In my view I’m displaying a timestamp of when an IPS event occurred <%=
event[:timestamp] %>. The timestamp in the database is correct, but what
is
displayed is four hours in the future… Why is this being changed, and
how
can I just have it display the actual timestamp?
On Jul 21, 2014, at 1:22 PM, [email protected] wrote:
In my view I’m displaying a timestamp of when an IPS event occurred <%=
event[:timestamp] %>. The timestamp in the database is correct, but what is
displayed is four hours in the future… Why is this being changed, and how can I
just have it display the actual timestamp?
Time zones. What db are you using? What is the type on the column you
use to save the timestamp? How sure are you that it is correct in the
database? (IOW, do you understand whether the db treats it as UTC or not
tied to any time zone, and do you understand how whatever software
you’re using to look at it is interpreting it?)
–
Scott R.
[email protected]
http://www.elevated-dev.com/
(303) 722-0567 voice
PostgreSQL, and it’s in UTC. I’m just looking to display what is in the
database, something is adding 4 hours. Using select * from event; in the
database shows the right info.
On Jul 21, 2014, at 1:49 PM, [email protected] wrote:
PostgreSQL, and it’s in UTC.
What do you mean “it’s in UTC”? Is the column type timestamp with time
zone, or timestamp without time zone?
–
Scott R.
[email protected]
http://www.elevated-dev.com/
(303) 722-0567 voice
On 21 July 2014 20:22, [email protected] wrote:
In my view I’m displaying a timestamp of when an IPS event occurred <%=
event[:timestamp] %>
By simply displaying it like that you are letting the system work out
how to display it. If you want to display it in the format you want
then use the appropriate formatting helper.
Colin
On Jul 21, 2014, at 3:04 PM, [email protected] wrote:
Sorry, looks like timestamp with TZ.
OK. So it’ timestamp with TZ, and when you select from the db using
psql, you see the correct time? Postgres is translating back and forth
between the time zone configured on the server on which it is running
and UTC. So if that server is at UTC-400, then the values stored can
appear to be 4 hours ahead if they’re not correctly offset to local time
or formatted correctly. (I wanted confirmation from you about that,
because although I suspected you just needed to get a value from UTC
into the local timezone, I’ve seen cases where things were configured
such that there were multiple fubar’s relating to timezone handling,
with the timestamps stored incorrectly, and multiple offsets, so that
just adding an offset from UTC to local might appear to be a fix, but
would in fact just be one more offset piled on top of others that were
incorrect.)
So, first puts mytimestamp.inspect, just to make 100% sure what RoR sees
as the underlying value. My working theory is that it’s the correct
moment in time, but UTC.
Then, assuming that is actually the case:
http://api.rubyonrails.org/v4.1.1/classes/ActiveSupport/TimeWithZone.html
And note that in /config/application.rb you can set the default time
zone to something other than UTC:
config.time_zone = ‘Central Time (US & Canada)’
(Use ActiveSupport::TimeZone.zones_map to get a list of available time
zones.)
The config options is useful for in-house type of application where all
users can reasonably be assumed to be in the same time zone (or at
least, want to view all times in the same time zone). For an app which
will be used across time zones, you’d have to track preferred time zones
by user, develop some helper methods or filters or whatever to use the
custom time zones per user, and even worse, potentially display
timestamps based on criteria beyond just the user’s time zone…
–
Scott R.
[email protected]
http://www.elevated-dev.com/
(303) 722-0567 voice
Sorry, looks like timestamp with TZ.