langchain[patch]: support ollama in init_embeddings (#29349)

Why not Ollama ?

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---------

Co-authored-by: Chester Curme <[email protected]>

libs/langchain/langchain/embeddings/base.py

@@ -13,6 +13,7 @@
     "google_vertexai": "langchain_google_vertexai",
     "huggingface": "langchain_huggingface",
     "mistralai": "langchain_mistralai",
+    "ollama": "langchain_ollama",
     "openai": "langchain_openai",
 }
 
@@ -209,6 +210,10 @@ def init_embeddings(
         from langchain_huggingface import HuggingFaceEmbeddings
 
         return HuggingFaceEmbeddings(model_name=model_name, **kwargs)
+    elif provider == "ollama":
+        from langchain_ollama import OllamaEmbeddings
+
+        return OllamaEmbeddings(model=model_name, **kwargs)
     else:
         raise ValueError(
             f"Provider '{provider}' is not supported.\n"