From 73a628de9a56b45d99f2696a5b38fcca8434545b Mon Sep 17 00:00:00 2001
From: suhas-kotaki <136513875+suhas-kotaki@users.noreply.github.com>
Date: Tue, 2 Jan 2024 14:59:53 -0800
Subject: [PATCH] added fix for key error: doc_id (#15428)

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---
 libs/langchain/langchain/retrievers/multi_vector.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libs/langchain/langchain/retrievers/multi_vector.py b/libs/langchain/langchain/retrievers/multi_vector.py
index 9b58a091f60..bfb21af80ce 100644
--- a/libs/langchain/langchain/retrievers/multi_vector.py
+++ b/libs/langchain/langchain/retrievers/multi_vector.py
@@ -67,7 +67,7 @@ class MultiVectorRetriever(BaseRetriever):
         # We do this to maintain the order of the ids that are returned
         ids = []
         for d in sub_docs:
-            if d.metadata[self.id_key] not in ids:
+            if self.id_key in d.metadata and d.metadata[self.id_key] not in ids:
                 ids.append(d.metadata[self.id_key])
         docs = self.docstore.mget(ids)
         return [d for d in docs if d is not None]