How reduce one day from current in Pipeline Jenkins? - jenkins-pipeline

Question

I can't reduce one day from current
def now = new Date();
print(now); // print Fri Sep 06 13:10:03 EEST 2019
print(now - 1.days); // not working
print(now - 1); // not working
Please help me. Thanks in advance

Answer 1

the solution works. There might be 2 problems though:
- the snippet you wrote has to be included in a script if you plan to execute it in a stage
- the DateGroovyMethods is not allowed to be used by default. You need administrator rights and to check the build log to allow the execution of that stuff.
The error will look like this:
Scripts not permitted to use staticMethod org.codehaus.groovy.runtime.DateGroovyMethods minus java.util.Date int. Administrators can decide whether to approve or reject this signature.
This is my test example:
pipeline {
agent any
stages {
stage('MyDate test') {
steps {
script {
def date = new Date()
print date
print date - 1
}
}
}
}
}
EDIT:
If you are not an administrator, you can replace the script block with sh 'date -d "-1 days"'

Answer 2

You can also use minus(1) instead of - 1:
def now = new Date();
print(now);
print(now.minus(1))

Answer 3

The best thing to do is to skip the use of Date entirely. java.util.Date is literally the oldest java implementation of date and time. The newest comes with Java 8. You can do it like this:
groovy:000> java.time.LocalDateTime.now().minusDays(1)
===> 2019-09-08T12:07:30.835557
groovy:000>
You can convert from Date to LocalDateTime as well if needed.

Answer 4

(Java syntax used here, as I do not know Groovy.)
tl;dr
Subtract 24-hours.
Instant.now().minus( Duration.ofHours( 24 ) ) // UTC.
…or…
Subtract one calendar day.
ZonedDateTime.now( ZoneId.of( "America/New_York" ) ).minusDays( 1 ) ) // Time zone for Toledo, Ohio, US.
java.time
Never use java.util.Date. That terrible class was supplanted years ago by the modern java.time classes with the adoption of JSR 310. Specifically replaced by Instant.
I can't reduce one day from current
What do you mean by “one day”?
Generic 24-hour days
Do you mean to subtract 24-hours?
Duration d = Duration.ofHours( 24 ) ;
Instant instant = Instant.now() ;
Instant twentyFourHoursAgo = instant.minus( d ) ;
The Instant class represents a moment in UTC with a resolution of nanoseconds.
Run this code live at IdeOne.com.
instant.now().toString(): 2019-09-09T18:48:17.106438Z
twentyFourHoursAgo.toString(): 2019-09-08T18:48:17.106438Z
Calendar days
Do you mean to subtract one calendar day?
This requires a time zone. For any given moment, the date varies around the globe by time zone. It may be “tomorrow” in Tokyo Japan while still “yesterday” in Toledo Ohio US.
Specify a time zone with ZoneId to capture the current moment as seen through the wall-clock time used by the people of a particular region in a ZonedDateTime object.
ZoneId z = ZoneId.of( "Asia/Tokyo" ) ;
ZonedDateTime zdt = ZonedDateTime.now( z ) ;
ZonedDateTime oneDayAgo = zdt.minusDays( 1 ) ;
Run this code live at IdeOne.com.
zdt.toString(): 2019-09-10T03:48:17.147539+09:00[Asia/Tokyo]
oneDayAgo.toString(): 2019-09-09T03:48:17.147539+09:00[Asia/Tokyo]
Convert
If you must have a java.util.Date object to interoperate with old code not yet updated to java.time, you can convert. See the new to…/from… conversion methods added to the old classes.
java.util.Date javaUtilDate =
Date.from( Instant.now().minus( Duration.ofHours( 24 ) ) ) ;
…or…
java.util.Date javaUtilDate =
Date.from( ZonedDateTime.now( ZoneId.of( "Asia/Tokyo" ) ).minusDays( 1 ) ) ) ;
Keep in mind that java.util.Date.toString method tells a lie, dynamically applying the JVM’s current default time zone while generating the text. One of many reasons to avoid this badly-designed class.