How to save dates in local timezone to db with rails3? - ruby-on-rails

I have Rails3 application with model user and field expires_at created like this:
t.column :expires_at, :timestamp
In my database (postgresql) it has type:
timestamp without timezone
The problem is when I call:
#user.expires_at = Time.now
#user.save
it is saved into database with UTC timezone (my local time is UTC + 1:00, Warsaw) but I don't want that. I just want to have time with my local timezone saved into the database (2011-03-30 01:29:01.766709, not 2011-03-29 23:29:01.766709)
Can I achieve this using rails3?

For saving time in local timezone to database this has to be set in application.rb
config.active_record.default_timezone = :local

If you only want to use local times on certain columns, rather than as a global setting, then the Rails documentation tells us this:
# If your attributes are time zone aware and you desire to skip time zone conversion to the current Time#zone when reading certain attributes then you can do following:
class Topic < ActiveRecord::Base
self.skip_time_zone_conversion_for_attributes = [:written_on]
end
(This also skips time zone conversion on writing, not just reading). And you can pass in an array of symbols for multiple attributes.
I am not sure which versions of Rails this was introduced in, though.

Related

Rails - How to save datetimes correctly in MongoID and trigger them with whenerver (cronjobs)?

I try to save datetimes into events in MongoDB with Mongoid. The difficulty is that I want to save them for different timezones (e.g. Berlin and London). I want the user (admin) to see the actual time in the timezone so that he does not need to calculate. Afterwards I have a cron job in whenever, which looks every minute for an event to process.
I have the following parameters:
application.rb (I tried without -> standard UTC -> London is ok, Berlin wrong hour)
config.time_zone = 'Berlin' # as the server stays in Germany
mongoid.yml (tried all combinations, need use_activesupport_time_zone to get correct times int oDB though)
use_activesupport_time_zone: true
use_utc: false
schedule.rb (no problem here so far)
every 1.minutes do
runner "Event.activate_due", environment: 'development'
end
event.rb (not sure for which times I am looking now)
def self.activate_due
events_due = Event.where(:eventStart.lte => (Time.now + 1.minute), :eventStart.gte => (Time.now))
events_due.each do |e|
e.activate
end
end
I tried to change the Time.zone in events#new in order to depict the timezone's actual time in the simple_form. It seems to work, but then the controller create method seems to treat the params as standard time zone again and transforms it wrongly (+-1hour when experimenting with London/Berlin). I tried out almost every parameter combination and also Time.now/Time.zone.now.
In event#index I switch through time_zones in order to show the right time.
To complicate things a bit: I save the timezone in the area model, which is connected through areaId with the event model.
How would I show the admin in the form the correct time for the event in the zone he wants to add (not his timezone) and save it correctly in Mongo to trigger it through the cronjob later?
Try the following
def self.activate_due
events_due = Event.where(
:eventStart.to_utc.lte =>(Time.now.to_utc),
:eventStart.to_utc.gte => (1.minute.ago.to_utc))
events_due.each do |e|
e.activate
end
end
Plesse note that this will work with UTC times, so if you have an event in UTC - 7 timezone don't think it will get activated now if the server timezone is UTC + 2

Ruby on Rails - Handling of DateTime.current and User Input Time

I'm using Rails 3.2.9 with Postgres database and JRuby 1.7.12.
Application is running Ubuntu Server with GMT+7 Asia/Bangkok Time Zone.
config.time_zone is set to Bangkok
Postgres timezone is also set to Asia/Bangkok
In my invoice model, I have 2 datetime fields called document_date and movement_date
-> movement_date is generated by application using DateTime.current
-> document_date is input by the User (i.e 2014-07-28)
When User save the Invoice, both will be converted to UTC and saved into Database.
for movement_date, it is fine (as this is the expected behaviour)
for document_date, when it is convert to UTC, it will be saved as 2014-07-27 17:00.
How can I save document_date to 2014-07-28 00:00 into database without converting to UTC.
Your Help, Advise, Suggestion would be highly appreciated and Many Thanks in advance.
If there are any additional info I should add, kindly let me know.
EDIT: the field in postgresql for both is using Timestamp Without Time Zone
If i understood it correctly, you want the document_date (which is an user input) to be in UTC, rather than in your local time. Is it correct? If so, you'll have to change it manually, as Rails makes the assumption that you want it in your local time.
What you could do is set it manually, converting the date string to datetime (String#to_datime), just before the object saving on your controller. Something like that:
def create
#invoice = Invoice.new(params[:invoice])
#invoice.document_date = params[:invoice][:document_date].to_datetime
#invoice.save
end
String#to_datetime will create a UTC DateTime as long as the string doesn't have Time and TimeZone parts on it (ie: "2014-07-28 00:00:00 +0700" will be converted to Bangkok DateTime).

How to present Rails form datetime select in different time zone?

I would like to present a datetime select to the user in their preferred time zone but store the datetime as UTC. Currently, the default behavior is to display and store the datetime field using UTC. How can I change the behavior of this field without affecting the entire application (i.e. not changing the application default time zone)?
Update: This is not a per-user timezone. I don't need to adjust how times are displayed. Only these specific fields deal with a different time zone, so I would like the user to be able to specify the time in this time zone.
Here's how you can allow the user to set a date using a specific time zone:
To convert the multi-parameter attributes that are submitted in the form to a specific time zone, add a method in your controller to manually convert the params into a datetime object. I chose to add this to the controller because I did not want to affect the model behavior. You should still be able to set a date on the model and assume your date was set correctly.
def create
convert_datetimes_to_pdt("start_date")
convert_datetimes_to_pdt("end_date")
#model = MyModel.new(params[:my_model])
# ...
end
def update
convert_datetimes_to_pdt("start_date")
convert_datetimes_to_pdt("end_date")
# ...
end
def convert_datetimes_to_pdt(field)
datetime = (1..5).collect {|num| params['my_model'].delete "#{field}(#{num}i)" }
if datetime[0] and datetime[1] and datetime[2] # only if a date has been set
params['my_model'][field] = Time.find_zone!("Pacific Time (US & Canada)").local(*datetime.map(&:to_i))
end
end
Now the datetime will be adjusted to the correct time zone. However, when the user goes to edit the time, the form fields will still display the time in UTC. To fix this, we can wrap the fields in a call to Time.use_zone:
Time.use_zone("Pacific Time (US & Canada)") do
f.datetime_select :start_date
end
There are a couple of options:
Utilize the user's local timezone when displaying data to them. This is really easy with something like the browser-timezone-rails gem. See https://github.com/kbaum/browser-timezone-rails. It is essentially overriding the application timezone for each request based on the timezone detected from the browser. NOTE: it only uses the OS timezone, so it's not as accurate as an IP/geo based solution.
Setup your application timezone so that it is consistent with the majority of your user base. For example: config.time_zone = 'Mountain Time (US & Canada)'. This is a very standard thing to do in rails. Rails will always store the data in the DB as UTC, but will present / load it using the application timezone.
Create a timezone for your user model. Allow users to set this value in their account settings. And, then use a similar approach to that of the above gem does in the application_controller.

Get hour from user and store in rails model + timezone

I have a rails view where the user is presented with a dropdown displaying the hours '00:00', '01:00' etc.
Once the user has selected this hour, then it is stored in the model with some other fields.
My application is working in timezone UTC+2 (I have set config.time_zone = 'Jerusalem').
At what stage to I related to timezones when handling this time on its path from the view to the model? If I use e.g. DateTime.strptime("10:00", "%H:%M").in_time_zone(Time.zone), then I get a time at '12:00' - while what I really would like is for the database to store in UTF (which should be 08:00 while the rest of the site works with local time.
You can use TZInfo ruby library http://tzinfo.rubyforge.org and convert your time with following method
def local_to_utc(date, time_zone)
begin
unless time_zone.nil?
tz = TZInfo::Timezone.get(time_zone)
return tz.local_to_utc(date)
end
rescue
return nil
end
end

time_select with 12 hour time and Time Zone in Ruby on Rails

I have the need to capture a time and time zone from users of a rails 2.3.8 app, but have been unable to think of a clean solution to create and parse the selections.
Ideally I would have a drop-down menus for the following:
hour (1-12)
minute (0-59)
AM/PM
Time Zone
Is there a gem/plugin that accomplishes what I am looking for? Will I need to store both the time and time zone in the database? What is the best strategy for storage?
I'll eventually need to spit these values out in UTC, but a user should be able to go back and review the time in the correct time zone.
You can get time zone selects with the appropriate methods:
time_zone_options_for_select
time_zone_select
Similarly, there's date_select for dates.
Storage:
If the timezone is specific to the user and doesn't change, then store their time zone in their user record and set it when you load the current_user. Rails will convert times to/from UTC and always store UTC in the database and do the automatic convert to that default timezone for you (including daylight savings!). Easiest way to do it.
use_zone(zone) lets you override the default zone for a block, so you can accept a form value and set it with that function and set your value in that block.
UPDATE: I wrote up some Rails timezone examples as a blog entry.
I personally used jQuery to change the display only:
ampm = ["12 AM","01 AM","02 AM","03 AM","04 AM","05 AM","06 AM","07 AM","08 AM","09 AM","10 AM","11 AM","12 PM","01 PM","12 PM","01 PM","02 PM","01 PM","02 PM","03 PM","04 PM","05 PM","06 PM","07 PM","08 PM","09 PM","10 PM","11 PM"]
j("#game_start_time_4i option").each(function(index,value){
j(value).html(ampm[index]);
});
Rails:
<%= datetime_select('game', 'start_time') %>

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