feat(python): add namespace_client() method to connection classes

Add namespace_client() method that returns the equivalent namespace client
for different connection types:
- Native storage (LanceDBConnection): returns DirectoryNamespace
- Namespace connection: returns the backing namespace client
- Enterprise connection (RemoteDBConnection): returns RestNamespace

Implementation uses a hybrid approach:
- Rust side exposes namespace_client_config() returning (impl, properties)
- Python side uses lance_namespace.connect() to construct the namespace

Changes:
- Add namespace_client_config() to Database trait and implementations
- Add PyO3 binding for namespace_client_config()
- Add namespace_client() to DBConnection, LanceDBConnection, AsyncConnection
- Add namespace_client() to RemoteDBConnection
- Add namespace_client() to LanceNamespaceDBConnection and async variant
- Add tests for namespace_client() functionality
- Update pylance dependency to >=5.0.0b5

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

python/pyproject.toml

@@ -45,7 +45,7 @@ repository = "https://github.com/lancedb/lancedb"
 
 [project.optional-dependencies]
 pylance = [
-    "pylance>=5.0.0b3",
+    "pylance>=5.0.0b5",
 ]
 tests = [
     "aiohttp>=3.9.0",
@@ -59,7 +59,7 @@ tests = [
     "polars>=0.19, <=1.3.0",
     "tantivy>=0.20.0",
     "pyarrow-stubs>=16.0",
-    "pylance>=5.0.0b3",
+    "pylance>=5.0.0b5",
     "requests>=2.31.0",
     "datafusion>=52,<53",
 ]

python/python/lancedb/_lancedb.pyi

@@ -151,6 +151,9 @@ class Connection(object):
     async def drop_all_tables(
         self, namespace_path: Optional[List[str]] = None
     ) -> None: ...
+    async def namespace_client_config(
+        self,
+    ) -> Dict[str, Any]: ...
 
 class Table:
     def name(self) -> str: ...

python/python/lancedb/db.py

@@ -23,11 +23,13 @@ from lancedb.embeddings.registry import EmbeddingFunctionRegistry
 from lancedb.common import data_to_reader, sanitize_uri, validate_schema
 from lancedb.background_loop import LOOP
 from lance_namespace import (
+    LanceNamespace,
     ListNamespacesResponse,
     CreateNamespaceResponse,
     DropNamespaceResponse,
     DescribeNamespaceResponse,
     ListTablesResponse,
+    connect as namespace_connect,
 )
 
 from . import __version__
@@ -507,6 +509,26 @@ class DBConnection(EnforceOverrides):
     def uri(self) -> str:
         return self._uri
 
+    def namespace_client(self) -> LanceNamespace:
+        """Get the equivalent namespace client for this connection.
+
+        For native storage connections, this returns a DirectoryNamespace
+        pointing to the same root with the same storage options.
+
+        For namespace connections, this returns the backing namespace client.
+
+        For enterprise (remote) connections, this returns a RestNamespace
+        with the same URI and authentication headers.
+
+        Returns
+        -------
+        LanceNamespace
+            The namespace client for this connection.
+        """
+        raise NotImplementedError(
+            "namespace_client is not supported for this connection type"
+        )
+
 
 class LanceDBConnection(DBConnection):
     """
@@ -1044,6 +1066,20 @@ class LanceDBConnection(DBConnection):
             )
         )
 
+    @override
+    def namespace_client(self) -> LanceNamespace:
+        """Get the equivalent namespace client for this connection.
+
+        Returns a DirectoryNamespace pointing to the same root with the
+        same storage options.
+
+        Returns
+        -------
+        LanceNamespace
+            The namespace client for this connection.
+        """
+        return LOOP.run(self._conn.namespace_client())
+
     @deprecation.deprecated(
         deprecated_in="0.15.1",
         removed_in="0.17",
@@ -1716,6 +1752,25 @@ class AsyncConnection(object):
             namespace_path = []
         await self._inner.drop_all_tables(namespace_path=namespace_path)
 
+    async def namespace_client(self) -> LanceNamespace:
+        """Get the equivalent namespace client for this connection.
+
+        For native storage connections, this returns a DirectoryNamespace
+        pointing to the same root with the same storage options.
+
+        For namespace connections, this returns the backing namespace client.
+
+        For enterprise (remote) connections, this returns a RestNamespace
+        with the same URI and authentication headers.
+
+        Returns
+        -------
+        LanceNamespace
+            The namespace client for this connection.
+        """
+        config = await self._inner.namespace_client_config()
+        return namespace_connect(config["impl"], config["properties"])
+
     @deprecation.deprecated(
         deprecated_in="0.15.1",
         removed_in="0.17",

python/python/lancedb/namespace.py

@@ -890,6 +890,20 @@ class LanceNamespaceDBConnection(DBConnection):
             pushdown_operations=self._pushdown_operations,
         )
 
+    @override
+    def namespace_client(self) -> LanceNamespace:
+        """Get the namespace client for this connection.
+
+        For namespace connections, this returns the backing namespace client
+        that was provided during construction.
+
+        Returns
+        -------
+        LanceNamespace
+            The namespace client for this connection.
+        """
+        return self._namespace_client
+
 
 class AsyncLanceNamespaceDBConnection:
     """
@@ -1387,6 +1401,19 @@ class AsyncLanceNamespaceDBConnection:
             page_token=response.page_token,
         )
 
+    async def namespace_client(self) -> LanceNamespace:
+        """Get the namespace client for this connection.
+
+        For namespace connections, this returns the backing namespace client
+        that was provided during construction.
+
+        Returns
+        -------
+        LanceNamespace
+            The namespace client for this connection.
+        """
+        return self._namespace_client
+
 
 def connect_namespace(
     namespace_client_impl: str,

python/python/lancedb/remote/db.py

@@ -24,6 +24,7 @@ from ..common import DATA
 from ..db import DBConnection, LOOP
 from ..embeddings import EmbeddingFunctionConfig
 from lance_namespace import (
+    LanceNamespace,
     CreateNamespaceResponse,
     DescribeNamespaceResponse,
     DropNamespaceResponse,
@@ -570,6 +571,19 @@ class RemoteDBConnection(DBConnection):
             )
         )
 
+    @override
+    def namespace_client(self) -> LanceNamespace:
+        """Get the equivalent namespace client for this connection.
+
+        Returns a RestNamespace with the same URI and authentication headers.
+
+        Returns
+        -------
+        LanceNamespace
+            The namespace client for this connection.
+        """
+        return LOOP.run(self._conn.namespace_client())
+
     async def close(self):
         """Close the connection to the database."""
         self._conn.close()

python/python/tests/test_db.py

@@ -1048,3 +1048,57 @@ def test_clone_table_deep_clone_fails(tmp_path):
     source_uri = os.path.join(tmp_path, "source.lance")
     with pytest.raises(Exception, match="Deep clone is not yet implemented"):
         db.clone_table("cloned", source_uri, is_shallow=False)
+
+
+def test_namespace_client_native_storage(tmp_path):
+    """Test namespace_client() returns DirectoryNamespace for native storage connections."""
+    from lance.namespace import DirectoryNamespace
+
+    db = lancedb.connect(tmp_path)
+    ns_client = db.namespace_client()
+
+    assert isinstance(ns_client, DirectoryNamespace)
+    assert str(tmp_path) in ns_client.namespace_id()
+
+
+def test_namespace_client_with_storage_options(tmp_path):
+    """Test namespace_client() preserves storage options."""
+    from lance.namespace import DirectoryNamespace
+
+    storage_options = {"timeout": "10s"}
+    db = lancedb.connect(tmp_path, storage_options=storage_options)
+    ns_client = db.namespace_client()
+
+    assert isinstance(ns_client, DirectoryNamespace)
+
+
+def test_namespace_client_operations(tmp_path):
+    """Test that namespace_client() returns a functional namespace client."""
+    db = lancedb.connect(tmp_path)
+    ns_client = db.namespace_client()
+
+    # Create a table through the main db connection
+    data = [{"id": 1, "text": "hello", "vector": [1.0, 2.0]}]
+    db.create_table("test_table", data=data)
+
+    # Verify the namespace client can see the table
+    from lance_namespace import ListTablesRequest
+
+    # id=[] means root namespace
+    response = ns_client.list_tables(ListTablesRequest(id=[]))
+    # Tables can be strings or objects with name attribute
+    table_names = [
+        t.name if hasattr(t, "name") else t for t in response.tables
+    ]
+    assert "test_table" in table_names
+
+
+def test_namespace_client_namespace_connection(tmp_path):
+    """Test namespace_client() returns the backing client for namespace connections."""
+    from lance.namespace import DirectoryNamespace
+
+    db = lancedb.connect_namespace("dir", {"root": str(tmp_path)})
+    ns_client = db.namespace_client()
+
+    assert isinstance(ns_client, DirectoryNamespace)
+    assert str(tmp_path) in ns_client.namespace_id()

python/src/connection.rs

@@ -474,6 +474,25 @@ impl Connection {
             })
         })
     }
+
+    /// Get the configuration for constructing an equivalent namespace client.
+    /// Returns a dict with:
+    /// - "impl": "dir" for DirectoryNamespace, "rest" for RestNamespace
+    /// - "properties": configuration properties for the namespace
+    #[pyo3(signature = ())]
+    pub fn namespace_client_config(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
+        let inner = self_.get_inner()?.clone();
+        let py = self_.py();
+        future_into_py(py, async move {
+            let (impl_type, properties) = inner.namespace_client_config().await.infer_error()?;
+            Python::attach(|py| -> PyResult<Py<PyDict>> {
+                let dict = PyDict::new(py);
+                dict.set_item("impl", impl_type)?;
+                dict.set_item("properties", properties)?;
+                Ok(dict.unbind())
+            })
+        })
+    }
 }
 
 #[pyfunction]