perf(core): reuse written note content after writes

src/basic_memory/api/v2/routers/knowledge_router.py

@@ -306,8 +306,11 @@ async def create_entity(
         ):
             if fast:
                 entity = await entity_service.fast_write_entity(data)
+                written_content = None
             else:
-                entity = await entity_service.create_entity(data)
+                write_result = await entity_service.create_entity_with_content(data)
+                entity = write_result.entity
+                written_content = write_result.content
 
         if fast:
             with telemetry.scope(
@@ -329,7 +332,7 @@ async def create_entity(
                 action="create_entity",
                 phase="search_index",
             ):
-                await search_service.index_entity(entity)
+                await search_service.index_entity(entity, content=written_content)
             with telemetry.scope(
                 "api.knowledge.create_entity.vector_sync",
                 domain="knowledge",
@@ -352,8 +355,12 @@ async def create_entity(
             domain="knowledge",
             action="create_entity",
             phase="read_content",
+            source="file" if fast else "memory",
         ):
-            content = await file_service.read_file_content(entity.file_path)
+            if fast:
+                content = await file_service.read_file_content(entity.file_path)
+            else:
+                content = written_content
         result = result.model_copy(update={"content": content})
 
         logger.info(
@@ -421,13 +428,18 @@ async def update_entity_by_id(
         ):
             if fast:
                 entity = await entity_service.fast_write_entity(data, external_id=entity_id)
+                written_content = None
                 response.status_code = 200 if existing else 201
             else:
                 if existing:
-                    entity = await entity_service.update_entity(existing, data)
+                    write_result = await entity_service.update_entity_with_content(existing, data)
+                    entity = write_result.entity
+                    written_content = write_result.content
                     response.status_code = 200
                 else:
-                    entity = await entity_service.create_entity(data)
+                    write_result = await entity_service.create_entity_with_content(data)
+                    entity = write_result.entity
+                    written_content = write_result.content
                     if entity.external_id != entity_id:
                         entity = await entity_repository.update(
                             entity.id,
@@ -461,7 +473,7 @@ async def update_entity_by_id(
                 action="update_entity",
                 phase="search_index",
             ):
-                await search_service.index_entity(entity)
+                await search_service.index_entity(entity, content=written_content)
             with telemetry.scope(
                 "api.knowledge.update_entity.vector_sync",
                 domain="knowledge",
@@ -484,8 +496,12 @@ async def update_entity_by_id(
             domain="knowledge",
             action="update_entity",
             phase="read_content",
+            source="file" if fast else "memory",
         ):
-            content = await file_service.read_file_content(entity.file_path)
+            if fast:
+                content = await file_service.read_file_content(entity.file_path)
+            else:
+                content = written_content
         result = result.model_copy(update={"content": content})
 
         logger.info(
@@ -563,16 +579,19 @@ async def edit_entity_by_id(
                         find_text=data.find_text,
                         expected_replacements=data.expected_replacements,
                     )
+                    written_content = None
                 else:
                     identifier = entity.permalink or entity.file_path
-                    updated_entity = await entity_service.edit_entity(
+                    write_result = await entity_service.edit_entity_with_content(
                         identifier=identifier,
                         operation=data.operation,
                         content=data.content,
                         section=data.section,
                         find_text=data.find_text,
                         expected_replacements=data.expected_replacements,
                     )
+                    updated_entity = write_result.entity
+                    written_content = write_result.content
 
             if fast:
                 with telemetry.scope(
@@ -594,7 +613,7 @@ async def edit_entity_by_id(
                     action="edit_entity",
                     phase="search_index",
                 ):
-                    await search_service.index_entity(updated_entity)
+                    await search_service.index_entity(updated_entity, content=written_content)
                 with telemetry.scope(
                     "api.knowledge.edit_entity.vector_sync",
                     domain="knowledge",
@@ -617,8 +636,12 @@ async def edit_entity_by_id(
                 domain="knowledge",
                 action="edit_entity",
                 phase="read_content",
+                source="file" if fast else "memory",
             ):
-                content = await file_service.read_file_content(updated_entity.file_path)
+                if fast:
+                    content = await file_service.read_file_content(updated_entity.file_path)
+                else:
+                    content = written_content
             result = result.model_copy(update={"content": content})
 
             logger.info(

src/basic_memory/services/entity_service.py

@@ -1,6 +1,7 @@
 """Service for managing entities in the database."""
 
 from collections.abc import Callable
+from dataclasses import dataclass
 from datetime import datetime
 from pathlib import Path
 from typing import List, Optional, Sequence, Tuple, Union
@@ -50,6 +51,14 @@
 from basic_memory.utils import build_canonical_permalink
 
 
+@dataclass(frozen=True)
+class EntityWriteResult:
+    """Persisted entity plus the markdown written during this call."""
+
+    entity: EntityModel
+    content: str
+
+
 class EntityService(BaseService[EntityModel]):
     """Service for managing entities in the database."""
 
@@ -79,7 +88,7 @@ def __init__(
 
     async def detect_file_path_conflicts(
         self, file_path: str, skip_check: bool = False
-    ) -> List[Entity]:
+    ) -> List[str]:
         """Detect potential file path conflicts for a given file path.
 
         This checks for entities with similar file paths that might cause conflicts:
@@ -93,28 +102,19 @@ async def detect_file_path_conflicts(
             skip_check: If True, skip the check and return empty list (optimization for bulk operations)
 
         Returns:
-            List of entities that might conflict with the given file path
+            List of file paths that might conflict with the given file path
         """
         if skip_check:
             return []
 
         from basic_memory.utils import detect_potential_file_conflicts
 
-        conflicts = []
-
-        # Get all existing file paths
-        all_entities = await self.repository.find_all()
-        existing_paths = [entity.file_path for entity in all_entities]
+        # Load only file paths. Conflict detection is on the hot write path and
+        # does not need observations or relations.
+        existing_paths = await self.repository.get_all_file_paths()
 
         # Use the enhanced conflict detection utility
-        conflicting_paths = detect_potential_file_conflicts(file_path, existing_paths)
-
-        # Find the entities corresponding to conflicting paths
-        for entity in all_entities:
-            if entity.file_path in conflicting_paths:
-                conflicts.append(entity)
-
-        return conflicts
+        return detect_potential_file_conflicts(file_path, existing_paths)
 
     async def resolve_permalink(
         self,
@@ -143,8 +143,7 @@ async def resolve_permalink(
         )
         if conflicts:
             logger.warning(
-                f"Detected potential file path conflicts for '{file_path_str}': "
-                f"{[entity.file_path for entity in conflicts]}"
+                f"Detected potential file path conflicts for '{file_path_str}': {conflicts}"
             )
 
         # If markdown has explicit permalink, try to validate it
@@ -255,6 +254,10 @@ async def create_or_update_entity(self, schema: EntitySchema) -> Tuple[EntityMod
 
     async def create_entity(self, schema: EntitySchema) -> EntityModel:
         """Create a new entity and write to filesystem."""
+        return (await self.create_entity_with_content(schema)).entity
+
+    async def create_entity_with_content(self, schema: EntitySchema) -> EntityWriteResult:
+        """Create a new entity and return both the entity row and written markdown."""
         logger.debug(f"Creating entity: {schema.title}")
 
         # Get file path and ensure it's a Path object
@@ -328,10 +331,19 @@ async def create_entity(self, schema: EntitySchema) -> EntityModel:
             action="create",
             phase="update_checksum",
         ):
-            return await self.repository.update(entity.id, {"checksum": checksum})
+            updated = await self.repository.update(entity.id, {"checksum": checksum})
+        if not updated:  # pragma: no cover
+            raise ValueError(f"Failed to update entity checksum after create: {entity.id}")
+        return EntityWriteResult(entity=updated, content=final_content)
 
     async def update_entity(self, entity: EntityModel, schema: EntitySchema) -> EntityModel:
         """Update an entity's content and metadata."""
+        return (await self.update_entity_with_content(entity, schema)).entity
+
+    async def update_entity_with_content(
+        self, entity: EntityModel, schema: EntitySchema
+    ) -> EntityWriteResult:
+        """Update an entity and return both the entity row and written markdown."""
         logger.debug(
             f"Updating entity with permalink: {entity.permalink} content-type: {schema.content_type}"
         )
@@ -444,8 +456,10 @@ async def update_entity(self, entity: EntityModel, schema: EntitySchema) -> Enti
             phase="update_checksum",
         ):
             entity = await self.repository.update(entity.id, {"checksum": checksum})
+        if not entity:  # pragma: no cover
+            raise ValueError(f"Failed to update entity checksum after update: {file_path}")
 
-        return entity
+        return EntityWriteResult(entity=entity, content=final_content)
 
     async def fast_write_entity(
         self,
@@ -988,6 +1002,27 @@ async def edit_entity(
             EntityNotFoundError: If the entity cannot be found
             ValueError: If required parameters are missing for the operation or replacement count doesn't match expected
         """
+        return (
+            await self.edit_entity_with_content(
+                identifier=identifier,
+                operation=operation,
+                content=content,
+                section=section,
+                find_text=find_text,
+                expected_replacements=expected_replacements,
+            )
+        ).entity
+
+    async def edit_entity_with_content(
+        self,
+        identifier: str,
+        operation: str,
+        content: str,
+        section: Optional[str] = None,
+        find_text: Optional[str] = None,
+        expected_replacements: int = 1,
+    ) -> EntityWriteResult:
+        """Edit an entity and return both the entity row and written markdown."""
         logger.debug(f"Editing entity: {identifier}, operation: {operation}")
 
         with telemetry.scope(
@@ -1055,8 +1090,10 @@ async def edit_entity(
             phase="update_checksum",
         ):
             entity = await self.repository.update(entity.id, {"checksum": checksum})
+        if not entity:  # pragma: no cover
+            raise ValueError(f"Failed to update entity checksum after edit: {file_path}")
 
-        return entity
+        return EntityWriteResult(entity=entity, content=new_content)
 
     def apply_edit_operation(
         self,

tests/api/v2/test_knowledge_router.py

@@ -355,6 +355,7 @@ async def test_update_entity_by_id(
     response = await client.put(
         f"{v2_project_url}/knowledge/entities/{original_external_id}",
         json=update_data,
+        params={"fast": False},
     )
 
     assert response.status_code == 200
@@ -363,6 +364,8 @@ async def test_update_entity_by_id(
     # V2 update must return external_id field
     assert updated_entity.external_id is not None
     assert updated_entity.api_version == "v2"
+    assert updated_entity.content is not None
+    assert "Updated content via V2" in updated_entity.content
 
     # Verify file was updated
     file_path = file_service.get_entity_path(updated_entity)
@@ -532,6 +535,7 @@ async def test_edit_entity_by_id_append(
     response = await client.patch(
         f"{v2_project_url}/knowledge/entities/{original_external_id}",
         json=edit_data,
+        params={"fast": False},
     )
 
     assert response.status_code == 200
@@ -540,6 +544,8 @@ async def test_edit_entity_by_id_append(
     # V2 patch must return external_id field
     assert edited_entity.external_id is not None
     assert edited_entity.api_version == "v2"
+    assert edited_entity.content is not None
+    assert "Appended content" in edited_entity.content
 
     # Verify file has both original and appended content
     file_path = file_service.get_entity_path(edited_entity)

tests/api/v2/test_knowledge_router_telemetry.py

@@ -61,11 +61,12 @@ async def test_create_entity_emits_root_and_nested_spans(monkeypatch) -> None:
     entity = _fake_entity()
 
     class FakeEntityService:
-        async def create_entity(self, data):
-            return entity
+        async def create_entity_with_content(self, data):
+            return SimpleNamespace(entity=entity, content="telemetry content")
 
     class FakeSearchService:
-        async def index_entity(self, entity):
+        async def index_entity(self, entity, content=None):
+            assert content == "telemetry content"
             return None
 
     class FakeTaskScheduler:
@@ -74,7 +75,7 @@ def schedule(self, *args, **kwargs):
 
     class FakeFileService:
         async def read_file_content(self, path):
-            return "telemetry content"
+            raise AssertionError("non-fast create should not re-read file content")
 
     result = await knowledge_router_module.create_entity(
         project_id="project-123",
@@ -115,11 +116,12 @@ async def test_update_entity_emits_root_and_nested_spans(monkeypatch) -> None:
     entity = _fake_entity()
 
     class FakeEntityService:
-        async def update_entity(self, existing, data):
-            return entity
+        async def update_entity_with_content(self, existing, data):
+            return SimpleNamespace(entity=entity, content="updated telemetry content")
 
     class FakeSearchService:
-        async def index_entity(self, entity):
+        async def index_entity(self, entity, content=None):
+            assert content == "updated telemetry content"
             return None
 
     class FakeEntityRepository:
@@ -132,7 +134,7 @@ def schedule(self, *args, **kwargs):
 
     class FakeFileService:
         async def read_file_content(self, path):
-            return "updated telemetry content"
+            raise AssertionError("non-fast update should not re-read file content")
 
     response = Response()
     result = await knowledge_router_module.update_entity_by_id(
@@ -178,11 +180,12 @@ async def test_edit_entity_emits_root_and_nested_spans(monkeypatch) -> None:
     entity = _fake_entity()
 
     class FakeEntityService:
-        async def edit_entity(self, **kwargs):
-            return entity
+        async def edit_entity_with_content(self, **kwargs):
+            return SimpleNamespace(entity=entity, content="edited telemetry content")
 
     class FakeSearchService:
-        async def index_entity(self, entity):
+        async def index_entity(self, entity, content=None):
+            assert content == "edited telemetry content"
             return None
 
     class FakeEntityRepository:
@@ -195,7 +198,7 @@ def schedule(self, *args, **kwargs):
 
     class FakeFileService:
         async def read_file_content(self, path):
-            return "edited telemetry content"
+            raise AssertionError("non-fast edit should not re-read file content")
 
     result = await knowledge_router_module.edit_entity_by_id(
         data=EditEntityRequest(operation="append", content="edited telemetry content"),