Add column property accessors for selectors and descriptors (rerun-io…

…#7752)

### What
- Resolves: rerun-io#7747

### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested the web demo (if applicable):
* Using examples from latest `main` build:
[rerun.io/viewer](https://rerun.io/viewer/pr/7752?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
* Using full set of examples from `nightly` build:
[rerun.io/viewer](https://rerun.io/viewer/pr/7752?manifest_url=https://app.rerun.io/version/nightly/examples_manifest.json)
* [x] The PR title and labels are set such as to maximize their
usefulness for the next release's CHANGELOG
* [x] If applicable, add a new check to the [release
checklist](https://github.com/rerun-io/rerun/blob/main/tests/python/release_checklist)!
* [x] If have noted any breaking changes to the log API in
`CHANGELOG.md` and the migration guide

- [PR Build Summary](https://build.rerun.io/pr/7752)
- [Recent benchmark results](https://build.rerun.io/graphs/crates.html)
- [Wasm size tracking](https://build.rerun.io/graphs/sizes.html)

To run all checks from `main`, comment on the PR with `@rerun-bot
full-check`.

rerun_py/rerun_bindings/rerun_bindings.pyi

@@ -8,18 +8,68 @@ from .types import AnyColumn, ComponentLike, IndexValuesLike, ViewContentsLike
 class IndexColumnDescriptor:
     """A column containing the index values for when the component data was updated."""
 
+    def name(self) -> str:
+        """
+        The name of the index.
+
+        This property is read-only.
+        """
+        ...
+
 class IndexColumnSelector:
     """A selector for an index column."""
 
     def __init__(self, index: str): ...
+    def name(self) -> str:
+        """
+        The name of the index.
+
+        This property is read-only.
+        """
+        ...
 
 class ComponentColumnDescriptor:
     """A column containing the component data."""
 
+    @property
+    def entity_path(self) -> str:
+        """
+        The entity path.
+
+        This property is read-only.
+        """
+        ...
+
+    @property
+    def component_name(self) -> str:
+        """
+        The component name.
+
+        This property is read-only.
+        """
+        ...
+
 class ComponentColumnSelector:
     """A selector for a component column."""
 
     def __init__(self, entity_path: str, component: ComponentLike): ...
+    @property
+    def entity_path(self) -> str:
+        """
+        The entity path.
+
+        This property is read-only.
+        """
+        ...
+
+    @property
+    def component_name(self) -> str:
+        """
+        The component name.
+
+        This property is read-only.
+        """
+        ...
 
 class Schema:
     """The schema representing all columns in a [`Recording`][]."""

rerun_py/src/dataframe.rs

@@ -52,6 +52,11 @@ impl PyIndexColumnDescriptor {
     fn __repr__(&self) -> String {
         format!("Index(timeline:{})", self.0.timeline.name())
     }
+
+    #[getter]
+    fn name(&self) -> &str {
+        self.0.timeline.name()
+    }
 }
 
 impl From<TimeColumnDescriptor> for PyIndexColumnDescriptor {
@@ -78,6 +83,11 @@ impl PyIndexColumnSelector {
     fn __repr__(&self) -> String {
         format!("Index(timeline:{})", self.0.timeline)
     }
+
+    #[getter]
+    fn name(&self) -> &str {
+        &self.0.timeline
+    }
 }
 
 /// Python binding for [`ComponentColumnDescriptor`]
@@ -105,6 +115,16 @@ impl PyComponentColumnDescriptor {
     fn __eq__(&self, other: &Self) -> bool {
         self.0 == other.0
     }
+
+    #[getter]
+    fn entity_path(&self) -> String {
+        self.0.entity_path.to_string()
+    }
+
+    #[getter]
+    fn component_name(&self) -> &str {
+        &self.0.component_name
+    }
 }
 
 impl From<PyComponentColumnDescriptor> for ComponentColumnDescriptor {
@@ -135,6 +155,16 @@ impl PyComponentColumnSelector {
             self.0.entity_path, self.0.component_name
         )
     }
+
+    #[getter]
+    fn entity_path(&self) -> String {
+        self.0.entity_path.to_string()
+    }
+
+    #[getter]
+    fn component_name(&self) -> &str {
+        &self.0.component_name
+    }
 }
 
 /// Python binding for [`AnyColumn`] type-alias.

rerun_py/tests/unit/test_dataframe.py

@@ -95,6 +95,23 @@ def test_recording_info(self) -> None:
         assert self.recording.application_id() == APP_ID
         assert self.recording.recording_id() == str(RECORDING_ID)
 
+    def test_schema(self) -> None:
+        schema = self.recording.schema()
+
+        assert len(schema.index_columns()) == 3
+        # Points3DIndicator, Position3D, Color
+        assert len(schema.component_columns()) == 3
+
+        assert schema.index_columns()[0].name == "log_tick"
+        assert schema.index_columns()[1].name == "log_time"
+        assert schema.index_columns()[2].name == "my_index"
+        assert schema.component_columns()[0].entity_path == "/points"
+        assert schema.component_columns()[0].component_name == "rerun.components.Color"
+        assert schema.component_columns()[1].entity_path == "/points"
+        assert schema.component_columns()[1].component_name == "rerun.components.Points3DIndicator"
+        assert schema.component_columns()[2].entity_path == "/points"
+        assert schema.component_columns()[2].component_name == "rerun.components.Position3D"
+
     def test_full_view(self) -> None:
         view = self.recording.view(index="my_index", contents="points")
 

scripts/ci/python_check_signatures.py

@@ -112,6 +112,11 @@ def load_runtime_signatures(module_name: str) -> TotalSignature:
                     class_def[method_name] = inspect.signature(method_obj)
                 except Exception:
                     pass
+            # Get property getters
+            for method_name, method_obj in inspect.getmembers(
+                obj, lambda o: o.__class__.__name__ == "getset_descriptor"
+            ):
+                class_def[method_name] = Signature(parameters=[Parameter("self", Parameter.POSITIONAL_ONLY)])
             signatures[name] = class_def
 
     return signatures