feat: add list_indices to the async api (#1074)

python/python/lancedb/_lancedb.pyi

@@ -1,4 +1,4 @@
-from typing import Dict, Optional
+from typing import Dict, List, Optional
 
 import pyarrow as pa
 
@@ -39,6 +39,11 @@ class Table:
     async def checkout(self, version): ...
     async def checkout_latest(self): ...
     async def restore(self): ...
+    async def list_indices(self) -> List[IndexConfig]: ...
+
+class IndexConfig:
+    index_type: str
+    columns: List[str]
 
 async def connect(
     uri: str,

python/python/lancedb/index.py

@@ -3,6 +3,9 @@ from typing import Optional
 from ._lancedb import (
     Index as LanceDbIndex,
 )
+from ._lancedb import (
+    IndexConfig,
+)
 
 
 class BTree(object):
@@ -155,3 +158,6 @@ class IvfPq(object):
             max_iterations=max_iterations,
             sample_rate=sample_rate,
         )
+
+
+__all__ = ["BTree", "IvfPq", "IndexConfig"]

python/python/lancedb/table.py

@@ -59,7 +59,7 @@ if TYPE_CHECKING:
 
     from ._lancedb import Table as LanceDBTable
     from .db import LanceDBConnection
-    from .index import BTree, IvfPq
+    from .index import BTree, IndexConfig, IvfPq
 
 
 pd = safe_import_pandas()
@@ -2409,3 +2409,9 @@ class AsyncTable:
         out state and the read_consistency_interval, if any, will apply.
         """
         await self._inner.restore()
+
+    async def list_indices(self) -> IndexConfig:
+        """
+        List all indices that have been created with Self::create_index
+        """
+        return await self._inner.list_indices()

python/python/tests/test_index.py

@@ -41,6 +41,10 @@ async def test_create_scalar_index(some_table: AsyncTable):
     await some_table.create_index("id")
     # Can recreate if replace=True
     await some_table.create_index("id", replace=True)
+    indices = await some_table.list_indices()
+    assert len(indices) == 1
+    assert indices[0].index_type == "BTree"
+    assert indices[0].columns == ["id"]
     # Can't recreate if replace=False
     with pytest.raises(RuntimeError, match="already exists"):
         await some_table.create_index("id", replace=False)
@@ -59,3 +63,7 @@ async def test_create_vector_index(some_table: AsyncTable):
         await some_table.create_index("vector", replace=False)
     # Can also specify index type
     await some_table.create_index("vector", config=IvfPq(num_partitions=100))
+    indices = await some_table.list_indices()
+    assert len(indices) == 1
+    assert indices[0].index_type == "IvfPq"
+    assert indices[0].columns == ["vector"]