apply service

The earlier versions of ram framework (prior to release 0.2.0) only allow querying, modifying and storing configurations to the corresponding configuration files. However, it is usually required to restart the corresponding services to apply changes, so a user has to remember what services to restart or what commands to run.

The 0.2.0 version of ram framework allows unit developers to create apply actions for their units. The apply action is a regular shell script that takes care of services related to settings managed by unit. To avoid excessive service restarts, unit developer has to add checks if settings in effect are the same as settings in configuration files.

In the earlier version of ram framework (prior to release 0.2.0) the apply action is used to copy configuration from unit storage to the actual system configs. In the current version, role of the apply action is redefined for applying changes to a running system and the store action is used for updating system configs. As a result, a typical ram unit session looks as follows:

# # query from system configs and put values to unit's storage
# ram query ifconfig

# # run actual end user interaction using front end
# ram input ifconfig

# # get values from unit's storage and store to system configs
# ram store ifconfig

# # meta-action setup could be used to run query/input/store in sequence
# ram setup ifconfig

# # apply system configs in effect
# ram apply ifconfig

It is not always required to apply settings right after they have been edited. By default, The apply action has to be invoked separately and not run by the setup meta-action. It is possible to change this behavior using the apply option managed by the``tweak`` command. If this option is set, the apply action is invoked after each successful setup action:

# ram tweak apply on

# # no need for separate apply invocation now
# ram setup ifconfig

The option is persistent and system-wide. Once set, it applies to every invocation of the setup action on the machine.