Memory 3: Service Layer

[gotsysdba]

Create a package resembling:

src/server/app/memory/
|-- adapters.py
|-- config.py
|-- registry.py
|-- schemas.py
+-- service.py

Responsibilities:

• Resolve the configured database pool and model credentials.
• Translate the repository's LiteLlmModelSpec and embedding configuration into SDK Llm and Embedder instances.
• Cache components by database, model, and configuration identity, not by user.
• Invalidate the cache after relevant configuration or credential changes.
• Close SDK components during application shutdown.
• Require a MemoryPrincipal on every scoped call.
• Always search with exact user_id matching.
• Return project-owned Pydantic DTOs rather than exposing SDK objects directly.
• Map SDK exceptions into stable API error categories.
• Never log prompts, stored content, search queries, metadata, user IDs, or thread IDs.

Recommended service methods:

• create_thread
• get_thread
• append_turn
• get_messages
• add_memory
• search_memories
• update_memory
• delete_memory
• delete_thread
• get_summary
• get_context_card

Include request or turn IDs and deterministic message IDs for retry safety. This matters for streaming reconnects and multi-replica deployments.