mentat.daemon.component.inspector module

Daemon component providing simple yet powerfull message processing tools based on performing conditional actions according to list of filtering rules.

It is dependent on services of following modules:

• pynspect.filters

  Filtering rule library.

• pynspect.compilers

  Filtering rule compilation library.

The implementation is based on pyzenkit.zendaemon.ZenDaemonComponent.

Setup configuration

This daemon component requires that following configurations are provided by external daemon:

inspection_rules

List of inspection rules. See section Inspection rules below for more information about available actions.

fallback_actions

List of fallback actions. See section Inspection actions below for more information about available actions.

Inspection rules

Inspection rules define what actions should be performed with what messages. Every inspection rule may have following attributes:

rule

Filtering rule compatible with pynspect.filters library. All messages will be compared to this rule and actions will be performed with those that match.

(string, mandatory)

name

Optional name for the rule to be used in logs and other user output. This should be something brief and meaningfull to uniquelly identify the rule. When not set this defaults to rule attribute.

(string, optional)

description

Optional user description of the meaning of the rule. When not set defaults to ???.

(string, optional)

final

Boolean flag indicating the rule is final and all subsequent rules should not be considered. When not set defaults to False.

(boolean, optional)

enabled

Boolean flag indicating the rule is enabled or disabled. When not set defaults to True.

(boolean, optional)

actions

List of inspection action to be performed upon filter match. See section Inspection actions for more details.

Inspection actions

Every action has following common attributes:

action

Type of the action. See below for list of all currently available actions.

(string, mandatory)

name

Optional name for the action to be used in logs and other user output. This should be something brief and meaningfull to uniquelly identify the action. When not set this defaults to action attribute.

(string, optional)

description

Optional user description of the meaning of the action. When not set defaults to ???.

(string, optional)

enabled

Boolean flag indicating the action is enabled or disabled. When not set defaults to True.

(boolean, optional)

args

Dictionary of additional arguments for the action. The appropriate arguments are specific for particular action. See below for more information for each action.

(dict, optional)

There are following inspection actions, that can be performed with matching messages or as fallback action:

tag

Tag the corresponding message at given JPath with given value. The tag value may be only constant value.

Arguments:

• path - JPath to be set (string, mandatory)

• value - value to be set (any, mandatory)

• overwrite - flag indicating whether existing value should be overwritten, or not, defaults to True (boolean, optional)

• unique - flag indicating whether value should be unique, or not, defaults to False (boolean, optional)

set

Set the corresponding message at given JPath with result of given expression. The expression must be compatible with JPath module.

Arguments:

• path - JPath to be set (string, mandatory)

• expression - JPath compatible expression to be set (string, mandatory)

• overwrite - flag indicating whether existing value should be overwritten, or not, defaults to True (boolean, optional)

• unique - flag indicating whether value should be unique, or not, defaults to False (boolean, optional)

unset

Unset (delete) the node at given JPath within the message.

Arguments:

• path - JPath to be deleted (string, mandatory)

report

Report the corresponding message via email.

Arguments:

• to - recipient email address (string, mandatory)

• from - sender email address (string, mandatory)

• subject - email report subject (string, mandatory)

• report_type - email report type, will be inserted into X-Cesnet-Report-Type email header (string, mandatory)

Todo

Finish usage of default arguments and then update this documentation. Currently every argument is mandatory, which makes users repeat themselves.

drop

Drop the corresponding message from processing (filter out).

This action currently does not have any arguments.

dispatch

Dispatch (move) the corresponding message into another queue directory.

Arguments:

• queue_tgt - path to target queue (string, mandatory)

duplicate

Duplicate (copy) the corresponding message into another queue directory.

Arguments:

• queue_tgt - path to target queue (string, mandatory)

log

Log the corresponding message into daemon module log.

Arguments:

• label - log message label, defaults to Inspection rule matched (string, optional)

class mentat.daemon.component.inspector.InspectorDaemonComponent(**kwargs)

Bases: pyzenkit.zendaemon.ZenDaemonComponent

ZenDaemonComponent encapsulating pynspect library and providing.

EVENT_LOG_STATISTICS = 'log_statistics'

EVENT_MSG_PROCESS = 'message_process'

STATS_CNT_DISPATCHED = 'cnt_dispatched'

STATS_CNT_DROPPED = 'cnt_dropped'

STATS_CNT_DUPLICATED = 'cnt_duplicated'

STATS_CNT_ERRORS = 'cnt_errors'

STATS_CNT_FALLBACKS = 'cnt_fallbacks'

STATS_CNT_LOGGED = 'cnt_logged'

STATS_CNT_REPORTED = 'cnt_reported'

STATS_CNT_SET = 'cnt_set'

STATS_CNT_TAGGED = 'cnt_tagged'

STATS_CNT_UNSET = 'cnt_unset'

STATS_COUNTERS = 'counters'

cbk_event_log_statistics(daemon, args)

Periodical processing statistics logging.

cbk_event_message_process(daemon, args)

Perform inspection of given message.

get_events()

Get the list of event names and their appropriate callback handlers.

rule_action_dispatch(daemon, mid, iid, message, action, rule=None)

Dispatch given message into given target queue.

rule_action_drop(daemon, mid, iid, message, action, rule=None)

Drop given messsage from processing.

rule_action_duplicate(daemon, mid, iid, message, action, rule=None)

Duplicate given message into given target queue.

rule_action_log(daemon, mid, iid, message, action, rule=None)

Log matching message with warning severity.

rule_action_report(daemon, mid, iid, message, action, rule=None)

Report given message according given arguments.

rule_action_set(daemon, mid, iid, message, action, rule=None)

Set given message key according given arguments.

rule_action_tag(daemon, mid, iid, message, action, rule=None)

Tag given message according given arguments.

rule_action_unset(daemon, mid, iid, message, action, rule=None)

Unset (delete) the node at given JPath within the message.

setup(daemon)

Perform component setup.