async def METHOD_NAME(request: web.Request):
    """Readiness probe: "Check if the container is ready to receive traffic"
    When the target service is unhealthy, no traffic should be sent to it. Service discovery
    services and load balancers (e.g. traefik) typically cut traffic from targets
    in one way or another.
    SEE doc in healthcheck.py
    """
    healthcheck: HealthCheck = request.app[HealthCheck.__name__]
    health_report = healthcheck.get_app_info(request.app)
    # NOTE: do NOT run healthcheck here, just return info fast.
    return envelope_json_response(health_report)