From 623b321e757669366a1b1861a6975869c05ecc15 Mon Sep 17 00:00:00 2001
From: c-bata <c-bata@users.noreply.github.com>
Date: Sat, 22 Jul 2023 00:39:36 +0900
Subject: [PATCH] Fix `allowed_search_types` in `VectorStoreRetriever` (#8064)

Unexpectedly changed at
https://github.com/hwchase17/langchain/commit/6792a3557dc396804a12ba8892b36a322434c7c6

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I guess `allowed_search_types` is unexpectedly changed in
https://github.com/hwchase17/langchain/commit/6792a3557dc396804a12ba8892b36a322434c7c6,
so that we cannot specify `similarity_score_threshold` here.

```python
class VectorStoreRetriever(BaseRetriever):
    ...
    allowed_search_types: ClassVar[Collection[str]] = (
        "similarity",
        "similarityatscore_threshold",
        "mmr",
    )

    @root_validator()
    def validate_search_type(cls, values: Dict) -> Dict:
        """Validate search type."""
        search_type = values["search_type"]
        if search_type not in cls.allowed_search_types:
            raise ValueError(...)
        if search_type == "similarity_score_threshold":
            ... # UNREACHABLE CODE
```

VectorStores Maintainers: @rlancemartin @eyurtsev
---
 langchain/vectorstores/base.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/langchain/vectorstores/base.py b/langchain/vectorstores/base.py
index 8e04645222..4911c87a66 100644
--- a/langchain/vectorstores/base.py
+++ b/langchain/vectorstores/base.py
@@ -465,7 +465,7 @@ class VectorStoreRetriever(BaseRetriever):
     search_kwargs: dict = Field(default_factory=dict)
     allowed_search_types: ClassVar[Collection[str]] = (
         "similarity",
-        "similarityatscore_threshold",
+        "similarity_score_threshold",
         "mmr",
     )