Heroku console weird date issue

I have a cron task that runs once a day, using Heroku's Daily Cron addon. The cron takes values from yesterday's data and creates required objects with today's timestamp. But, I am facing unusual circumstances. This is from Heroku console :

>> Date.today
=> Thu, 25 Aug 2011
>> Date.yesterday
=> Thu, 25 Aug 2011
>> DateTime.now
=> Thu, 25 Aug 2011 23:31:42 -0700

The current time being 23:31, I thought of giving it a try later on. This is what I have now :

>> Date.today
=> Fri, 26 Aug 2011
>> Date.开发者_如何学运维yesterday
=> Thu, 25 Aug 2011
>> DateTime.now
=> Fri, 26 Aug 2011 00:35:14 -0700

Any ideas why Date.today and Date.yesterday provide the same result. Is it due to the timezone or other certain settings ?

Thanks

Date.today represents date according to your server time irrespective of the time zone that you have set.

Date.yesterday is Time.now.in_time_zone - 1.day. It depends on Time.zone that we have set

This example should clarify it:

ruby-1.9.2-p180 :014 > Time.now => 2011-08-26 03:21:10 +0545

ruby-1.9.2-p180 :015 > Time.zone => (GMT+00:00) UTC

ruby-1.9.2-p180 :016 > Time.now.in_time_zone => Thu, 25 Aug 2011 21:36:40 UTC +00:00

ruby-1.9.2-p180 :018 > Date.yesterday => Wed, 24 Aug 2011

ruby-1.9.2-p180 :017 > Date.today => Fri, 26 Aug 2011

Now,after setting time-zone as Kathmandu. Date.yesterday changes as expected but there is no change to Date.today

ruby-1.9.2-p180 :019 > Time.zone="Kathmandu" => "Kathmandu"

ruby-1.9.2-p180 :022 > Time.now.in_time_zone => Fri, 26 Aug 2011 03:55:28 NPT +05:45

ruby-1.9.2-p180 :020 > Date.yesterday=> Thu, 25 Aug 2011

ruby-1.9.2-p180 :021 > Date.today => Fri, 26 Aug 2011

Date.Today is the default method provided by ruby. Date.Yesterday though is not a ruby method but is provided by Rails as part of its core extensions.

Date.Yesterday returns Date.current.yesterday

Date.Current as quoted from rails documentation,

Returns Time.zone.today when Time.zone or config.time_zone are set, otherwise just returns Date.today

It seems this is the reason why you are getting the same date for both the methods.

It's problaby a TimeZone issue.

I'm developing in Spring Boot and I'm using the code below in the main class:

@PostConstruct
    public void init() {
        TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
    }

And when generate a Date, LocalDate, LocalDateTime or Instant use:

public static Instant getInstantNow() {
        Clock utcClock = Clock.systemUTC();
        return Instant.now(utcClock).minusSeconds(10800);//my local comparing to UTC in seg.
    }

    public static LocalDateTime getLocalDateTimeNow() {
        ZonedDateTime nowBrasil = ZonedDateTime.now(ZoneId.of("Brazil/East"));
        return LocalDateTime.from(nowBrasil);
    }

    public static LocalDate getLocalDateNow() {
        ZonedDateTime nowBrasil = ZonedDateTime.now(ZoneId.of("Brazil/East"));
        return LocalDate.from(nowBrasil);
    }