Last week I started to sketch out what would be involved in building a
calendar app in Rails. In the process I went looking for what Ruby
has in the way of Date/Time libraries, and in particular TimeZone
support. Was (pleasantly?) surprised to find that Rails seems to have
Ruby''s best timezone support. But it looks like it has a very serious
bug, it isn''t daylight saving aware.
Timezones are a serious pain in the ass, but leaving out the weird
edge cases, and dropping support for historical dates, but without DST
support you find problems like:
Eastern Time (I''m in Boston) is listed as being 18_000 seconds offset
from UTC, but as of 2am this morning, we''re only 14_400 seconds from
UTC.
So if I''ve got an application where I''m saving items with
created_at
in UTC (ActiveRecord::Base.default_timezone = :utc), but I want to be
able to display the created times in a user''s local time, so
I''ve got
some code like (where @user_tz is an instance of Rails TimeZone)
<%= @user_tz.adjust(@item.created_at) %>
This code was working up until 2am this morning, but as of today all
of my created times are an hour off.
Another minor bug is that the Time returned from adjust() will still
report itself as being in UTC. (this could be that I''m not using these
libraries with their proper idioms)
Not sure what the best approach to fixing it is. To fix this bug one
would need to add a either a rule engine, or a dependency on zoneinfo.
It seems like really it would be best if all this was added to Ruby''s
Date/DateTime modules rather then in Rails, but I couldn''t speculate
as to the communities interest.
Thanks
-kellan
