backend-logging

name	backend-logging
description	Wide event logging system reference. Covers WideEventMiddleware, canonical log lines, structured context helpers (log_action, log_entity, log_custom, log_user), and sensitive data sanitization. Use when adding logging to new features or debugging request flow.

Backend Logging System

Overview

The backend uses a wide event / canonical log lines pattern. Each HTTP request produces exactly one structured log entry at completion, enriched with context accumulated during handling.

Location: app/core/logging/

Architecture

Request → WideEventMiddleware → RequestContextMiddleware → Route Handler
                                                              ↓
                                                     log_action("create")
                                                     log_entity("item", id)
                                                     log_custom(key=value)
                                                              ↓
WideEventMiddleware ← emits one log line with all accumulated context

Quick Usage in Handlers

Import helpers from app/core/logging:

from app.core.logging import log_action, log_entity, log_entities, log_custom

@router.post("")
async def create_item(item: ItemCreate, service: ItemService = Depends(get_item_service)):
    log_action("create")                    # Set the business action
    result = await service.create(item)
    log_entity(, result.)           
     result


  ():
    log_action()
    results =  service.get_all()
    log_entities(, [r.  r  results])  
     results