perl code:
#!/bin/env perl
use DateTime;
print DateTime->now;
OUTPUT:
2013-01-28T06:02:33
what's mean of 'T' letter in the output string ?
ISO8601 and RFC3339 both use "T" to join the date and the time, and DateTime's default stringifier apparently adopted that convention. If you want another format, you can use one of the DateTime::Format::* modules or ->strftime.
my $now = DateTime->now( time_zone => 'local' );
say $now->strftime('%Y-%m-%d %H:%M:%S');
It stands for "Time". You can read more at:
http://en.wikipedia.org/wiki/ISO_8601#Combined_date_and_time_representations
It's the separator between date and time in ISO 8601. It's always a T in this format.
The character [T] shall be used as time designator to indicate the start of the representation of the time of day
component in these expressions. The hyphen [-] and the colon [:] shall be used, in accordance with 4.4.4, as
separators within the date and time of day expressions, respectively, when required.
NOTE By mutual agreement of the partners in information interchange, the character [T] may be omitted in
applications where there is no risk of confusing a date and time of day representation with others defined in this
International Standard.
--Data elements and interchange
formats — Information interchange —
Representation of dates and times, ISO 8601:2004(E)
Related
I am looking to convert timestamps such as the following
2019-01-01T02:15:00+00:00
Into Australian Eastern Standard Time in Perl.
I have over 10,000 of these timestamps, any help would be really appreciated
I need to input them into a mysql DB with a format of YYYY-MM-DD hh:mm:ss
You would use the standard Perl module Time::Piece. It provides the standard strptime and strftime functions. The first allows you to parse a timestamp with a template and the second outputs a timestamp based on the same kind of template. To change timezones you would add or subtract the number of seconds difference.
$t = Time::Piece->strptime("2020-11-04T01:46:00", "%Y-%m-%dT%H:%M:%S");
$t += $offset;
print $t->strftime("%Y-%m-%dT%H:%M:%S");
Or if your current time is the current locale and you're always converting from GMT:
$t = Time::Piece->strptime("2020-11-04T01:46:00", "%Y-%m-%dT%H:%M:%S");
$l = localtime $t->epoch;
print $l->strftime("%Y-%m-%dT%H:%M:%S");
Now if you need to do something more complicated than that (daylight savings time, leap seconds), there is the DateTime module but it is correspondingly far more complicated to use.
See also How can I parse dates and convert time zones in Perl?
HTH
With java.time , I'm trying to format the time as the following "2018-03-15T23:47:15+01:00" .
With this formatter I'm close to the result in Scala.
val formatter: DateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ssZ")
ZonedDateTime.now() // 2018-03-14T19:25:23.397+01:00
ZonedDateTime.now().format(formatter) // => 2018-03-14 19:25:23+0100
But I cannot insert the extra character "T" between the day and hour.
What does this "T" mean BTW ?
How to format as "2018-03-15T23:47:15+01:00" ?
Notes:
In case you wonder why LocalDateTime cannot be formatted
Format LocalDateTime with Timezone in Java8
Try this
val ZONED_DATE_TIME_ISO8601_FORMATTER3 = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSSxxx")
ZonedDateTime.now().format(ZONED_DATE_TIME_ISO8601_FORMATTER3)
// 2018-03-14T19:35:54.321+01:00
See here
Offset X and x: This formats the offset based on the number of pattern letters. One letter outputs just the hour, such as '+01', unless the minute is non-zero in which case the minute is also output, such as '+0130'. Two letters outputs the hour and minute, without a colon, such as '+0130'. Three letters outputs the hour and minute, with a colon, such as '+01:30'. Four letters outputs the hour and minute and optional second, without a colon, such as '+013015'. Five letters outputs the hour and minute and optional second, with a colon, such as '+01:30:15'. Six or more letters throws IllegalArgumentException. Pattern letter 'X' (upper case) will output 'Z' when the offset to be output would be zero, whereas pattern letter 'x' (lower case) will output '+00', '+0000', or '+00:00'.
Converting the ZonedDateTime to OffsetDateTime - as suggested in the other answers - works, but if you want to use a DateTimeFormatter, there's a built-in constant that does the job:
ZonedDateTime.now().format(DateTimeFormatter.ISO_OFFSET_DATE_TIME)
But it's important to note some differences between all the approaches. Suppose that the ZonedDateTime contains a date/time equivalent to 2018-03-15T23:47+01:00 (the seconds and milliseconds are zero).
All the approaches covered in the answers will give you different results.
toString() omits seconds and milliseconds when they are zero. So this code:
ZonedDateTime zdt = // 2018-03-15T23:47+01:00
zdt.toOffsetDateTime().toString()
prints:
2018-03-15T23:47+01:00
only hour and minute, because seconds and milliseconds are zero
The built-in formatter will omit only the milliseconds if it's zero, but it'll print the seconds, regardless of the value. So this:
zdt.format(DateTimeFormatter.ISO_OFFSET_DATE_TIME)
prints:
2018-03-15T23:47:00+01:00
seconds printed, even if it's zero; milliseconds ommited
And the formatter that uses an explicit pattern will always print all the fields specified, regardless of their values. So this:
zdt.format(DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSSxxx"))
prints:
2018-03-15T23:47:00.000+01:00
seconds and milliseconds are printed, regardless of their values
You'll also find a difference in values such as 2018-03-15T23:47:10.120+01:00 (note the 120 milliseconds). toString() and ofPattern will give you:
2018-03-15T23:47:10.120+01:00
While the built-in DateTimeFormatter.ISO_OFFSET_DATE_TIME will print only the first 2 digits:
2018-03-15T23:47:10.12+01:00
Just be aware of these details when choosing which approach to use.
As your question already shows, you may just rely on ZonedDateTime.toString() for getting a string like 2018-03-14T19:25:23.397+01:00. BTW, that string is in ISO 8601 format, the international standard. Only two minor modifications may be needed:
If you don’t want the fraction of second — well, I don’t see what harm it does, it agrees with ISO 8601, so whoever receives your ISO 8601 string should be happy to have it. But if you don’t want it, you may apply myZonedDateTime.truncatedTo(ChronoUnit.SECONDS) to get rid of it.
ZonedDateTime.toString() often appends a zone name, for example 2018-03-14T19:25:23+01:00[Europe/Paris], which is not part of the ISO 8601 standard. To avoid that, convert to OffsetDateTime before using its toString method: myZonedDateTime.toOffsetDateTime().toString() (or myZonedDateTime.truncatedTo(ChronoUnit.SECONDS).toOffsetDateTime().toString()).
Building your own formatter through a format pattern string is very flexible when this is what you need. However, very often we can get through with less (and then should do for the easier maintainability of our code): toString methods or built-in formatters including both the ISO ones and the localized ones that we can get from DateTimeFormatter.ofLocalizedPattern().
What does this "T" mean BTW ?
The T is part of the ISO 8601 format. It separates the date part from the time-of-day part. You may think of it as T for time since it denotes the start of the time part. If there is only a date (2018-04-25) or only a time-of-day (21:45:00), the T is not used, but when we have both, the T is required. You may think that the format might have been specified without the T, and you are probably right. When it comes to the format for periods/durations it is indispensable, however, and also needed when there are no days: P3M means a period of 3 months, while PT3M means 3 minutes.
Link: Read more in the Wikipedia article on ISO 8601.
My collegue (who has left the company) has written a bunch of scripts, including batch and Perl scripts, and I'm getting rid of the regional settings dependencies.
In the last Perl script, he's written the following piece of code:
my $format = "%d.%m.%Y %H:%M";
my $today_converted = Time::Piece->strptime($today, $format) - ONE_HOUR - ONE_HOUR - ONE_HOUR - ONE_HOUR - ONE_HOUR;
(the idea is to get five hours before midnight of that particular date)
The value of $today seems to be "03/04/2017" (which stands for the third of April (European dateformat)), which seems not to be understood by Time::Piece implementation:
Error parsing time at C:/Perl64/lib/Time/Piece.pm line 481.
Which format can I use which is understood by Time::Piece Perl implementation?
In the format you have dots . as the date delimiter, but in the data you have slashes /. That's why it doesn't parse. It needs an exact match.
I think it's worth clarifying that strptime() will parse most date and time formats - that's the point of the method. But you need to define the format of the date string that you are parsing. That's what the second parameter to strptime() (in this case, your $format variable) is for.
The letters used in the format are taken from a standard list of definitions which used by every implementation of strptime() (and its inverse, strftime()). See man strptime on your system for a complete list of the available options.
In your case, the format is %d.%m.%Y %H:%M - which means that it will parse timestamps which have the day, month and year separated by dots, followed by a space and the hours and minutes separated by a colon. If you want to parse timestamps in a different format, then you will need to change the definition of $format.
Disclaimer: you might need to install
a font/typeface which supports
Japanese if you see messed up
characters.
I'm trying to replicate what I've been doing so far with setlocale and strftime:
setlocale(LC_ALL, 'ja_JP.utf8');
$time = mktime();
echo strftime('%x', $time), '<br>';
Output:
2010年01月06日
Using Zend_Date - but I haven't been able to reproduce the same formatting with the japanese symbols for year, month and day.
Attempt #1:
$locale = new Zend_Locale('ja_JP');
$date = new Zend_Date( strtotime('yesterday'), null, $locale);
//echo $date->toString('YYYY abcdefghijklmnopqrstuvwxy M dE');
echo $date->get('YYYY MMM DD');
Output:
2010 1月 004
Attempt #2:
echo $date->get(Zend_Date::DATE_FULL);
Output:
2010年1月5日火曜日
My first attempt I can't seem to find a working constant to produce the YEAR and day symbols. The latter uses a standardized format but I need to customize it so there's a 0 preceding the month, and I want to be more in control.
In the future I may want to make it flexible so for example, en_US dates won't have those letters coming after the year/month/day but it would only apply to languages such as Japanese and others, where it's more common, or if I misunderstood and it isn't really common then please inform me.
Thanks in advance.
Seems what I needed was the DATE_LONG constant, which internally points to 'FFFF' - I'm trying to learn the inner workings of how the Date class corresponds with the Locale class to generate the whole string including the symbols now.
Update: I kept trying to find where it actually used date units instead of date formats, found the right data I need:
<dateFormatLength type="long">
<dateFormat>
<pattern>y年M月d日</pattern>
</dateFormat>
</dateFormatLength>
So it parses this and replaces the y, M, d, returns the formatted date.
In Perl, localtime takes a Unix timestamp and gives back year/month/day/hour/min/sec etc. I'm looking for the opposite of localtime: I have the parts, and I'd like to build a unix timestamp from them.
You can use the timelocal function in the Time::Local CPAN module.
NAME
Time::Local - efficiently compute time
from local and GMT time
SYNOPSIS
$time = timelocal($sec,$min,$hour,$mday,$mon,$year);
$time = timegm($sec,$min,$hour,$mday,$mon,$year);
DESCRIPTION
This module provides functions that
are the inverse of built-in perl
functions localtime() and gmtime().
They accept a date as a six-element
array, and return the corresponding
time(2) value in seconds since the
system epoch (Midnight, January 1,
1970 GMT on Unix, for example). This
value can be positive or negative,
though POSIX only requires support for
positive values, so dates before the
system's epoch may not work on all
operating systems.
It is worth drawing particular
attention to the expected ranges for
the values provided. The value for the
day of the month is the actual day (ie
1..31), while the month is the number of months since January (0..11). This
is consistent with the values returned
from localtime() and gmtime().
Note: POSIX::mktime is a just a wrapper around your C library's mktime() function. Time::Local is a pure-Perl implementation, and always returns results matching Perl's localtime. Also, Time::Local offers gmtime, while mktime only works in local time. (Well, you could try changing $ENV{TZ}, but that doesn't work on some systems.)
POSIX::mktime
DateTime on CPAN might of of some use. It also has a lot of time manipulation/translation methods.
Just create the DateTime using your parts and call $datetime->formatter("%s") ;