unable to use milvus for cosine similarity

[pierowu]

Checked other resources

• I added a very descriptive title to this issue.
• I searched the LangChain documentation with the integrated search.
• I used the GitHub search to find a similar question and didn't find it.
• I am sure that this is a bug in LangChain rather than my code.
• The bug is not resolved by updating to the latest stable version of LangChain (or the specific integration package).

Example Code

The following code:
URI = "./milvus_example.db"
index_params = {
'metric_type': 'COSINE',
'index_type': "FLAT",
# 'params': {"nlist": 128}
}
search_params = {
"metric_type": "COSINE",
# "params": {"nprobe": 12},
}

vector_store = Milvus(
embedding_function=embeddings,
connection_args={"uri": URI},
auto_id=True,
index_params=index_params,
search_params=search_params
)
all_splits = text_splitter.split_documents(documents)
ids = vector_store.add_documents(documents=all_splits)
results = vector_store.similarity_search_with_score(prompt,param=search_params)

Error Message and Stack Trace (if applicable)

RPC error: [search], <MilvusException: (code=1100, message=fail to search: metric type not match: invalid [expected=L2][actual=COSINE]: invalid parameter)>, <Time:{'RPC start': '2024-12-25 16:15:58.358832', 'RPC error': '2024-12-25 16:15:58.359751'}>
0%| | 0/1174 [00:01<?, ?it/s]
Traceback (most recent call last):
File "/home/wupeiyang/work/RTL-Repo/src/generate_data_for_rag_test_dynamic_langchain.py", line 405, in
main()
File "/home/wupeiyang/work/RTL-Repo/src/generate_data_for_rag_test_dynamic_langchain.py", line 306, in main
results = vector_store.similarity_search_with_score(prompt,param=search_params)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/langchain_milvus/vectorstores/milvus.py", line 1182, in similarity_search_with_score
res = self.similarity_search_with_score_by_vector(
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/langchain_milvus/vectorstores/milvus.py", line 1221, in similarity_search_with_score_by_vector
col_search_res = self._collection_search(
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/langchain_milvus/vectorstores/milvus.py", line 1047, in _collection_search
res = self.col.search(
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/orm/collection.py", line 801, in search
resp = conn.search(
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/decorators.py", line 141, in handler
raise e from e
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/decorators.py", line 137, in handler
return func(*args, **kwargs)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/decorators.py", line 176, in handler
return func(self, *args, **kwargs)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/decorators.py", line 116, in handler
raise e from e
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/decorators.py", line 86, in handler
return func(*args, **kwargs)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/client/grpc_handler.py", line 805, in search
return self._execute_search(request, timeout, round_decimal=round_decimal, **kwargs)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/client/grpc_handler.py", line 746, in _execute_search
raise e from e
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/client/grpc_handler.py", line 735, in _execute_search
check_status(response.status)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/pymilvus/client/utils.py", line 63, in check_status
raise MilvusException(status.code, status.reason, status.error_code)
pymilvus.exceptions.MilvusException: <MilvusException: (code=1100, message=fail to search: metric type not match: invalid [expected=L2][actual=COSINE]: invalid parameter)>
[2024-12-25 16:16:03,525] torch.distributed.elastic.multiprocessing.api: [ERROR] failed (exitcode: 1) local_rank: 0 (pid: 29719) of binary: /home-g2/wupeiyang/anaconda3/envs/llama3/bin/python
Traceback (most recent call last):
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/runpy.py", line 197, in _run_module_as_main
return _run_code(code, main_globals, None,
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/runpy.py", line 87, in _run_code
exec(code, run_globals)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/torch/distributed/launch.py", line 196, in
main()
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/torch/distributed/launch.py", line 192, in main
launch(args)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/torch/distributed/launch.py", line 177, in launch
run(args)
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/torch/distributed/run.py", line 797, in run
elastic_launch(
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/torch/distributed/launcher/api.py", line 134, in call
return launch_agent(self._config, self._entrypoint, list(args))
File "/home-g2/wupeiyang/anaconda3/envs/llama3/lib/python3.9/site-packages/torch/distributed/launcher/api.py", line 264, in launch_agent
raise ChildFailedError(
torch.distributed.elastic.multiprocessing.errors.ChildFailedError:

/home/wupeiyang/work/RTL-Repo/src/generate_data_for_rag_test_dynamic_langchain.py FAILED

Failures:
<NO_OTHER_FAILURES>

Root Cause (first observed failure):
[0]:
time : 2024-12-25_16:16:03
host : localhost
rank : 0 (local_rank: 0)
exitcode : 1 (pid: 29719)
error_file: <N/A>
traceback : To enable traceback see: https://pytorch.org/docs/stable/elastic/errors.html

Description

I'm trying to use langchain_milvus to search by cosine similarity which is supported according to Milvus Doc

System Info

System Information

OS: Linux
OS Version: #224-Ubuntu SMP Thu Dec 5 13:38:28 UTC 2024
Python Version: 3.9.18 (main, Sep 11 2023, 13:41:44)
[GCC 11.2.0]

Package Information

langchain_core: 0.3.21
langchain: 0.3.9
langchain_community: 0.3.9
langsmith: 0.1.147
langchain_huggingface: 0.1.2
langchain_milvus: 0.1.7
langchain_ollama: 0.2.1
langchain_text_splitters: 0.3.2

Optional packages not installed

langserve

Other Dependencies

aiohttp: 3.9.1
async-timeout: 4.0.3
dataclasses-json: 0.6.7
httpx: 0.27.0
httpx-sse: 0.4.0
huggingface-hub: 0.23.3
jsonpatch: 1.33
langsmith-pyo3: Installed. No version info available.
numpy: 1.26.3
ollama: 0.4.2
orjson: 3.10.12
packaging: 23.2
pydantic: 2.10.2
pydantic-settings: 2.6.1
pymilvus: 2.5.0
PyYAML: 6.0.1
requests: 2.31.0
requests-toolbelt: 1.0.0
sentence-transformers: 3.3.1
SQLAlchemy: 2.0.36
tenacity: 9.0.0
tokenizers: 0.19.1
transformers: 4.41.2
typing-extensions: 4.12.2