FastAPI Module

fluvius.fastapi builds a standard FastAPI app, installs Fluvius error contracts and health checks, and mounts authentication, domain, query, and media capabilities.

from fluvius.fastapi import (
    configure_authentication,
    configure_domain_manager,
    configure_query_manager,
    create_app,
)

app = (
    create_app(pkginfo)
    | configure_authentication(auth_profile_provider=ProfileProvider)
    | configure_domain_manager(UserDomain)
    | configure_query_manager(UserQueryManager)
)

The factory requires a metadata module/object containing at least a version and name. Configurators receive the app and return it, so ordering is explicit.

Custom routes and auth

from fastapi import Request
from fluvius.fastapi import auth_required


@app.get("/protected")
@auth_required()
async def protected(request: Request):
    user = request.state.auth_context.user
    return {"user": user}

Framework failures use application/problem+json. Request IDs, startup wiring validation, policy validation, readiness state, and optional custom response envelopes are handled centrally.

Route base

FLUVIUS_API_BASE defaults to /api. Framework-owned auth, domain, query, docs, and transport routes honor the configured base; custom FastAPI routes remain where the application declares them.

For MCP, compose configure_mcp_server from fluvius.mcp. For realtime services, compose the configurators from fluvius.transport.