System Services Library
The system services library offers an API to interact with system services, allowing the user to perform typical operations like querying the services, starting or stopping them, etc.
The set of classes which are included in this library can be divided into:
- A high level API which offers some abstractions on top of Systemd.
- A low level one to talk closely to Systemd units (including services and sockets).
Additionally, a widget that can be used in YaST modules (like yast2-dns-server) is included.
High Level API
The high level API is composed by these classes:
- Yast2::SystemService: represents a service (like
cups
ordbus
) from a high level point of view. Systemd concepts like units or sockets are abstracted by this class. - Yast2::CompoundService: groups a set of related services that might be handled together.
Think, for instance, about
iscsi
,iscsid
andiscsiuio
services inyast2-iscsi-client
. This class offers basically the same API than Yast2::SystemService.
Low Level API
The low level API can be more convenient in some situations and it is basically composed of a set of classes that map to Systemd concepts: Yast2::Systemd::Unit, Yast2::Systemd::Service, Yast2::Systemd::Socket and Yast2::Systemd::Target.
Service Widget
Additionally to the classes to interact with system services, this library offers a widget which
allows the user to decide how (and when) a service should be started. It is meant to be used by
modules which configure a given service (like yast2-dns-server
or yast2-iscsi-client
).
See Yast2::ServiceWidget for the widget documentation and CWM::ServiceWidget for the CWM wrapper.