Rails datetime_select posting my current time in UTC

问题

I'm trying to compare what the user selects for a start date and end date to the current time to prevent the user from selecting a time in the past. It works except you have to pick a time, in my case, 4 hours ahead in order for it to pass the validation.

View:

datetime_select(:start_date, ampm: true)

Controller:

if self.start_date < DateTime.now || self.end_date < DateTime.now
  errors.add(:date, 'can not be in the past.')
end

self.start_date is returning my current time but in utc which is wrong. DateTime.now is returning my current time but with an offset of -0400 which is correct.

Example:

My current time is 2013-10-03 09:00:00.000000000 -04:00

self.start_date is 2013-10-03 09:00:00.000000000 Z

DateTime.now is 2013-10-03 09:00:00.000000000 -04:00

Why is this happening and what would be the best way to fix it?

回答1:

you can do something like this

around_filter :set_time_zone

private

def set_time_zone
  old_time_zone = Time.zone
  Time.zone = current_user.time_zone if logged_in?
  yield
ensure
  Time.zone = old_time_zone
end

you can also do this

adding following to application.rb works

 config.time_zone = 'Eastern Time (US & Canada)'
 config.active_record.default_timezone = 'Eastern Time (US & Canada)'

回答2:

I ended up fixing it by converting the start_date to a string and back to time. It was weird that I needed :local, as the documentation on to_time says it is the default, but it only works when it is present.

def not_past_date

  current_time = DateTime.now
  start_date_selected = self.start_date.to_s.to_time(:local)
  end_date_selected = self.start_date.to_s.to_time(:local)

  if start_date_selected < current_time || end_date_selected < current_time
    errors.add(:date, 'can not be in the past.')
  end
end

来源：https://stackoverflow.com/questions/19163176/rails-datetime-select-posting-my-current-time-in-utc

标签

ruby-on-rails

ruby

datetime

timezone