I added this line of code
self.auth_history.push [start_date, self.coupon_code]
And got this error message
Date is not currently supported; use a UTC Time instance instead.
I also tried start_date.utc, but it didn't work either.
Please help. Thanks.
I got this answer from Seattle Brigade group -
===
I didn't see start_date defined in your code as a key in MongoMapper, so
I'll assume you're creating your own date object, either directly via Ruby,
or wrapped by Rails. As far as I know, and someone please correct me, Mongo
stores dates as UTC time in milliseconds since epoch. So when you define a
key with a :date mapping in MongoMapper, you're wrapping a Time object in
Ruby.
Therefore, if you want to store a date inside of Mongo, and it wasn't
created by MongoMapper, make sure you create a Time object in UTC.
MongoMapper comes with a Date mixin method called to_mongo that you can use.
>> Time.now.utc
=> Fri Jan 28 03:47:50 UTC 2011
>> require 'date'
=> true
>> date = Date.today
=> #<Date: 4911179/2,0,2299161>
>> Time.utc(date.year, date.month, date.day)
=> Thu Jan 27 00:00:00 UTC 2011
>> require 'rubygems'
=> true
>> require 'mongo_mapper'
=> true
>> Date.to_mongo(date)
=> Thu Jan 27 00:00:00 UTC 2011
But watch out for the time change.
>> Date.to_mongo(Time.now)
=> Thu Jan 27 00:00:00 UTC 2011
>> Date.to_mongo(Time.now.utc)
=> Fri Jan 28 00:00:00 UTC 2011
Good luck.
===
And by using
Date.to_mongo(start_date)
it works for me.
First, I think the question title is bad in description. Actually, the difference between different timezone is on Time not on Date. So, it's really not proper to say I want to convert a date to UTC format.
Here is another way in Ruby to convert DateTime to its UTC format:
DateTime.now.new_offset(0)
Here's another option:
Time.at(Date.today.to_datetime.to_i).utc
Here I am using Date.today as an arbitrary example date. Replace with whatever date you want to convert. Once the date is converted to a Time instance, it can be serialized to BSON without any problem, as Time is a supported primitive type, that is to say, it can be saved using MongoMapper to the database.
As per EfratBlaier's comment I have updated the answer.
Date.today.to_time.utc
Related
We have a simple json API in rails 4 that returns the data using jbuilder. One of the fields is a datetime field "date_of_birth" the json formatting is acting strangely. The same request to the API can randomly generate 2 different results
"date_of_birth":"1989-06-14T20:52:00-07:00"
"date_of_birth":"1989-06-15T03:52:00Z"
As you can see the first one is in local time as the other one is in UTC timezone. We have the timezone globally set to "UTC".
this is the line in the jbuilder view that produces the output, nothing special'
json.array!(#patients) do |patient|
json.extract! patient, :id, :first_name, :last_name, :gender, :groups_code, :date_of_birth
end
What could cause this issue?
Rails is doing some pretty clever work with times in order to cover users with different time-zones and server independent hosting location. Basically times are stored in the database in UTC zone, and converted when needed to the local server/or user time zone.
In a standard Rails app you have 3 times zones that can be the same or can be different: Database time zone, default time zone, and user time zone.
Have a look at this very good article that says it all. Then apply the right method to your date_of_birth field while exporting to json
DOs
2.hours.ago # => Fri, 02 Mar 2012 20:04:47 JST +09:00
1.day.from_now # => Fri, 03 Mar 2012 22:04:47 JST +09:00
Date.today.to_time_in_current_zone # => Fri, 02 Mar 2012 22:04:47 JST +09:00
Date.current # => Fri, 02 Mar
Time.zone.parse("2012-03-02 16:05:37") # => Fri, 02 Mar 2012 16:05:37 JST +09:00
Time.zone.now # => Fri, 02 Mar 2012 22:04:47 JST +09:00
Time.current # Same thing but shorter. (Thank you Lukas Sarnacki pointing this out.)
Time.zone.today # If you really can't have a Time or DateTime for some reason
Time.zone.now.utc.iso8601 # When supliyng an API (you can actually skip .zone here, but I find it better to always use it, than miss it when it's needed)
Time.strptime(time_string, '%Y-%m-%dT%H:%M:%S%z').in_time_zone(Time.zone) # If you can't use Time#parse
DON'Ts
Time.now # => Returns system time and ignores your configured time zone.
Time.parse("2012-03-02 16:05:37") # => Will assume time string given is in the system's time zone.
Time.strptime(time_string, '%Y-%m-%dT%H:%M:%S%z') # Same problem as with Time#parse.
Date.today # This could be yesterday or tomorrow depending on the machine's time zone.
Date.today.to_time # => # Still not the configured time zone.
You may have Time.zone = ... set somewhere based on user time zone setting.
I have seen this same problem and have not been able to figure out why it happens. The other answers here seem to be missing the point that which time format is returned is seemingly random, with no changes to code/config whatsoever.
I was able to "fix" this issue by using .to_time.iso8601 my JBuilder block which will force the 1989-06-15T03:52:00Z format.
In Rails, I see I have a few options to parse a date and a date-time. What is the best practice for parsing dates for the sole purpose of persisting them into the DB via ActiveRecord? And why?
Time.zone.parse(...)
Time.parse(...)
DateTime.parse(...)
Go with Time.zone.parse if you just want to write into ActiveRecord.
DateTime should be avoided. If you're handling dates, you should use Date.parse instead.
Beyond that, it depends on whether the input comes with timezone information, what the current timezone is set to, and whether you want timezones in your data.
Time.zone.parse will return an ActiveSupport::TimeWithZone, defaulting to UTC.
> Time.zone.parse("12:30")
=> Thu, 10 May 2012 12:30:00 UTC +00:00
Time.parse will return a Time, with a zone if it's specified in the input, or the local TZ.
> Time.parse("12:30")
=> 2012-05-09 12:30:00 -0700
For a more detailed explanation of Ruby time comparisons and precision, read this blog post:
http://blog.solanolabs.com/rails-time-comparisons-devil-details-etc/
Times that are automatically set by ActiveRecord (e.g. created_at and updated_at) come back as ActiveSupport::TimeWithZone instances.
According to the documentation, ActiveSupport::TimeWithZone and Time have the same API, so Time is what I would use.
On an unrelated note, there are methods to_time and to_datetime that you can call on strings:
"2012-05-09".to_time # => 2012-05-09 00:00:00 UTC
"2012-05-09".to_datetime # => Wed, 09 May 2012 00:00:00 +0000
In trying to parse a date, I have been racking my brain for hours:
Date.today.to_s
=> "06/07/2011"
Date.today
=> Tue, 07 Jun 2011
Date.parse Date.today.to_s
=> Wed, 06 Jul 2011
Date::DATE_FORMATS[:default]
=> "%m/%d/%Y"
The default format for to_s is different than the default format for parsing? Why would they do this to me?
Using Rails 3.0.5 with Ruby 1.9.2-p180
UPDATE
So thanks to your answers, I realize that the DATE_FORMATS is a rails thing while Date.format is using the ruby library (correct?). Is there a way then to parse dates/times with the default DATE_FORMAT without using strptime?
Normally, Date.today.to_s would return "2011-06-07", but since you set a default date format, it's using "06/07/2011" instead.
Date.parse easily recognizes the YYYY-MM-DD format, but when it sees 06/07/2011 it thinks that's really DD/MM/YYYY (not MM/DD/YYYY as you're expecting -- keep in mind that Date.parse knows nothing about Rails' default date format you set. The default date format is only for Rails' outputting of Date.to_s).
You can force it to parse a MM/DD/YYYY date like this:
Date.strptime(Date.today.to_s, "%m/%d/%Y")
# => Tue, 07 Jun 2011
I would guess that the to_s method uses a locale option to determine how to write the date.
I dont see how this is an issue though. Date.parse uses heuristics to parse the date so sometimes it will get it wrong.
The Chronic gem (link)solves pretty much all date parsing issues (and yes, they can be quite annoying).
Chronic.parse("06/07/2011")
#=> 2011-06-07 12:00:00 +0000
If I have #today = Date.today.to_s, how do I convert #today into UTC (with the appropriate date only)?
Here I need is only date for example 2011-03-08 ie 08 March 2011. Please suggest something ?
Acutally I am looking for Yesterday date ??
You'll need to convert it to a Time object (or just use Time anyway) and then call Time#utc:
irb > Time.now
=> Tue Mar 08 15:32:36 +1100 2011
irb > Time.now.utc
=> Tue Mar 08 04:32:40 UTC 2011
You can then format it however you need it:
irb > #today = Time.now.utc
=> Tue Mar 08 04:34:25 UTC 2011
irb > #today.strftime("%Y-%m-%d")
=> "2011-03-08"
If you want to convert #today into UTC.
Then try this
>> #today = Date.today.to_s
>> DateTime.parse(#today)
Try
1.day.ago.utc
or
1.day.ago.utc.strftime('%b %B, %Y')
The format below should give you the date format of Yesterday which you are looking for formatted as 07 March, 2011. Look into the ruby Time class manual for more information on strftime time formating function. Good luck!
I strongly recommend you to move towards time zones in rails. Its easier and lot more convenient to work with than Time.now. You should be able to set the time zone in environment.rb with config.time_zone = "Chennai" or your time zone. After doing this, you should be able to get the time with UTC information by Doing Time.zone.now. To find the UTC offset, you could type Time.zone.
I have a rails time-based query which has some odd timezone sensitive behaviour, even though as far as I know I'm using UTC. In a nutshell, these queries give different answers:
>> Model.find(:all,:conditions=>['created_at<=?',(Time.now-1.hours).gmtime]).length
=> 279
>> Model.find(:all,:conditions=>['created_at<=?',(Time.now-1.hours)]).length
=> 280
Where the DB actually does contain one model created in the last hour, and the total number of models is 280. So only the first query is correct.
However, in environment.rb I have:
config.time_zone = 'UTC'
The system time zone (as reported by 'date') is BST (which is GMT+1) - so somehow this winds up getting treated as UTC and breaking queries.
This is causing me all sorts of problems as I need to parameterise the query passing in different times to an action (which are then converted using Time.parse()), and even though I send in UTC times, this 'off by one hour' DST issue crops a lot. Even using '.gmtime()' doesn't always seem to fix it.
Obviously the difference is caused somehow by an implicit conversion somewhere resulting in BST being incorrectly treated as UTC, but why? Doesn't rails store the timestamps in UTC? Isn't the Time class timezone aware? I am using Rails 2.2.2
So what is going on here - and what is the safe way to program around it?
edit, some additional info to show what the DB and Time class are doing:
>> Model.find(:last).created_at
=> Tue, 11 Aug 2009 20:31:07 UTC +00:00
>> Time.now
=> Tue Aug 11 22:00:18 +0100 2009
>> Time.now.gmtime
=> Tue Aug 11 21:00:22 UTC 2009
The Time class isn't directly aware of your configured timezone. Rails 2.1 added a bunch of timezone support, but Time will still act upon your local timezone. This is why Time.now returns a BST time.
What you likely want is to interact with Time.zone. You can call methods on this like you would the Time class itself but it will return it in the specified time zone.
Time.zone.now # => Tue, 11 Aug 2009 21:31:45 UTC +00:00
Time.zone.parse("2:30 PM Aug 23, 2009") # => Sun, 23 Aug 2009 14:30:00 UTC +00:00
Another thing you have to be careful with is if you ever do queries on the database where you are comparing times, but sure to use the UTC time (even if you have a different time zone specified) because Rails always stores UTC in the database.
Item.all(:conditions => ["published_at <= ?", Time.now.utc])
Also, instead of Time.now-1.hour do 1.hour.ago. It is easier to read and Rails will automatically use the configured timezone.
The TimeZone you need to set is UK, this will automatically handle BST
Time.zone = 'UK'
Time.zone.now
=> Sun, 17 Oct 2010 02:09:54 BST +01:00
start_date_format = DateTime.strptime(#start_date, date_format)
start_date_format_with_hour =
DateTime.strptime((start_date_format.to_i + timezone_offset*60*60).to_s,'%s').strftime(date_format)
end_date_format = DateTime.strptime(#end_date, date_format)
end_date_format_with_hour = DateTime.strptime((end_date_format.to_i + timezone_offset*60*60).to_s,'%s').strftime(date_format)
#filters_date = "invoices.created_at >= ? AND invoices.created_at < ?", start_date_format_with_hour, end_date_format_with_hour