Make Milvus storage backend opt-in (storage-milvus group)

common/storage/milvus/README.md

@@ -2,6 +2,12 @@
 
 This module implements vector database storage using Milvus for the vCon server.
 
+> **Optional dependency.** `pymilvus` (which pulls in pandas + grpcio, ~85MB the
+> rest of vcon-server does not use) is **not** part of the base `storage` group.
+> Install it explicitly to use this backend:
+> `uv sync --group storage --group storage-milvus`. Without it, importing
+> `storage.milvus` will fail with `ImportError`/`ModuleNotFoundError` due to the missing dependency.
+
 ## Overview
 
 Milvus storage provides high-performance vector similarity search capabilities, ideal for storing and retrieving vector embeddings of vCon data. It's particularly useful for semantic search and similarity matching applications.

common/storage/milvus/test_milvus.py

@@ -1,6 +1,11 @@
 import pytest
 from unittest.mock import patch, MagicMock, mock_open
 
+# pymilvus/openai are optional dependencies (group: storage-milvus). storage.milvus
+# imports them at module load, so skip this whole module when they aren't installed.
+pytest.importorskip("pymilvus")
+pytest.importorskip("openai")
+
 from lib.vcon_redis import VconRedis
 from vcon import Vcon
 from storage.milvus import (

common/storage/milvus/test_milvus_branches.py

@@ -2,6 +2,11 @@
 
 import pytest
 
+# pymilvus/openai are optional dependencies (group: storage-milvus). storage.milvus
+# imports them at module load, so skip this whole module when they aren't installed.
+pytest.importorskip("pymilvus")
+pytest.importorskip("openai")
+
 from storage import milvus as milvus_module
 from storage.milvus import (
     check_vcon_exists,

docker/Dockerfile

@@ -29,9 +29,11 @@ COPY pyproject.toml uv.lock /app/
 
 # Install all groups (conserver + api + dev) so the image works for both
 # running services and running pytest.
+# storage-milvus is included here (but NOT in the production Dockerfile.conserver /
+# Dockerfile.api images) so the Milvus storage tests run in CI rather than skip.
 # Venv at /opt/venv so docker-compose volume mounts don't wipe it.
 RUN uv venv --seed /opt/venv && \
-    UV_PROJECT_ENVIRONMENT=/opt/venv uv sync --frozen --group conserver --group api --group dev
+    UV_PROJECT_ENVIRONMENT=/opt/venv uv sync --frozen --group conserver --group api --group dev --group storage-milvus
 ENV PATH="/opt/venv/bin:$PATH"
 
 # Auto-install OTel instrumentation packages for the installed libraries.

pyproject.toml

@@ -34,13 +34,23 @@ dependencies = [
 storage = [
     "pymongo>=4.7.2",
     "elasticsearch>=8.13.1,<9.0.0",
-    "pymilvus>=2.3.0",
     "msal>=1.32.3",
     "boto3>=1.34.52",
     "psycopg2-binary>=2.9.9",
     "peewee>=3.17.1",
 ]
 
+# Optional: Milvus vector-database storage backend (storage.milvus).
+# pymilvus drags in pandas (~48MB) and grpcio (~37MB), neither of which the
+# rest of vcon-server uses, so it is kept out of the base `storage` group.
+# Includes openai for the embedding calls the backend makes. Only installs
+# pymilvus when explicitly requested; storage.milvus raises a clear ImportError
+# otherwise. Install with: uv sync --group storage --group storage-milvus
+storage-milvus = [
+    "pymilvus>=2.3.0",
+    "openai>=1.60.0",
+]
+
 # API service dependencies — HTTP layer and API key management.
 # Install with: uv sync --group api
 api = [