feat(storage): add ChromaDB and LanceDB vector backends

pyproject.toml

@@ -36,6 +36,8 @@ dependencies = [
 postgres = ["asyncpg>=0.29", "pgvector>=0.2"]
 neo4j = ["neo4j>=5.14"]
 qdrant = ["qdrant-client>=1.7"]
+chroma = ["chromadb>=0.4"]
+lancedb = ["lancedb>=0.5", "pyarrow>=14"]
 anthropic = ["anthropic>=0.20", "voyageai>=0.2"]
 sentence-transformers = ["sentence-transformers>=2.6"]
 bge = ["FlagEmbedding>=1.2"]

tests/integration/test_chroma_backend.py

@@ -0,0 +1,267 @@
+"""Integration tests for ChromaBackend — uses EphemeralClient (no server needed).
+
+Tests are skipped automatically when chromadb is not installed.
+"""
+
+from __future__ import annotations
+
+import pytest
+
+
+def _is_chroma_available() -> bool:
+    try:
+        import chromadb  # noqa: F401
+
+        return True
+    except ImportError:
+        return False
+
+
+@pytest.fixture
+async def chroma_backend():
+    if not _is_chroma_available():
+        pytest.skip("chromadb not installed")
+
+    from vektori.storage.chroma_backend import ChromaBackend
+
+    # EphemeralClient (in-memory, no disk) — path=None, host=None
+    backend = ChromaBackend(prefix="test", embedding_dim=4)
+    await backend.initialize()
+    yield backend
+    await backend.delete_user("test-user")
+    await backend.delete_user("delete-test-user")
+    await backend.close()
+
+
+# ── Sentences ──────────────────────────────────────────────────────────────────
+
+
+async def test_upsert_and_search_sentences(chroma_backend):
+    emb = [0.1, 0.2, 0.3, 0.4]
+    sentences = [
+        {
+            "id": "cs1",
+            "text": "I love hiking in the mountains.",
+            "session_id": "csess1",
+            "turn_number": 0,
+            "sentence_index": 0,
+            "role": "user",
+        }
+    ]
+    count = await chroma_backend.upsert_sentences(sentences, [emb], user_id="test-user")
+    assert count == 1
+
+    results = await chroma_backend.search_sentences(emb, user_id="test-user", limit=5)
+    assert len(results) >= 1
+    assert results[0]["text"] == "I love hiking in the mountains."
+    assert "distance" in results[0]
+
+
+async def test_sentence_dedup_increments_mentions(chroma_backend):
+    emb = [0.2, 0.3, 0.4, 0.5]
+    sent = [
+        {
+            "id": "cs-dedup",
+            "text": "I enjoy running.",
+            "session_id": "csess2",
+            "turn_number": 1,
+            "sentence_index": 0,
+            "role": "user",
+        }
+    ]
+    await chroma_backend.upsert_sentences(sent, [emb], user_id="test-user")
+    await chroma_backend.upsert_sentences(sent, [emb], user_id="test-user")
+
+    results = await chroma_backend.search_sentences(emb, user_id="test-user", limit=5)
+    match = next((r for r in results if r["id"] == "cs-dedup"), None)
+    assert match is not None
+    assert match["mentions"] == 2
+
+
+async def test_find_sentence_containing(chroma_backend):
+    emb = [0.3, 0.4, 0.5, 0.6]
+    sent = [
+        {
+            "id": "cs-find",
+            "text": "The weather is sunny today.",
+            "session_id": "csess3",
+            "turn_number": 0,
+            "sentence_index": 0,
+            "role": "user",
+        }
+    ]
+    await chroma_backend.upsert_sentences(sent, [emb], user_id="test-user")
+
+    result = await chroma_backend.find_sentence_containing("csess3", "sunny")
+    assert result is not None
+    assert result["id"] == "cs-find"
+
+    none_result = await chroma_backend.find_sentence_containing("csess3", "rainy")
+    assert none_result is None
+
+
+# ── Facts ──────────────────────────────────────────────────────────────────────
+
+
+async def test_insert_and_search_facts(chroma_backend):
+    emb = [0.1, 0.2, 0.3, 0.4]
+    fact_id = await chroma_backend.insert_fact(
+        text="User prefers Python over Java.",
+        embedding=emb,
+        user_id="test-user",
+        subject="language",
+    )
+    assert fact_id
+
+    results = await chroma_backend.search_facts(emb, user_id="test-user", limit=5)
+    assert len(results) >= 1
+    match = next((r for r in results if r["id"] == fact_id), None)
+    assert match is not None
+    assert match["text"] == "User prefers Python over Java."
+    assert match["subject"] == "language"
+    assert "distance" in match
+
+
+async def test_deactivate_fact_with_supersession(chroma_backend):
+    emb = [0.2, 0.3, 0.4, 0.5]
+    old_id = await chroma_backend.insert_fact(
+        text="User lives in NYC.", embedding=emb, user_id="test-user"
+    )
+    new_id = await chroma_backend.insert_fact(
+        text="User lives in SF.", embedding=emb, user_id="test-user"
+    )
+    await chroma_backend.deactivate_fact(old_id, superseded_by=new_id)
+
+    active = await chroma_backend.get_active_facts("test-user")
+    ids = [f["id"] for f in active]
+    assert old_id not in ids
+    assert new_id in ids
+
+
+async def test_increment_fact_mentions(chroma_backend):
+    emb = [0.3, 0.4, 0.5, 0.6]
+    fact_id = await chroma_backend.insert_fact(
+        text="User likes tea.", embedding=emb, user_id="test-user"
+    )
+    await chroma_backend.increment_fact_mentions(fact_id)
+    await chroma_backend.increment_fact_mentions(fact_id)
+
+    active = await chroma_backend.get_active_facts("test-user")
+    match = next((f for f in active if f["id"] == fact_id), None)
+    assert match is not None
+    assert match["mentions"] == 3
+
+
+async def test_find_fact_by_text(chroma_backend):
+    emb = [0.4, 0.5, 0.6, 0.7]
+    await chroma_backend.insert_fact(text="User is vegetarian.", embedding=emb, user_id="test-user")
+    found = await chroma_backend.find_fact_by_text("test-user", "vegetarian")
+    assert found is not None
+    assert "vegetarian" in found["text"]
+
+
+# ── Episodes ──────────────────────────────────────────────────────────────────
+
+
+async def test_insert_and_search_episodes(chroma_backend):
+    emb = [0.1, 0.2, 0.3, 0.4]
+    ep_id = await chroma_backend.insert_episode(
+        text="User discussed travel plans.",
+        embedding=emb,
+        user_id="test-user",
+        session_id="csess4",
+    )
+    assert ep_id
+
+    # Idempotent insert
+    ep_id2 = await chroma_backend.insert_episode(
+        text="User discussed travel plans.",
+        embedding=emb,
+        user_id="test-user",
+        session_id="csess4",
+    )
+    assert ep_id == ep_id2
+
+    results = await chroma_backend.search_episodes(emb, user_id="test-user", limit=5)
+    assert any(r["id"] == ep_id for r in results)
+
+
+async def test_episode_fact_link(chroma_backend):
+    emb = [0.2, 0.3, 0.4, 0.5]
+    ep_id = await chroma_backend.insert_episode(
+        text="User likes outdoor activities.",
+        embedding=emb,
+        user_id="test-user",
+    )
+    fact_id = await chroma_backend.insert_fact(
+        text="User goes hiking weekly.", embedding=emb, user_id="test-user"
+    )
+    await chroma_backend.insert_episode_fact(ep_id, fact_id)
+
+    episodes = await chroma_backend.get_episodes_for_facts([fact_id])
+    assert any(e["id"] == ep_id for e in episodes)
+
+
+# ── Join tables ────────────────────────────────────────────────────────────────
+
+
+async def test_fact_source_sentences(chroma_backend):
+    emb = [0.1, 0.2, 0.3, 0.4]
+    sent = [
+        {
+            "id": "cs-src1",
+            "text": "I go to the gym every morning.",
+            "session_id": "csess5",
+            "turn_number": 0,
+            "sentence_index": 0,
+            "role": "user",
+        }
+    ]
+    await chroma_backend.upsert_sentences(sent, [emb], user_id="test-user")
+    fact_id = await chroma_backend.insert_fact(
+        text="User exercises daily.", embedding=emb, user_id="test-user"
+    )
+    await chroma_backend.insert_fact_source(fact_id, "cs-src1")
+
+    sources = await chroma_backend.get_source_sentences([fact_id])
+    assert "cs-src1" in sources
+
+
+# ── Sessions ───────────────────────────────────────────────────────────────────
+
+
+async def test_upsert_and_get_session(chroma_backend):
+    await chroma_backend.upsert_session(
+        session_id="csess-get",
+        user_id="test-user",
+        metadata={"source": "test"},
+    )
+    session = await chroma_backend.get_session("csess-get", "test-user")
+    assert session is not None
+    assert session["user_id"] == "test-user"
+    assert session["sentences"] == []
+
+    # Wrong user returns None
+    assert await chroma_backend.get_session("csess-get", "other-user") is None
+
+
+async def test_count_sessions(chroma_backend):
+    before = await chroma_backend.count_sessions("test-user")
+    await chroma_backend.upsert_session("csess-cnt1", "test-user")
+    await chroma_backend.upsert_session("csess-cnt2", "test-user")
+    after = await chroma_backend.count_sessions("test-user")
+    assert after == before + 2
+
+
+# ── GDPR ───────────────────────────────────────────────────────────────────────
+
+
+async def test_delete_user(chroma_backend):
+    emb = [0.1, 0.2, 0.3, 0.4]
+    await chroma_backend.upsert_session("csess-del", "delete-test-user")
+    await chroma_backend.insert_fact(text="Delete me.", embedding=emb, user_id="delete-test-user")
+    deleted = await chroma_backend.delete_user("delete-test-user")
+    assert deleted >= 2
+
+    active = await chroma_backend.get_active_facts("delete-test-user")
+    assert active == []