fix(adapter): close final foundation review

harness/tests/test_adapter_factory.py

@@ -6,7 +6,7 @@ from tht.adapters.factory import build_dwh, build_vector_store
 from tht.config import Config, ConfigError
 
 
-def _config(*, dwh_type="thoth_rest", vector_type="thoth_vector_http", writer=True):
+def _config(*, dwh_type="thoth_rest", vector_type="thoth_vector_http", reader=True, writer=True):
     dwh = (
         {
             "type": "thoth_rest",
@@ -28,7 +28,7 @@ def _config(*, dwh_type="thoth_rest", vector_type="thoth_vector_http", writer=Tr
     vectors = (
         {
             "type": "thoth_vector_http",
-            "reader": {"base_url": "https://vectors.test/", "api_key": "reader"},
+            **({"reader": {"base_url": "https://vectors.test/", "api_key": "reader"}} if reader else {}),
             **(
                 {"writer": {"base_url": "https://vectors.test/", "api_key": "writer"}}
                 if writer
@@ -78,6 +78,15 @@ def test_factory_selects_http_vector_and_requires_writer():
         build_vector_store(config, require_write=True)
 
 
+def test_factory_builds_writer_only_http_vector_when_write_is_required():
+    config = _config(reader=False, writer=True)
+
+    store = build_vector_store(config, require_write=True)
+    assert isinstance(store, ThothHttpVectorStore)
+    assert store.capabilities.search is False
+    assert store.capabilities.upsert is True
+
+
 def test_factory_selects_direct_vector_reader():
     config = _config(vector_type="pgvector_direct")