###########################################
package Log::Log4perl::DateFormat;
###########################################
use warnings;
use strict;
use Carp qw( croak );
our $GMTIME = 0;
my @MONTH_NAMES = qw(
January February March April May June July
August September October November December);
my @WEEK_DAYS = qw(
Sunday Monday Tuesday Wednesday Thursday Friday Saturday);
###########################################
sub new {
###########################################
my($class, $format) = @_;
my $self = {
stack => [],
fmt => undef,
};
bless $self, $class;
# Predefined formats
if($format eq "ABSOLUTE") {
$format = "HH:mm:ss,SSS";
} elsif($format eq "DATE") {
$format = "dd MMM yyyy HH:mm:ss,SSS";
} elsif($format eq "ISO8601") {
$format = "yyyy-MM-dd HH:mm:ss,SSS";
} elsif($format eq "APACHE") {
$format = "[EEE MMM dd HH:mm:ss yyyy]";
}
if($format) {
$self->prepare($format);
}
return $self;
}
###########################################
sub prepare {
###########################################
my($self, $format) = @_;
# the actual DateTime spec allows for literal text delimited by
# single quotes; a single quote can be embedded in the literal
# text by using two single quotes.
#
# my strategy here is to split the format into active and literal
# "chunks"; active chunks are prepared using $self->rep() as
# before, while literal chunks get transformed to accommodate
# single quotes and to protect percent signs.
#
# motivation: the "recommended" ISO-8601 date spec for a time in
# UTC is actually:
#
# YYYY-mm-dd'T'hh:mm:ss.SSS'Z'
my $fmt = "";
foreach my $chunk ( split /('(?:''|[^'])*')/, $format ) {
if ( $chunk =~ /\A'(.*)'\z/ ) {
# literal text
my $literal = $1;
$literal =~ s/''/'/g;
$literal =~ s/\%/\%\%/g;
$fmt .= $literal;
} elsif ( $chunk =~ /'/ ) {
# single quotes should always be in a literal
croak "bad date format \"$format\": " .
"unmatched single quote in chunk \"$chunk\"";
} else {
# handle active chunks just like before
$chunk =~ s/(([GyMdhHmsSEeDFwWakKzZ])\2*)/$self->rep($1)/ge;
$fmt .= $chunk;
}
}
return $self->{fmt} = $fmt;
}
###########################################
sub rep {
###########################################
my ($self, $string) = @_;
my $first = substr $string, 0, 1;
my $len = length $string;
my $time=time();
my @g = gmtime($time);
my @t = localtime($time);
my $z = $t[1]-$g[1]+($t[2]-$g[2])*60+($t[7]-$g[7])*1440+
($t[5]-$g[5])*(525600+(abs($t[7]-$g[7])>364)*1440);
my $offset = sprintf("%+.2d%.2d", $z/60, "00");
#my ($s,$mi,$h,$d,$mo,$y,$wd,$yd,$dst) = localtime($time);
# Here's how this works:
# Detect what kind of parameter we're dealing with and determine
# what type of sprintf-placeholder to return (%d, %02d, %s or whatever).
# Then, we're setting up an array, specific to the current format,
# that can be used later on to compute the components of the placeholders
# one by one when we get the components of the current time later on
# via localtime.
# So, we're parsing the "yyyy/MM" format once, replace it by, say
# "%04d:%02d" and store an array that says "for the first placeholder,
# get the localtime-parameter on index #5 (which is years since the
# epoch), add 1900 to it and pass it on to sprintf(). For the 2nd
# placeholder, get the localtime component at index #2 (which is hours)
# and pass it on unmodified to sprintf.
# So, the array to compute the time format at logtime contains
# as many elements as the original SimpleDateFormat contained. Each
# entry is a array ref, holding an array with 2 elements: The index
# into the localtime to obtain the value and a reference to a subroutine
# to do computations eventually. The subroutine expects the original
# localtime() time component (like year since the epoch) and returns
# the desired value for sprintf (like y+1900).
# This way, we're parsing the original format only once (during system
# startup) and during runtime all we do is call localtime *once* and
# run a number of blazingly fast computations, according to the number
# of placeholders in the format.
###########
#G - epoch#
###########
if($first eq "G") {
# Always constant
return "AD";
###################
#e - epoch seconds#
###################
} elsif($first eq "e") {
# index (0) irrelevant, but we return time() which
# comes in as 2nd parameter
push @{$self->{stack}}, [0, sub { return $_[1] }];
return "%d";
##########
#y - year#
##########
} elsif($first eq "y") {
if($len >= 4) {
# 4-digit year
push @{$self->{stack}}, [5, sub { return $_[0] + 1900 }];
return "%04d";
} else {
# 2-digit year
push @{$self->{stack}}, [5, sub { $_[0] % 100 }];
return "%02d";
}
###########
#M - month#
###########
} elsif($first eq "M") {
if($len >= 3) {
# Use month name
push @{$self->{stack}}, [4, sub { return $MONTH_NAMES[$_[0]] }];
if($len >= 4) {
return "%s";
} else {
return "%.3s";
}
} elsif($len == 2) {
# Use zero-padded month number
push @{$self->{stack}}, [4, sub { $_[0]+1 }];
return "%02d";
} else {
# Use zero-padded month number
push @{$self->{stack}}, [4, sub { $_[0]+1 }];
return "%d";
}
##################
#d - day of month#
##################
} elsif($first eq "d") {
push @{$self->{stack}}, [3, sub { return $_[0] }];
return "%0" . $len . "d";
##################
#h - am/pm hour#
##################
} elsif($first eq "h") {
push @{$self->{stack}}, [2, sub { ($_[0] % 12) || 12 }];
return "%0" . $len . "d";
##################
#H - 24 hour#
##################
} elsif($first eq "H") {
push @{$self->{stack}}, [2, sub { return $_[0] }];
return "%0" . $len . "d";
##################
#m - minute#
##################
} elsif($first eq "m") {
push @{$self->{stack}}, [1, sub { return $_[0] }];
return "%0" . $len . "d";
##################
#s - second#
##################
} elsif($first eq "s") {
push @{$self->{stack}}, [0, sub { return $_[0] }];
return "%0" . $len . "d";
##################
#E - day of week #
##################
} elsif($first eq "E") {
push @{$self->{stack}}, [6, sub { $WEEK_DAYS[$_[0]] }];
if($len >= 4) {
return "%${len}s";
} else {
return "%.3s";
}
######################
#D - day of the year #
######################
} elsif($first eq "D") {
push @{$self->{stack}}, [7, sub { $_[0] + 1}];
return "%0" . $len . "d";
######################
#a - am/pm marker #
######################
} elsif($first eq "a") {
push @{$self->{stack}}, [2, sub { $_[0] < 12 ? "AM" : "PM" }];
return "%${len}s";
######################
#S - milliseconds #
######################
} elsif($first eq "S") {
push @{$self->{stack}},
[9, sub { substr sprintf("%06d", $_[0]), 0, $len }];
return "%s";
###############################
#Z - RFC 822 time zone -0800 #
###############################
} elsif($first eq "Z") {
push @{$self->{stack}}, [10, sub { $offset }];
return "%s";
#############################
#Something that's not defined
#(F=day of week in month
# w=week in year W=week in month
# k=hour in day K=hour in am/pm
# z=timezone
#############################
} else {
return "-- '$first' not (yet) implemented --";
}
return $string;
}
###########################################
sub format {
###########################################
my($self, $secs, $msecs) = @_;
$msecs = 0 unless defined $msecs;
my @time;
if($GMTIME) {
@time = gmtime($secs);
} else {
@time = localtime($secs);
}
# add milliseconds
push @time, $msecs;
my @values = ();
for(@{$self->{stack}}) {
my($val, $code) = @$_;
if($code) {
push @values, $code->($time[$val], $secs);
} else {
push @values, $time[$val];
}
}
return sprintf($self->{fmt}, @values);
}
1;
__END__
=encoding utf8
=head1 NAME
Log::Log4perl::DateFormat - Log4perl advanced date formatter helper class
=head1 SYNOPSIS
# Either in a log4j.conf file ...
log4perl.appender.Logfile.layout = \
Log::Log4perl::Layout::PatternLayout
log4perl.appender.Logfile.layout.ConversionPattern = %d{MM/dd HH:mm} %m
# ... or via the PatternLayout class ...
use Log::Log4perl::Layout::PatternLayout;
my $layout = Log::Log4perl::Layout::PatternLayout->new(
"%d{HH:mm:ss,SSS} %m");
# ... or even directly with this helper class:
use Log::Log4perl::DateFormat;
my $format = Log::Log4perl::DateFormat->new("HH:mm:ss,SSS");
my $time = time();
print $format->format($time), "\n";
# => "17:02:39,000"
=head1 DESCRIPTION
C<Log::Log4perl::DateFormat> is a helper class for the
advanced date formatting functions in C<Log::Log4perl::Layout::PatternLayout>,
and adheres (mostly) to the log4j SimpleDateFormat spec available on
http://download.oracle.com/javase/1.4.2/docs/api/java/text/SimpleDateFormat.html
It supports the following placeholders:
Symbol Meaning Presentation Example
------ ------- ------------ -------
G era designator (Text) AD
e epoch seconds (Number) 1315011604
y year (Number) 1996
M month in year (Text & Number) July & 07
d day in month (Number) 10
h hour in am/pm (1~12) (Number) 12
H hour in day (0~23) (Number) 0
m minute in hour (Number) 30
s second in minute (Number) 55
S millisecond (Number) 978
E day in week (Text) Tuesday
D day in year (Number) 189
F day of week in month (Number) 2 (2nd Wed in July)
w week in year (Number) 27
W week in month (Number) 2
a am/pm marker (Text) PM
k hour in day (1~24) (Number) 24
K hour in am/pm (0~11) (Number) 0
z time zone (Text) Pacific Standard Time
Z RFC 822 time zone (Text) -0800
' escape for text (Delimiter)
'' single quote (Literal) '
Presentation explanation:
(Text): 4 or more pattern letters--use full form, < 4--use short or
abbreviated form if one exists.
(Number): the minimum number of digits. Shorter numbers are
zero-padded to this amount. Year is handled
specially; that is, if the count of 'y' is 2, the
Year will be truncated to 2 digits.
(Text & Number): 3 or over, use text, otherwise use number.
For example, if you want to format the current Unix time in C<"MM/dd HH:mm">
format, all you have to do is specify it in the %d{...} section of the
PatternLayout in a Log4perl configuration file:
# log4j.conf
# ...
log4perl.appender.Logfile.layout = \
Log::Log4perl::Layout::PatternLayout
log4perl.appender.Logfile.layout.ConversionPattern = %d{MM/dd HH:mm} %m
Same goes for Perl code defining a PatternLayout for Log4perl:
use Log::Log4perl::Layout::PatternLayout;
my $layout = Log::Log4perl::Layout::PatternLayout->new(
"%d{MM/dd HH:mm} %m");
Or, on a lower level, you can use the class directly:
use Log::Log4perl::DateFormat;
my $format = Log::Log4perl::DateFormat->new("MM/dd HH:mm");
my $time = time();
print $format->format($time), "\n";
While the C<new()> method is expensive, because it parses the format
strings and sets up all kinds of structures behind the scenes,
followup calls to C<format()> are fast, because C<DateFormat> will
just call C<localtime()> and C<sprintf()> once to return the formatted
date/time string.
So, typically, you would initialize the formatter once and then reuse
it over and over again to display all kinds of time values.
Also, for your convenience,
the following predefined formats are available, just as outlined in the
log4j spec:
Format Equivalent Example
ABSOLUTE "HH:mm:ss,SSS" "15:49:37,459"
DATE "dd MMM yyyy HH:mm:ss,SSS" "06 Nov 1994 15:49:37,459"
ISO8601 "yyyy-MM-dd HH:mm:ss,SSS" "1999-11-27 15:49:37,459"
APACHE "[EEE MMM dd HH:mm:ss yyyy]" "[Wed Mar 16 15:49:37 2005]"
So, instead of passing
Log::Log4perl::DateFormat->new("HH:mm:ss,SSS");
you could just as well say
Log::Log4perl::DateFormat->new("ABSOLUTE");
and get the same result later on.
=head2 Known Shortcomings
The following placeholders are currently I<not> recognized, unless
someone (and that could be you :) implements them:
F day of week in month
w week in year
W week in month
k hour in day
K hour in am/pm
z timezone (but we got 'Z' for the numeric time zone value)
Also, C<Log::Log4perl::DateFormat> just knows about English week and
month names, internationalization support has to be added.
=head1 Millisecond Times
More granular timestamps down to the millisecond are also supported,
just provide the millsecond count as a second argument:
# Advanced time, resultion in milliseconds
use Time::HiRes;
my ($secs, $msecs) = Time::HiRes::gettimeofday();
print $format->format($secs, $msecs), "\n";
# => "17:02:39,959"
=head1 LICENSE
Copyright 2002-2016 by Mike Schilli E<lt>m@perlmeister.comE<gt>
and Kevin Goess E<lt>cpan@goess.orgE<gt>.
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
=head1 AUTHOR
Please contribute patches to the project on Github:
http://github.com/mschilli/log4perl
Send bug reports or requests for enhancements to the authors via our
MAILING LIST (questions, bug reports, suggestions/patches):
log4perl-devel@lists.sourceforge.net
Authors (please contact them via the list above, not directly):
Mike Schilli <m@perlmeister.com>,
Kevin Goess <cpan@goess.org>
Contributors (in alphabetical order):
Ateeq Altaf, Cory Bennett, Jens Berthold, Jeremy Bopp, Hutton
Davidson, Chris R. Donnelly, Matisse Enzer, Hugh Esco, Anthony
Foiani, James FitzGibbon, Carl Franks, Dennis Gregorovic, Andy
Grundman, Paul Harrington, Alexander Hartmaier David Hull,
Robert Jacobson, Jason Kohles, Jeff Macdonald, Markus Peter,
Brett Rann, Peter Rabbitson, Erik Selberg, Aaron Straup Cope,
Lars Thegler, David Viner, Mac Yang.