What, When and Where of subscription-manager

Many different apps can load and run subscription-manager code, and they are not particularly consistent in how they do it.

Some parts of subscription-manager code only need to happen once per process (log and config setup, for example). Other aspects can happen more often, but should be kept to a minimum (loading client side certificates, reading/write caches, etc.).

/usr/sbin/subscription-manager

1. sets up i18n (i18n.configure_i18n())
2. sets up logging (logutil.init_logger())
3. sets up dep injection (injectioninit.init_dep_injection())
4. import managercli
5. runs managercli.ManagerCLI().main()

ManagerCLI() creates an instance of each of the managercli.*Command classes.

The ManagerCLI().main() runs the Command.main() of the command. The main() parses all the args, sets up connections to Candlepin (UEP, etc.) if needed, and runs the Command._do_command()

All the CliCommand() subclasses are init()‘ed, but only one will have its .main() and its _do_command() triggered.