cfe_internal/update/lib.cf

Table of Contents

agent bundles

u_systemd_services

Prototype: u_systemd_services(service, state)

Description: Manage standard systemd services

Arguments:

  • service: The name of the service
  • state: The desired state the service should be in.

Implementation:

bundle agent u_systemd_services(service,state)
{
  vars:

    # We explicitly guard for systemd to avoid unnecessary agent time in
    # pre-eval

    systemd::
      "systemctl" string => "/bin/systemctl";
      "call_systemctl" string => "$(systemctl) --no-ask-password --global --system";
      "systemd_properties" string => "-pLoadState,CanStop,UnitFileState,ActiveState,LoadState,CanStart,CanReload";
      "systemd_service_info" slist => string_split(execresult("$(call_systemctl) $(systemd_properties) show $(service)", "noshell"), "\n", "10");

  classes:

    systemd::

      # define a class named after the desired state
      "$(state)" expression => "any";
      "non_disabling" or => { "start", "stop", "restart", "reload" };

# A collection of classes to determine the capabilities of a given systemd
# service, then start, stop, etc. the service. Also supports a custom action
# for anything not supported

      "service_enabled" expression => reglist(@(systemd_service_info), "UnitFileState=enabled");
      "service_active"  expression => reglist(@(systemd_service_info), "ActiveState=active");
      "service_loaded"  expression => reglist(@(systemd_service_info), "LoadState=loaded");
      "service_notfound" expression => reglist(@(systemd_service_info), "LoadState=not-found");

      "can_stop_service"   expression => reglist(@(systemd_service_info), "CanStop=yes");
      "can_start_service"  expression => reglist(@(systemd_service_info), "CanStart=yes");
      "can_reload_service" expression => reglist(@(systemd_service_info), "CanReload=yes");

      "request_start"   expression => strcmp("start", "$(state)");
      "request_stop"    expression => strcmp("stop", "$(state)");
      "request_reload"  expression => strcmp("reload", "$(state)");
      "request_restart" expression => strcmp("restart", "$(state)");

      "action_custom"  expression => "!(request_start|request_stop|request_reload|request_restart)";
      "action_start"   expression => "request_start.!service_active.can_start_service";
      "action_stop"    expression => "request_stop.service_active.can_stop_service";
      "action_reload"  expression => "request_reload.service_active.can_reload_service";
      "action_restart"         or => {
                                      "request_restart",

                                      # Possibly undesirable... if a reload is
                                      # requested, and the service "can't" be
                                      # reloaded, then we restart it instead.
                                      "request_reload.!can_reload_service.service_active",
                                     };

      # Starting a service implicitly enables it
      "action_enable"  expression => "request_start.!service_enabled";

      # Respectively, stopping it implicitly disables it
      "action_disable" expression => "request_stop.service_enabled";

  commands:
    systemd.service_loaded:: # note this class is defined in `inventory/linux.cf`
      # conveniently, systemd states map to `services` states, except
      # for `enable`

      "$(call_systemctl) -q start $(service)"   ifvarclass => "action_start";
      "$(call_systemctl) -q stop $(service)"    ifvarclass => "action_stop";
      "$(call_systemctl) -q reload $(service)"  ifvarclass => "action_reload";
      "$(call_systemctl) -q restart $(service)" ifvarclass => "action_restart";
      "$(call_systemctl) -q enable $(service)"  ifvarclass => "action_enable";
      "$(call_systemctl) -q disable $(service)" ifvarclass => "action_disable";

      # Custom action for any of the non-standard systemd actions such a
      # status, try-restart, isolate, et al.
      "$(call_systemctl) $(state) $(service)" ifvarclass => "action_custom";

  reports:
    DEBUG|DEBUG_u_systemd_service::
      "DEBUG $(this.bundle): using systemd layer to $(state) $(service)";

      "DEBUG $(this.bundle): Service $(service) unit file is not loaded; doing nothing"
        ifvarclass => "systemd.!service_loaded";

      "DEBUG $(this.bundle): Could not find service: $(service)"
        ifvarclass => "systemd.service_notfound";
}

classes bodies

u_results

Prototype: u_results(scope, class_prefix)

Description: Define classes prefixed with class_prefix and suffixed with appropriate outcomes: _kept, _repaired, _not_kept, _error, _failed, _denied, _timeout, _reached

Arguments:

  • scope: The scope in which the class should be defined (bundle or namespace)
  • class_prefix: The prefix for the classes defined

This body can be applied to any promise and sets global (namespace) or local (bundle) classes based on its outcome. For instance, with class_prefix set to abc:

  • if the promise is to change a file's owner to nick and the file was already owned by nick, the classes abc_reached and abc_kept will be set.

  • if the promise is to change a file's owner to nick and the file was owned by adam and the change succeeded, the classes abc_reached and abc_repaired will be set.

This body is a simpler, more consistent version of the body scoped_classes_generic, which see. The key difference is that fewer classes are defined, and only for outcomes that we can know. For example this body does not define "OK/not OK" outcome classes, since a promise can be both kept and failed at the same time.

It's important to understand that promises may do multiple things, so a promise is not simply "OK" or "not OK." The best way to understand what will happen when your specific promises get this body is to test it in all the possible combinations.

Suffix Notes:

  • _reached indicates the promise was tried. Any outcome will result in a class with this suffix being defined.

  • _kept indicates some aspect of the promise was kept

  • _repaired indicates some aspect of the promise was repaired

  • _not_kept indicates some aspect of the promise was not kept. error, failed, denied and timeout outcomes will result in a class with this suffix being defined

  • _error indicates the promise repair encountered an error

  • _failed indicates the promise failed

  • _denied indicates the promise repair was denied

  • _timeout indicates the promise timed out

Example:

bundle agent example
{
  commands:
    "/bin/true"
      classes => results("bundle", "my_class_prefix");

  reports:
    my_class_prefix_kept::
      "My promise was kept";

    my_class_prefix_repaired::
      "My promise was repaired";
}

See also: scope, scoped_classes_generic, classes_generic

Implementation:

body classes u_results(scope, class_prefix)
{
  scope => "$(scope)";

  promise_kept => { "$(class_prefix)_reached",
                    "$(class_prefix)_kept" };

  promise_repaired => { "$(class_prefix)_reached",
                        "$(class_prefix)_repaired" };

  repair_failed => { "$(class_prefix)_reached",
                     "$(class_prefix)_error",
                     "$(class_prefix)_not_kept",
                     "$(class_prefix)_failed" };

  repair_denied => { "$(class_prefix)_reached",
                     "$(class_prefix)_error",
                     "$(class_prefix)_not_kept",
                     "$(class_prefix)_denied" };

  repair_timeout => { "$(class_prefix)_reached",
                      "$(class_prefix)_error",
                      "$(class_prefix)_not_kept",
                      "$(class_prefix)_timeout" };
}

depth_search bodies

u_cfe_internal_recurse

Prototype: u_cfe_internal_recurse(d)

Description: Search for files recursively to a depth of d across file system boundaries

Arguments:

  • d: Number of levels deep to traverse

Implementation:

body depth_search u_cfe_internal_recurse(d)
{
      depth => "$(d)";
      xdev => "true";
}

classes bodies

u_kept_successful_command_results

Prototype: u_kept_successful_command_results(scope, class_prefix)

Description: Set command to "kept" instead of "repaired" if it returns 0 and define classes suffixed with the appropriate outcomes.

Arguments:

  • scope: The scope in which the class should be defined (bundle or namespace)
  • class_prefix: The prefix for the classes defined

See also: scope, scoped_classes_generic, classes_generic, results TODO After cfengine_3_10 is no longer supported inherit from u_results and add in the return code differences.

Implementation:

body classes u_kept_successful_command_results(scope, class_prefix)
{
  kept_returncodes => { "0" };
  failed_returncodes => { "1" };

  scope => "$(scope)";

  promise_kept => { "$(class_prefix)_reached",
                    "$(class_prefix)_kept" };

  promise_repaired => { "$(class_prefix)_reached",
                        "$(class_prefix)_repaired" };

  repair_failed => { "$(class_prefix)_reached",
                     "$(class_prefix)_error",
                     "$(class_prefix)_not_kept",
                     "$(class_prefix)_failed" };

  repair_denied => { "$(class_prefix)_reached",
                     "$(class_prefix)_error",
                     "$(class_prefix)_not_kept",
                     "$(class_prefix)_denied" };

  repair_timeout => { "$(class_prefix)_reached",
                      "$(class_prefix)_error",
                      "$(class_prefix)_not_kept",
                      "$(class_prefix)_timeout" };
}

service_method bodies

u_systemd_services

Prototype: u_systemd_services

Description: Define service method for systemd

Implementation:

body service_method u_systemd_services
{
      service_autostart_policy => "none";
      service_dependence_chain => "ignore";
      service_type => "generic";
      service_args => "";
}

perms bodies

u_mog

Prototype: u_mog(mode, user, group)

Description: Set the file's mode, owner and group

Arguments:

  • mode: The new mode
  • user: The username of the new owner
  • group: The group name

Implementation:

body perms u_mog(mode,user,group)
{
      owners => { "$(user)" };
      groups => { "$(group)" };
      mode   => "$(mode)";
}