community[patch]: vectorstores import update (#21169)

Issue: we have several helper functions to import third-party libraries
like lancedb.import_lancedb in
[community.vectorstores](https://api.python.langchain.com/en/latest/vectorstores/langchain_community.vectorstores.lancedb.import_lancedb.html#langchain_community.vectorstores.lancedb.import_lancedb).
And we have core.utils.utils.guard_import that works exactly for this
purpose.
The import_<package> functions work inconsistently and rather be private
functions.
Change: replaced these functions with the guard_import function.

Related to #21133

libs/community/langchain_community/vectorstores/tiledb.py

@@ -1,4 +1,5 @@
 """Wrapper around TileDB vector database."""
+
 from __future__ import annotations
 
 import pickle
@@ -9,6 +10,7 @@ from typing import Any, Dict, Iterable, List, Mapping, Optional, Tuple
 import numpy as np
 from langchain_core.documents import Document
 from langchain_core.embeddings import Embeddings
+from langchain_core.utils import guard_import
 from langchain_core.vectorstores import VectorStore
 
 from langchain_community.vectorstores.utils import maximal_marginal_relevance
@@ -24,16 +26,10 @@ MAX_FLOAT = sys.float_info.max
 
 def dependable_tiledb_import() -> Any:
     """Import tiledb-vector-search if available, otherwise raise error."""
-    try:
-        import tiledb as tiledb
-        import tiledb.vector_search as tiledb_vs
-    except ImportError:
-        raise ImportError(
-            "Could not import tiledb-vector-search python package. "
-            "Please install it with `conda install -c tiledb tiledb-vector-search` "
-            "or `pip install tiledb-vector-search`"
-        )
-    return tiledb_vs, tiledb
+    return (
+        guard_import("tiledb.vector_search"),
+        guard_import("tiledb"),
+    )
 
 
 def get_vector_index_uri_from_group(group: Any) -> str:
@@ -115,7 +111,10 @@ class TileDB(VectorStore):
         self.metric = metric
         self.config = config
 
-        tiledb_vs, tiledb = dependable_tiledb_import()
+        tiledb_vs, tiledb = (
+            guard_import("tiledb.vector_search"),
+            guard_import("tiledb"),
+        )
         with tiledb.scope_ctx(ctx_or_config=config):
             index_group = tiledb.Group(self.index_uri, "r")
             self.vector_index_uri = (
@@ -173,7 +172,7 @@ class TileDB(VectorStore):
         Returns:
             List of Documents and scores.
         """
-        tiledb_vs, tiledb = dependable_tiledb_import()
+        tiledb = guard_import("tiledb")
         docs = []
         docs_array = tiledb.open(
             self.docs_array_uri, "r", timestamp=self.timestamp, config=self.config
@@ -477,7 +476,10 @@ class TileDB(VectorStore):
         metadatas: bool = True,
         config: Optional[Mapping[str, Any]] = None,
     ) -> None:
-        tiledb_vs, tiledb = dependable_tiledb_import()
+        tiledb_vs, tiledb = (
+            guard_import("tiledb.vector_search"),
+            guard_import("tiledb"),
+        )
         with tiledb.scope_ctx(ctx_or_config=config):
             try:
                 tiledb.group_create(index_uri)
@@ -550,7 +552,10 @@ class TileDB(VectorStore):
                     f"Expected one of {list(INDEX_METRICS)}"
                 )
             )
-        tiledb_vs, tiledb = dependable_tiledb_import()
+        tiledb_vs, tiledb = (
+            guard_import("tiledb.vector_search"),
+            guard_import("tiledb"),
+        )
         input_vectors = np.array(embeddings).astype(np.float32)
         cls.create(
             index_uri=index_uri,
@@ -646,7 +651,7 @@ class TileDB(VectorStore):
         Returns:
             List of ids from adding the texts into the vectorstore.
         """
-        tiledb_vs, tiledb = dependable_tiledb_import()
+        tiledb = guard_import("tiledb")
         embeddings = self.embedding.embed_documents(list(texts))
         if ids is None:
             ids = [str(random.randint(0, MAX_UINT64 - 1)) for _ in texts]