In perl, how do I convert date like
Thu Mar 06 02:59:39 +0000 2008
to
2008-03-06T02:59:39Z
Tried HTTP::Date, it works if the question did not have +0000 in the string :(
DateTime::Format::Strptime will do this conversion.
#!/usr/bin/perl
use strict;
use warnings;
use 5.012;
use DateTime::Format::Strptime;
my $date = 'Thu Mar 06 02:59:39 +0000 2008 ';
my( #strp ) = (
DateTime::Format::Strptime->new( pattern => "%a %b %d %T %z %Y", ),
DateTime::Format::Strptime->new( pattern => "%FY%T%Z", )
);
my $dt = $strp[0]->parse_datetime( $date );
print $strp[1]->format_datetime( $dt );
prints 2008-03-06T02:59:39UTC
Chris
If you're absolutely, positively sure that the date will ALWAYS be in that format, you can simply use regular expressions to reformat it. The only thing is that you have to have a way of converting the month to a number. That way, you don't have to download any extra modules to do the date conversion:
my $date = "Thu Mar 06 02:59:39 +0000 2008"; #Original String
#Create the Month Hash (you might want all twelve months).
my %monthHash (Jan => "01", Feb => 2, Mar => 3);
# Use RegEx Matching to parse your date.
# \S+ means one or more non-spaces
# \s+ means one or more spaces
# Parentheses save that part of the string in $1, $2, $3, etc.
$date =~ m/\S+\s+(\S+)\s+(\S+)\s+(\S+)\s+\S+\s(.*)/;
my $monthString = $1;
my $day = $2;
my $time = $3;
my $year = $4;
# Convert Month string to a number.
my $month = $monthHash{$monthString};
#Reformat the string
$fmtDate="$year-$month-$day" . "T" . "$time" . "Z";
Otherwise I was going to say you can also try DateTime::Format::Strptime, but Chris Charley beat me to it.
So, edit it with a regex and use HTTP::Date:
( my $new_date_string = $old_state_string ) =~ s/[+-]\d{4,}\s+//;
Related
I am trying to convert hex time(getting first output from kernel module) into nanosecond granularity,
580a9272.0a9ce167
and I am trying to convert it using perl into human readable format:
while (<>) {
s/^([a-fA-F0-9]+)(\.)([a-fA-F0-9]+)(\s+.*)/sprintf("%s%s%s%s",&$converter(hex($1)), $2, hex($3), $4)/oe;
} continue {
print;
}
output : Fri Oct 21 18:10:58 2016.178053479
Converter uses localtime() and gmtime() directly
I want time with nano granularity and then year.Any help is highly appreciated.
POSIX::strftime doesn't support fractional seconds, so you need to build the output in parts.
use POSIX qw( strftime );
my $opt_gmt = 1;
my $hex = '580a9272.0a9ce167';
my ($s, $ns) = map hex($_), split /\./, $hex;
my $formatted_ns = sprintf("%09d", $ns);
my $formatted = strftime("%a %b %d %H:%M:%S.$formatted_ns %Y",
defined($opt_gmt) ? gmtime($s) : localtime($s));
say $formatted; # Fri Oct 21 22:10:58.178053479 2016
DateTime has native support for nanoseconds, so that presents an alternative.
use DateTime qw( );
my $opt_gmt = 1;
my $hex = '580a9272.0a9ce167';
my ($s, $ns) = map hex($_), split /\./, $hex;
my $dt = DateTime->from_epoch( epoch => $s );
$dt->set_nanosecond( $ns );
$dt->set_time_zone( defined($opt_gmt) ? 'UTC' : 'local' );
say $dt->strftime("%a %b %d %H:%M:%S.%N %Y"); # Fri Oct 21 22:10:58.178053479 2016
In my program I have the user input a date in the format of "Month Day" (example May 25) and I want to be able to print an error message if it is an invalid date (example February 30).
So here's some code
$start_date = ARGV[0];
my $year = DateTime->now->year; # adds a year to the date
my $date_parser = DateTime::Format::Strptime->new(pattern => '%Y %B %d', # YYYY Month DD
);
my $start_epoch = $date_parser->parse_datetime("$year $start_date")->epoch();
Right after this I need some kind of if statement right?
If the date is invalid, then the parser will return undef. You will see this quite quickly if you do:
my $start_date = "Feb 30";
my $year = DateTime->now->year; # adds a year to the date
my $date_parser = DateTime::Format::Strptime->new(pattern => '%Y %B %d', # YYYY Month DD
);
my $start_epoch = $date_parser->parse_datetime("$year $start_date")->epoch();
The solution:
my $parsed = $date_parser->parse_datetime("$year $start_date");
if ( not defined $parsed ) { print "Error - invalid date\n"; }
From perlmonks:
use Time::Local;
my $date = ' 19990230'; # 30th Feb 1999
$date =~ s/\s+$//;
$date =~ s/^\s*//;
my ($year, $month, $day) = unpack "A4 A2 A2", $date;
eval{
timelocal(0,0,0,$day, $month-1, $year); # dies in case of bad date
+
1;
} or print "Bad date: $#";
This should do you justice
i want to convert the date time format to that i want.
how to convert the date time format from Fri Nov 21 2014 15:04:32 to 2014-11-21 15:04:32 ?
thanks
Time::Piece has been core Perl for many years.
Use strptime (string parse time) to parse your date/time string.
Use strftime (string format time) to format your date/time as you want it.
#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
use Time::Piece;
# Formats are defined in "man strftime"
my $in_fmt = '%a %b %d %Y %H:%M:%S';
my $out_fmt = '%Y-%m-%d %H:%M:%S';
my $in_date = 'Fri Nov 21 2014 15:04:32';
my $date = Time::Piece->strptime($in_date, $in_fmt);
my $out_date = $date->strftime($out_fmt);
say $out_date;
my $str = 'Fri Nov 21 2014 15:04:32';
my #months =('jan','feb','mar','apr','may','jun','jul','aug','sep','oct','nov','dec');
my ($day,$mon,$date,$year,$time) = split(' ',lc($str));
my %month_hash;
#month_hash{#months} = (1 .. 12);
print "$year-$month_hash{$mon}-$date $time";
try this its crude method but works for your requirements. use date::manip for flexible usage
I want to get the system clock (time and date) and display it in a human-readable format in Perl.
The format like 2014-09-12 15:13:56
#!/usr/local/bin/perl
my %months = qw(Jan Feb Mar Apr May Jun Jul
Aug Sep Oct Nov Dec);
#weekDays = qw(Sun Mon Tue Wed Thu Fri Sat Sun);
($second, $minute, $hour, $dayOfMonth, $month, $yearOffset, $dayOfWeek, $dayOfYear,
$daylightSavings) = localtime();
$year = 1900 + $yearOffset;
$now = "$year-$months-$dayOfMonth $hour:$minute:$second";
print $now;
When you run the program, you should see a much more readable date and time like this:
2014--12 16:57:15
how to get convert the month to number ?
Using Time::Piece (core module since perl v5.9.5)
use Time::Piece;
my $dt = localtime;
print $dt->ymd, " ", $dt->hms, "\n";
using DateTime
use DateTime;
my $dt = DateTime->now();
print $dt->ymd, " ", $dt->hms, "\n";
It's easier using a Perl module (POSIX doesn't requires installation):
use POSIX qw/strftime/;
my $now_string = strftime "%Y-%m-%d %H:%M:%S", localtime;
print $now_string, "\n"; #<-- prints: 2014-09-12 11:09:45 (with my local time)
Regarding to your code, there is a typo:
$now = "$year-$months-$dayOfMonth $hour:$minute:$second";
should be:
$now = "$year-$month-$dayOfMonth $hour:$minute:$second";
Be sure to write use strict; and use warnings; in the top place of your script. It prevents you from errors like that.
I like to put these date and time tasks into functions for reuse.
Here is my approach:
use strict;
use warnings;
my $time_stamp = getTodaysDateTime();
print "Program Started: $time_stamp \n";
# do some processing
$time_stamp = getTodaysDateTime();
print "Program Ended: $time_stamp \n";
# return date in specific format
# ex: 2014-09-12 14:11:43
sub getTodaysDateTime {
my ($sec,$min,$hour,$mday,$mon,$year,
$wday,$yday,$isdst) = localtime(time);
$year += 1900;
$mon += 1;
return sprintf("%d-%02d-%02d %02d:%02d:%02d",
$year,$mon,$mday,$hour,$min,$sec);
}
Using this function:
perl -e 'use Time::Local; print timelocal("00","00","00","01","01","2000"),"\n";'
It will return an epochtime - but only in GMT - if i want the result in GMT+1 (which is the systems localtime(TZ)), what do i need to change?
Thanks in advance,
Anders
use DateTime;
my $dt = DateTime->now;
$dt->set_time_zone( 'Europe/Madrid' );
There is only one standard definition for epochtime, based on UTC, and not different epochtimes for different timezones.
If you want to find the offset between gmtime and localtime, use
use Time::Local;
#t = localtime(time);
$gmt_offset_in_seconds = timegm(#t) - timelocal(#t);
While Time::Local is a reasonable solution, you may be better off using the more modern DateTime object oriented module. Here's an example:
use strict;
use DateTime;
my $dt = DateTime->now;
print $dt->epoch, "\n";
For the timezones, you can use the DateTime::TimeZone module.
use strict;
use DateTime;
use DateTime::TimeZone;
my $dt = DateTime->now;
my $tz = DateTime::TimeZone->new(name => "local");
$dt->add(seconds => $tz->offset_for_datetime($dt));
print $dt->epoch, "\n";
CPAN Links:
DateTime
You just need to set the timezone. Try:
env TZ=UTC+1 perl -e 'use Time::Local; print timelocal("00","00","00","01","01","2000"),"\n";'
Time::Local::timelocal is the inverse of localtime. The result will be in your host's local time:
$ perl -MTime::Local -le \
'print scalar localtime timelocal "00","00","00","01","01","2000"'
Tue Feb 1 00:00:00 2000
Do you want the gmtime that corresponds to that localtime?
$ perl -MTime::Local' -le \
'print scalar gmtime timelocal "00","00","00","01","01","2000"'
Mon Jan 31 23:00:00 2000
Do you want it the other way around, the localtime that corresponds to that gmtime?
$ perl -MTime::Local -le \
'print scalar localtime timegm "00","00","00","01","01","2000"'
Tue Feb 1 01:00:00 2000
An other example based on DateTime::Format::Strptime
use strict;
use warnings;
use v5.10;
use DateTime::Format::Strptime;
my $s = "2016-12-22T06:16:29.798Z";
my $p = DateTime::Format::Strptime->new(
pattern => "%Y-%m-%dT%T.%NZ",
time_zone => "UTC"
);
my $dt = $p->parse_datetime($s);
$dt->set_time_zone("Europe/Berlin");
say join ' ', $dt->ymd, $dt->hms; # shows 2016-12-22 07:16:29
The Algorithm
If you want to change a time value from one timezone to another timezone, you must be able to indicate both timezones.
After all, if you set if you want to convert "12:30" to GMT or US/Eastern or Venezuelan time, which means adding/subtracting some amount of hours or hours and minutes, you need to know what timezone is the starting time zone, otherwise, the calculation won't know how much to add or subtract.
If you use DateTime->now;, the timezone is defaulted to the system-time, which may not be the timezone you want to convert from.
In the below code, I demonstrate how to initialize the datetime object to the right starting timezone (fromtimezone) and how to convert that time to the ending timezone (totimezone)...
Working Code
I could not find a Perl sandbox online with the DateTime CPAN module installed.
use strict;
use DateTime;
sub convertTimeZonesForTime {
my ($args) = #_;
my $time = $args->{time};
my $date = $args->{date};
my $totimezone = $args->{totimezone};
my $fromtimezone = $args->{fromtimezone};
my $format = $args->{format} || '%H:%M:%S';
my ($year, $month, $day) = map {int $_} split('-', $date);
my ($hour, $minute, $second) = map {int $_} split(':', $time);
$year ||= 1999 if !defined $year;
$month ||= 1 if !defined $month;
$day ||= 1 if !defined $day;
$hour ||= 12 if !defined $hour;
$minute ||= 30 if !defined $minute;
$second ||= 0 if !defined $second;
my $dt = DateTime->new(
year=>$year,
month=>$month,
day=>$day,
hour=>$hour,
minute=>$minute,
second=>$second,
time_zone => $fromtimezone,
);
my $formatter = new DateTime::Format::Strptime(pattern => $format);
$dt->set_formatter($formatter);
$dt->set_time_zone($totimezone);
return "$dt";
}
print(convertTimeZonesForTime({
'totimezone'=>'America/Denver',
'fromtimezone'=>'US/Eastern',
'time'=>'12:30:00',
}));
Output:
10:30:00