fleet-memory/hindsight-api/hindsight_api/extensions/context.py
Chris Bartholomew 6fe93140a7
Fix embedding dimension for tenant schemas (#135)
Call ensure_embedding_dimension after running migrations for tenant
schemas. This ensures the embedding column dimension matches the
model's dimension, which may differ from the default 384 dimensions
used in the initial migration.

Without this fix, using embedding providers with different dimensions
(e.g., Cohere's embed-english-v3.0 with 1024 dims) would fail with
"expected 384 dimensions, not 1024" errors on tenant schemas.
2026-01-08 22:48:25 +01:00

126 lines
4.4 KiB
Python

"""Extension context providing a controlled API for extensions to interact with the system."""
from abc import ABC, abstractmethod
from typing import TYPE_CHECKING
if TYPE_CHECKING:
from hindsight_api.engine.interface import MemoryEngineInterface
class ExtensionContext(ABC):
"""
Abstract context providing a controlled API for extensions.
Extensions receive this context instead of direct access to internal
components like MemoryEngine or database connections. This provides:
- A stable API that won't break when internals change
- Security by limiting what extensions can access
- Clear documentation of what extensions can do
Built-in implementation:
hindsight_api.extensions.builtin.context.DefaultExtensionContext
Example usage in an extension:
class MyTenantExtension(TenantExtension):
async def on_startup(self) -> None:
# Run migrations for a new tenant schema
await self.context.run_migration("tenant_acme")
class MyHttpExtension(HttpExtension):
def get_router(self, memory):
# Use memory engine for custom endpoints
engine = self.context.get_memory_engine()
...
"""
@abstractmethod
async def run_migration(self, schema: str) -> None:
"""
Run database migrations for a specific schema.
This creates the schema if it doesn't exist and runs all pending
migrations. Uses advisory locks to coordinate between distributed workers.
Args:
schema: PostgreSQL schema name (e.g., "tenant_acme").
The schema will be created if it doesn't exist.
Raises:
RuntimeError: If migrations fail to complete.
Example:
# Provision a new tenant schema
await context.run_migration("tenant_acme")
"""
...
@abstractmethod
def get_memory_engine(self) -> "MemoryEngineInterface":
"""
Get the memory engine interface.
Returns the MemoryEngineInterface for performing memory operations
like retain, recall, reflect, and entity/document management.
Returns:
MemoryEngineInterface instance.
Example:
engine = context.get_memory_engine()
result = await engine.recall_async(bank_id, query)
"""
...
class DefaultExtensionContext(ExtensionContext):
"""
Default implementation of ExtensionContext.
Uses the system's database URL and migration infrastructure.
"""
def __init__(
self,
database_url: str,
memory_engine: "MemoryEngineInterface | None" = None,
):
"""
Initialize the context.
Args:
database_url: SQLAlchemy database URL for migrations.
memory_engine: Optional MemoryEngine instance for memory operations.
"""
self._database_url = database_url
self._memory_engine = memory_engine
async def run_migration(self, schema: str) -> None:
"""Run migrations for a specific schema."""
from hindsight_api.migrations import ensure_embedding_dimension, run_migrations
# Prefer getting URL from memory engine (handles pg0 case where URL is set after init)
db_url = self._database_url
if self._memory_engine is not None:
engine_url = getattr(self._memory_engine, "db_url", None)
if engine_url:
db_url = engine_url
run_migrations(db_url, schema=schema)
# Ensure embedding column dimension matches the model's dimension
# This is needed because migrations create columns with default dimension
if self._memory_engine is not None:
embeddings = getattr(self._memory_engine, "embeddings", None)
if embeddings is not None:
dimension = getattr(embeddings, "dimension", None)
if dimension is not None:
ensure_embedding_dimension(db_url, dimension, schema=schema)
def get_memory_engine(self) -> "MemoryEngineInterface":
"""Get the memory engine interface."""
if self._memory_engine is None:
raise RuntimeError(
"Memory engine not configured in ExtensionContext. "
"Ensure the context was created with a memory_engine parameter."
)
return self._memory_engine