Log::Report::Dispatcher(3pm) User Contributed Perl Documentation Log::Report::Dispatcher(3pm)
NAME
Log::Report::Dispatcher - manage dispatching
INHERITANCE
Log::Report::Dispatcher is extended by
Log::Report::Dispatcher::Callback
Log::Report::Dispatcher::File
Log::Report::Dispatcher::Log4perl
Log::Report::Dispatcher::LogDispatch
Log::Report::Dispatcher::Perl
Log::Report::Dispatcher::Syslog
Log::Report::Dispatcher::Try
SYNOPSIS
use Log::Report;
# The following will be created for you automatically
dispatcher 'PERL', 'default', accept => 'NOTICE-';
dispatcher close => 'default'; # after deamonize
dispatcher 'FILE', 'log'
, mode => 'DEBUG', to => '/var/log/mydir/myfile';
# Full package name is used, same as 'FILE'
dispatcher Log::Report::Dispatch::File => 'stderr'
, to => *STDERR, accept => 'NOTICE-';
# Within a "try" block, there is only one dispatcher
dispatcher TRY => 'try';
DESCRIPTION
This base-class handles the creation of dispatchers, plus the common filtering rules.
See the "DETAILS" section, below.
METHODS
Constructors
$obj->close
Terminate the dispatcher activities. The dispatcher gets disabled, to avoid the case that it is accidentally used. Returns "undef"
(false) if the dispatcher was already closed.
Log::Report::Dispatcher->new(TYPE, NAME, OPTIONS)
Create a dispatcher. The TYPE of back-end to start is required, and listed in the "DESCRIPTION" part of this manual-page. For various
external back-ends, special wrappers are created.
The NAME must be uniquely identifying this dispatcher. When a second dispatcher is created (via Log::Report::dispatcher()) with the
name of an existing dispatcher, the existing one will get replaced.
All OPTIONS which are not consumed by this base constructor are passed to the wrapped back-end. Some of them will check whether all
OPTIONS are understood, other ignore unknown OPTIONS.
-Option --Default
accept depend on mode
charset <undef>
format_reason 'LOWERCASE'
locale <system locale>
mode 'NORMAL'
accept => REASONS
See Log::Report::Util::expand_reasons() for possible values. If the initial mode for this dispatcher does not need verbose or debug
information, then those levels will not be accepted.
When the mode equals "NORMAL" (the default) then "accept"'s default is "NOTICE-". In case of "VERBOSE" it will be "INFO-", "ASSERT"
results in "ASSERT-", and "DEBUG" in "ALL".
charset => CHARSET
Convert the messages in the specified character-set (codeset). By default, no conversion will take place, because the right choice
cannot be determined automatically.
format_reason => 'UPPERCASE'|'LOWERCASE'|'UCFIRST'|'IGNORE'|CODE
How to show the reason text which is printed before the message. When a CODE is specified, it will be called with a translated text
and the returned text is used.
locale => LOCALE
Overrules the global setting. Can be overruled by Log::Report::report(locale).
mode => 'NORMAL'|'VERBOSE'|'ASSERT'|'DEBUG'|0..3
Possible values are "NORMAL" (or 0 or "undef"), which will not show "INFO" or debug messages, "VERBOSE" (1; shows "INFO" not debug),
"ASSERT" (2; only ignores "TRACE" messages), or "DEBUG" (3) which shows everything. See section "Run modes" in Log::Report.
You are advised to use the symbolic mode names when the mode is changed within your program: the numerical values are available for
smooth Getopt::Long integration.
Accessors
$obj->isDisabled
$obj->mode
Returns the mode in use for the dispatcher as number. See new(mode) and "Run modes" in Log::Report.
$obj->name
Returns the unique name of this dispatcher.
$obj->needs
Returns the list with all REASONS which are needed to fulfill this dispatcher's needs. When disabled, the list is empty, but not
forgotten.
$obj->type
The dispatcher TYPE, which is usually the same as the class of this object, but not in case of wrappers like for Log::Dispatch.
Logging
$obj->collectLocation
Log::Report::Dispatcher->collectLocation
Collect the information to be displayed as line where the error occurred. Probably, this needs improvement, where carp and die show
different lines.
$obj->collectStack([MAXDEPTH])
Log::Report::Dispatcher->collectStack([MAXDEPTH])
Returns an ARRAY of ARRAYs with text, filename, line-number.
$obj->log(HASH-of-OPTIONS, REASON, MESSAGE)
This method is called by Log::Report::report() and should not be called directly. Internally, it will call translate(), which does
most of the work.
$obj->stackTraceLine(OPTIONS)
Log::Report::Dispatcher->stackTraceLine(OPTIONS)
-Option --Default
abstract 1
call <required>
filename <required>
linenr <required>
max_line undef
max_params 8
package <required>
params <required>
abstract => INTEGER
The higher the abstraction value, the less details are given about the caller. The minimum abstraction is specified, and then
increased internally to make the line fit within the "max_line" margin.
call => STRING
filename => STRING
linenr => INTEGER
max_line => INTEGER
max_params => INTEGER
package => CLASS
params => ARRAY
$obj->translate(HASH-of-OPTIONS, REASON, MESSAGE)
See "Processing the message", which describes the actions taken by this method. A string is returned, which ends on a new-line, and
may be multi-line (in case a stack trace is produced).
DETAILS
Available back-ends
When a dispatcher is created (via new() or Log::Report::dispatcher()), you must specify the TYPE of the dispatcher. This can either be a
class name, which extends a Log::Report::Dispatcher, or a pre-defined abbreviation of a class name. Implemented are:
Log::Report::Dispatcher::Perl (abbreviation 'PERL')
Use Perl's own "print()", "warn()" and "die()" to ventilate reports. This is the default dispatcher.
Log::Report::Dispatcher::File (abbreviation 'FILE')
Logs the message into a file, which can either be opened by the class or be opened before the dispatcher is created.
Log::Report::Dispatcher::Syslog (abbreviation 'SYSLOG')
Send messages into the system's syslog infrastructure, using Sys::Syslog.
"Log::Dispatch::*"
All of the Log::Dispatch::Output extensions can be used directly. The Log::Report::Dispatcher::LogDispatch will wrap around that back-
end.
"Log::Log4perl"
Use the Log::Log4perl main object to write to dispatchers. This infrastructure uses a configuration file.
Log::Report::Dispatcher::Try (abbreviation 'TRY')
Used by Log::Report::try(), it will translate reports into exceptions.
Processing the message
Addition information
The modules which use "Log::Report" will only specify the base of the message string. The base dispatcher and the back-ends will extend
this message with additional information:
. the reason
. the filename/line-number where the problem appeared
. the filename/line-number where it problem was reported
. the error text in $!
. a stack-trace
. a trailing new-line
When the message is a translatable object (Log::Report::Message, for instance created with Log::Report::__()), then the added components
will get translated as well. Otherwise, all will be in English.
Exactly what will be added depends on the actual mode of the dispatcher (change it with mode(), initiate it with new(mode)).
mode mode mode mode
REASON SOURCE TE! NORM VERB ASSE DEBUG
trace program ... S
assert program ... SL SL
info program T.. S S S
notice program T.. S S S S
mistake user T.. S S S SL
warning program T.. S S SL SL
error user TE. S S SL SC
fault system TE! S S SL SC
alert system T.! S S SC SC
failure system TE! S S SC SC
panic program .E. SC SC SC SC
T - usually translated
E - exception (execution interrupted)
! - will include $! text
L - include filename and linenumber
S - show/print when accepted
C - stack trace (like Carp::confess())
Filters
With a filter, you can block or modify specific messages before translation. There may be a wish to change the REASON of a report or its
content. It is not possible to avoid the exit which is related to the original message, because a module's flow depends on it to happen.
When there are filters defined, they will be called in order of definition. For each of the dispatchers which are called for a certain
REASON (which "accept" that REASON), it is checked whether its name is listed for the filter (when no names where specified, then the
filter is applied to all dispatchers).
When selected, the filter's CODE reference is called with four arguments: the dispatcher object (a Log::Report::Dispatcher), the HASH-of-
OPTIONS passed as optional first argument to Log::Report::report(), the REASON, and the MESSAGE. Returned is the new REASON and MESSAGE.
When the returned REASON is "undef", then the message will be ignored for that dispatcher.
Be warned about processing the MESSAGE: it is a Log::Report::Message object which may have a "prepend" string and "append" string or
object. When the call to Log::Report::report() contained multiple comma-separated components, these will already have been joined together
using concatenation (see Log::Report::Message::concat().
SEE ALSO
This module is part of Log-Report distribution version 0.94, built on August 23, 2011. Website: http://perl.overmeer.net/log-report/
LICENSE
Copyrights 2007-2011 by Mark Overmeer. For other contributors see ChangeLog.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See
http://www.perl.com/perl/misc/Artistic.html
perl v5.14.2 2011-08-23 Log::Report::Dispatcher(3pm)