oservices

Services and components management

Definitions

• Package: python package
• Service: system that provides a public api via a port. Can contain multiple processes.
• Component: element of a service. Only one long-running process by component. In certain cases, this process may create and kill other processes. These must be strongly dependant on the main process, or else create a different component.
• System: multi-services working together
• Neutral: does not require a setup to be imported
• Configuration: in memory placeholder for configuration variables. May be dumped and loaded to file. Can be attached to a package, a service or a component.
• Settings: placeholder for a small set of variables, depending on where is installed a component, that will be loaded on thread awakening and propagated to all concerned configuration objects.
• Administrator: system that manages administration for a pool of components. These components may be attached to different services.

Workflow

• Configure a configuration: set all conf variables
• Configure a service: configure all configurations of service
• Setup: setup django and logging
• Initialize: initialize files
• Build: generate configuration files

API management

Package

• A package exposes it's public objects, functions and classes through the init file.
• A package has a conf.py file if needed. It is not necessarily stored in admin package.

Service

• A service is a package containing a service.md file. This file explains where the different components are, especially the public api component.
• A service contains components, and may contain neutral files (like package files).
• All service configuration related files must live in the admin package, with correctly named files.

Component

• A component is a package containing a component.py file.
• A component only exposes it's CONF, CONFIGURATION, Client and Mock

Signals

Exit signals are only managed if components are started in processes. If run in main process, the caller needs to manage.