NCM::Component::Systemd::Service::Unit

NAME

NCM::Component::Systemd::Service::Unit is a class handling services with units

Public methods

  • new

Returns a new object, accepts the following options

  • log

A logger instance (compatible with CAF::Object).

  • unit_text

Convert unit detail hashref to human readable string.

Generates errors for missing attributes.

  • current_units

Return hash reference with current units determined via make_cache_alias.

The array references units and possible_missing are passed to make_cache_alias.

  • current_target

Return the current target.

TODO: implement this. systemctl list-units –type target lists all current targets (yes, with an s).

  • default_target

Return the default target.

Supported options:

  • force

Force is passed to the fill_cache method.

  • configured_units

configured_units parses the tree hash reference and builds up the units to be configured. It returns a hash reference with key the unit name and values the details of the unit.

Units with missing types are assumed to be TYPE_SERVICE; targets with missing type are assumed to be TYPE_TARGET.

(tree is typcially obtained with the _getTree method).

  • get_aliases

Given an arrayref of units, return a hashref with key the unit (from the list) that is an alias for another unit (not necessarily from the list); and the other unit’s name is the value.

The unit_alias cache is used for lookup.

The possible_missing arrayref is passed to the fill_cache method

Supported options

  • force

The force flag is passed to the fill_cache method

  • possible_missing

The possible_missing arrayref is passed to make_cache_alias.

  • possible_missing

Given the hashref units with key unit and value the unit’s details, return a array ref with units that are “possible missing”. Such units will not cause an error to be logged if they are not found in the cache during certain methods (e.g. make_cache_alias).

Private methods

  • is_possible_missing

Determine if unit is possible_missing (see make_cache_alias). (Returns 0 or 1).

A unit is possible_missing if

  • the unit is in state masked (i.e. unit that is not expected to be running anyway). Unit in state disabled is not “possible missing” (they can be dependency for other units).

  • init_cache

(Re)Initialise all unit caches.

Returns the caches (for unittestung mainly).

Affected caches are

  • unit_cache

  • unit_alias

  • dependency_cache

  • get_type_shortname

get_type_shortname returns the type and shortname based on the unit and optional type.

If the type is not specified, it will be derived using the supported types.

If the type can’t be determined based on the supported types, the defaulttype will be used. If in this case the defaulttype is undefined, DEFAULT_TYPE will be used and error will be logged. If the defaulttype is defined,

  • make_cache_alias

(Re)generate the unit_cache and unit_alias map based on current units and unitfiles from the systemctl_list_units and systemctl_list_unit_files methods.

Details for each unit from arrayref units are also added. If units is empty/undef, all found units and unitfiles are.

If a unit is an alias of an other unit, it is added to the alias map. Each non-alias unit is also added as it’s own alias.

Units in the possible_missing arrayref can be missing, and no error is logged if they are. For any other unit, an error is logged when neither the systemctl_list_units and systemctl_list_unit_files methods provide any information about it.

Returns the generated cache and alias map for unittesting purposes.

  • fill_cache

Fill the unit_cache and unit_alias map for the arrayref units provided.

The cache is updated via the make_cache_alias method if the unit is missing from the unit_alias map or if force is true.

Supported options

  • force

Force cache refresh.

  • possible_missing

The possible_missing arrayref is passed to make_cache_alias.

  • get_unit_show

Return the show property for unit from the unit_cache and unit_alias map.

Supported options

  • force

Force cache refresh.

  • possible_missing

If true, this unit is “possible missing” (see make_cache_alias)

  • get_wantedby

Return a hashref of all units that “want” unit (hashref is used for easy lookup; the key is the unit, the value is a boolean).

It uses the dependency_cache for reverse dependencies (missing cache entries are added).

Supported options

  • force

Force cache update.

  • ignoreself

By default, the reverse dependency list contains the unit itself too. With ignoreself true, the unit itself is not returned (but still stored in cache).

  • is_wantedby

Return if unit is wanted by target.

Any unit can be passed as target (it does not have to be a unit of type ‘target’).

It uses the get_wantedby method for the dependency lookup.

Supported options

  • force

Force cache update (passed to get_wantedby).

  • is_active

is_active returns true or false and reflects if a unit is “running” or not.

The following options are supported

  • sleeptime =item max

Units that are ‘reloading’, ‘activating’ and ‘deactivating’ are refreshed with sleep (default 1 sec) and max number of tries (default 3). Until

  • force

Force cache refresh (passed to get_unit_show).

  • get_ufstate

Return the state of the unit using the UnitFileState and the derived state from the state of the $PROPERTY_WANTEDBY units.

The returned state can be more then the usual supported states (e.g. static).

The following options are supported

  • force

Force cache refresh (passed to get_unit_show and fill_cache)

  • is_ufstate

is_ufstate returns true or false if the UnitFileState of unit matches the (simplified) state.

An error is logged and undef returned if the unit can’t be queried.

The following options are supported

  • force

Refresh the cache force (passed to get_ufstate method).

  • derived

Boolean (default true) to use derived information when UnitFileState itself is empty/undefined.

Private methods

  • _getTree

The getTree method is similar to the regular EDG::WP4::CCM::CacheManager::Element::getTree, except that it keeps the unitfile configuration as an Element instance (as required by NCM::Component::Systemd::UnitFile).

It takes as arguments a EDG::WP4::CCM::CacheManager::Configuration instance $config and a $path to the root of the whole unit tree.