axis.is_some() {
+            keys.push("geog_semi_minor_axis");
+        }
+        if self.geog_inv_flattening.is_some() {
+            keys.push("geog_inv_flattening");
+        }
+        if self.geog_azimuth_units.is_some() {
+            keys.push("geog_azimuth_units");
+        }
+        if self.geog_prime_meridian_long.is_some() {
+            keys.push("geog_prime_meridian_long");
+        }
+        if self.projected_type.is_some() {
+            keys.push("projected_type");
+        }
+        if self.proj_citation.is_some() {
+            keys.push("proj_citation");
+        }
+        if self.projection.is_some() {
+            keys.push("projection");
+        }
+        if self.proj_coord_trans.is_some() {
+            keys.push("proj_coord_trans");
+        }
+        if self.proj_linear_units.is_some() {
+            keys.push("proj_linear_units");
+        }
+        if self.proj_linear_unit_size.is_some() {
+            keys.push("proj_linear_unit_size");
+        }
+        if self.proj_std_parallel1.is_some() {
+            keys.push("proj_std_parallel1");
+        }
+        if self.proj_std_parallel2.is_some() {
+            keys.push("proj_std_parallel2");
+        }
+        if self.proj_nat_origin_long.is_some() {
+            keys.push("proj_nat_origin_long");
+        }
+        if self.proj_nat_origin_lat.is_some() {
+            keys.push("proj_nat_origin_lat");
+        }
+        if self.proj_false_easting.is_some() {
+            keys.push("proj_false_easting");
+        }
+        if self.proj_false_northing.is_some() {
+            keys.push("proj_false_northing");
+        }
+        if self.proj_false_origin_long.is_some() {
+            keys.push("proj_false_origin_long");
+        }
+        if self.proj_false_origin_lat.is_some() {
+            keys.push("proj_false_origin_lat");
+        }
+        if self.proj_false_origin_easting.is_some() {
+            keys.push("proj_false_origin_easting");
+        }
+        if self.proj_false_origin_northing.is_some() {
+            keys.push("proj_false_origin_northing");
+        }
+        if self.proj_center_long.is_some() {
+            keys.push("proj_center_long");
+        }
+        if self.proj_center_lat.is_some() {
+            keys.push("proj_center_lat");
+        }
+        if self.proj_center_easting.is_some() {
+            keys.push("proj_center_easting");
+        }
+        if self.proj_center_northing.is_some() {
+            keys.push("proj_center_northing");
+        }
+        if self.proj_scale_at_nat_origin.is_some() {
+            keys.push("proj_scale_at_nat_origin");
+        }
+        if self.proj_scale_at_center.is_some() {
+            keys.push("proj_scale_at_center");
+        }
+        if self.proj_azimuth_angle.is_some() {
+            keys.push("proj_azimuth_angle");
+        }
+        if self.proj_straight_vert_pole_long.is_some() {
+            keys.push("proj_straight_vert_pole_long");
+        }
+        if self.vertical.is_some() {
+            keys.push("vertical");
+        }
+        if self.vertical_citation.is_some() {
+            keys.push("vertical_citation");
+        }
+        if self.vertical_datum.is_some() {
+            keys.push("vertical_datum");
+        }
+        if self.vertical_units.is_some() {
+            keys.push("vertical_units");
+        }
+
+        keys
+    }
+
+    /// This exists to implement the Mapping protocol, so we support `dict(gkd)`.`
+    fn __iter__<'py>(&'py self, py: Python<'py>) -> PyResult<Bound<'py, PyAny>> {
+        self.keys().into_pyobject(py)?.call_method0("__iter__")
+    }
+
+    /// Get a GeoKeyDirectory property by name
+    /// This exists to implement the Mapping protocol, so we support `dict(gkd)`.`
+    fn __getitem__<'py>(&self, py: Python<'py>, key: &str) -> PyResult<Bound<'py, PyAny>> {
+        match key {
+            "model_type" => self.model_type.into_bound_py_any(py),
+            "raster_type" => self.raster_type.into_bound_py_any(py),
+            "citation" => self.citation.as_ref().into_bound_py_any(py),
+            "geographic_type" => self.geographic_type.into_bound_py_any(py),
+            "geog_citation" => self.geog_citation.as_ref().into_bound_py_any(py),
+            "geog_geodetic_datum" => self.geog_geodetic_datum.into_bound_py_any(py),
+            "geog_prime_meridian" => self.geog_prime_meridian.into_bound_py_any(py),
+            "geog_linear_units" => self.geog_linear_units.into_bound_py_any(py),
+            "geog_linear_unit_size" => self.geog_linear_unit_size.into_bound_py_any(py),
+            "geog_angular_units" => self.geog_angular_units.into_bound_py_any(py),
+            "geog_angular_unit_size" => self.geog_angular_unit_size.into_bound_py_any(py),
+            "geog_ellipsoid" => self.geog_ellipsoid.into_bound_py_any(py),
+            "geog_semi_major_axis" => self.geog_semi_major_axis.into_bound_py_any(py),
+            "geog_semi_minor_axis" => self.geog_semi_minor_axis.into_bound_py_any(py),
+            "geog_inv_flattening" => self.geog_inv_flattening.into_bound_py_any(py),
+            "geog_azimuth_units" => self.geog_azimuth_units.into_bound_py_any(py),
+            "geog_prime_meridian_long" => self.geog_prime_meridian_long.into_bound_py_any(py),
+            "projected_type" => self.projected_type.into_bound_py_any(py),
+            "proj_citation" => self.proj_citation.as_ref().into_bound_py_any(py),
+            "projection" => self.projection.into_bound_py_any(py),
+            "proj_coord_trans" => self.proj_coord_trans.into_bound_py_any(py),
+            "proj_linear_units" => self.proj_linear_units.into_bound_py_any(py),
+            "proj_linear_unit_size" => self.proj_linear_unit_size.into_bound_py_any(py),
+            "proj_std_parallel1" => self.proj_std_parallel1.into_bound_py_any(py),
+            "proj_std_parallel2" => self.proj_std_parallel2.into_bound_py_any(py),
+            "proj_nat_origin_long" => self.proj_nat_origin_long.into_bound_py_any(py),
+            "proj_nat_origin_lat" => self.proj_nat_origin_lat.into_bound_py_any(py),
+            "proj_false_easting" => self.proj_false_easting.into_bound_py_any(py),
+            "proj_false_northing" => self.proj_false_northing.into_bound_py_any(py),
+            "proj_false_origin_long" => self.proj_false_origin_long.into_bound_py_any(py),
+            "proj_false_origin_lat" => self.proj_false_origin_lat.into_bound_py_any(py),
+            "proj_false_origin_easting" => self.proj_false_origin_easting.into_bound_py_any(py),
+            "proj_false_origin_northing" => self.proj_false_origin_northing.into_bound_py_any(py),
+            "proj_center_long" => self.proj_center_long.into_bound_py_any(py),
+            "proj_center_lat" => self.proj_center_lat.into_bound_py_any(py),
+            "proj_center_easting" => self.proj_center_easting.into_bound_py_any(py),
+            "proj_center_northing" => self.proj_center_northing.into_bound_py_any(py),
+            "proj_scale_at_nat_origin" => self.proj_scale_at_nat_origin.into_bound_py_any(py),
+            "proj_scale_at_center" => self.proj_scale_at_center.into_bound_py_any(py),
+            "proj_azimuth_angle" => self.proj_azimuth_angle.into_bound_py_any(py),
+            "proj_straight_vert_pole_long" => {
+                self.proj_straight_vert_pole_long.into_bound_py_any(py)
+            }
+            "vertical" => self.vertical.into_bound_py_any(py),
+            "vertical_citation" => self.vertical_citation.as_ref().into_bound_py_any(py),
+            "vertical_datum" => self.vertical_datum.into_bound_py_any(py),
+            "vertical_units" => self.vertical_units.into_bound_py_any(py),
+            _ => Err(pyo3::exceptions::PyKeyError::new_err(format!(
+                "Unknown IFD property: {}",
+                key
+            ))),
+        }
+    }
+}
+
 impl From<PyGeoKeyDirectory> for GeoKeyDirectory {
     fn from(value: PyGeoKeyDirectory) -> Self {
         Self {