Fix stale database connections in async MCP handlers #4
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Same DEFAULT_EXEMPTIONS as secrets_filter.py - prevents redacting common non-sensitive values like database names (pickipedia, mediawiki, etc.)
When Django ORM queries are wrapped with sync_to_async in a long-running async process, database connections can become stale. This manifests as "connection already closed" errors when calling MCP tools. Solution: Add a with_fresh_connection wrapper that calls close_old_connections() before and after each database operation, ensuring a fresh connection for every MCP tool call.
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Summary
with_fresh_connectionwrapper that ensures fresh DB connections for each tool callRoot Cause
When Django ORM queries are wrapped with
sync_to_asyncin a long-running async process (like the MCP server), database connections can become stale between tool invocations. PostgreSQL connections time out, but Django's connection pool doesn't automatically detect and refresh them.Solution
Call
django.db.close_old_connections()before and after each database operation, forcing Django to establish a fresh connection.Test plan
bootstrap_memoryMCP tool