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App factory

create_bluefox_app() builds a fully configured FastAPI application.

Usage

from bluefox_core import BluefoxSettings, create_bluefox_app

settings = BluefoxSettings()
app = create_bluefox_app(settings)

What it does

  1. Configures logging via configure_logging(settings)
  2. Creates a DatabaseManager (no-op if DATABASE_URL is empty)
  3. Creates a Redis client (if REDIS_URL is set)
  4. Sets up the lifespan — startup verifies DB/Redis connectivity, shutdown disposes resources (wrapped in try/finally for safe cleanup)
  5. Adds middleware:
    • RequestIDMiddleware — injects X-Request-ID headers and log context
    • CORSMiddleware — permissive in development, restrictive in production
  6. Stores state — app.state.db, app.state.redis, app.state.settings
  7. Mounts the health router — /health and /readiness
  8. Mounts the demo app (if demo=True) — Todo CRUD at /demo/todos
  9. Mounts the welcome page — shown at / when no user route exists for that path

Parameters

Parameter Type Default Description
settings BluefoxSettings required Application settings
demo bool False Mount the demo Todo CRUD app

CORS behavior

Setting Development Production
allow_origins ["*"] []
allow_credentials True False
allow_methods ["*"] ["GET", "POST", "PUT", "PATCH", "DELETE"]
allow_headers ["*"] ["*"]

App state

After creation, the following are available on app.state:

Attribute Type Description
app.state.settings BluefoxSettings The settings instance
app.state.db DatabaseManager Database manager (engine may be None)
app.state.redis Redis | None Redis client, or None if not configured

Welcome page

The welcome page is served at GET / via a 404 exception handler. When you register your own GET / route, FastAPI matches it first and the welcome page is never triggered.

from fastapi import APIRouter

router = APIRouter()

@router.get("/")
async def home():
    return {"message": "My app"}

app.include_router(router)
# GET / now returns {"message": "My app"} instead of the welcome page