Thank you Matthias. Those detailed instructions will come in handy for
me - when/if I get that far.
The problem I mentioned a couple of emails ago in this thread was in the
IDE - haven\t yet got as far as doing it on the server.
I tested out the TimeZone library with a couple of randomly chosen
timezones - and they all came back incorrect (i.e. unchanged from UTC
even though the timezones should have been different). I know that if
you pass in a timezone that is not in the local machine's database, it
will silently return the UTC value - but that's not the case here.
I've now looked at it more closely - some of these timezones give the
right answer, some give the wrong answer - though they are all in the
TimeZones() list.
All on my MacBook Pro, OSX 10.13.6, LC 9.6 ...
local tTimeZones, tAllTheTimeZones
put timezones() into tAllTheTimeZones
put "UTC" & CR after tTimeZones
put "America/New_York" & CR after tTimeZones
put "America/Anchorage" & CR after tTimeZones
put "junktotest" & CR after tTimeZones
put "US/Central" & CR after tTimeZones
put "US/Alaska" & CR after tTimeZones
repeat for each line L in tTimeZones
if L is among the lines of tAllTheTimeZones then
put L && FromUniversalTime(the seconds,L) &CR after msg
else
put L && "is not in the database" &CR after msg
end if
end repeat
gives
UTC 1604762435
America/New_York 1604744435
America/Anchorage 1604730035
junktotest is not in the database
US/Central 1604762435
US/Alaska 1604762435
Note the last two (which happened to be the ones I chose in my earlier
test) wrongly show the UTC time, though they are clearly in the
TimeZones() list.
Maybe just a bug and I should report it ?
Alex
On 07/11/2020 14:36, matthias rebbe via use-livecode wrote:
Alex,
i've posted already some info about how to use the time zone library in Livecode server
in my comment to David's post "Aw: Basic question: Time Zone Library".
Here it is again and a little bit more detailed.
1. copy the folder com.livecode.library.timezone from the LC extensions folder
to your webserver into a folder extensions. The extensions folder can be found
in the App Bundle on macOS or in the windows program folder
e.g. C:\Program Files (x86)\RunRev\LiveCode Business 9.6.1
2. place your .lc script in the same folder where the extensions folder exists.
3. configure/set the path where the shared library for your server os is
located (see line 3 in the sample script below)
4. load the extension module.lcm (see line 4 in the sample script below)
The following script uses the time zone library to output the available time
zones
<?lc
put the folder into tBasePath
set the revLibraryMapping["tz"] to tBasePath
&"/extensions/com.livecode.library.timezone/code/x86_64-linux/tz.so"
load extension from file tBasePath &
"/extensions/com.livecode.library.timezone/module.lcm"
put timezones() into tTZ
replace return with "<br>" in tTZ
put tTZ
?>
-
Matthias Rebbe
Life Is Too Short For Boring Code
Am 07.11.2020 um 13:57 schrieb Alex Tweedly via use-livecode
<use-livecode@lists.runrev.com>:
Thanks Graham. That does indeed work - on your local system.
The issue I am trying to deal with (and maybe it's related to what David is
doing) is dealing with time zone issues on a LC web server. If you want to
timestamp when some event happens, you can do that as a UTC timestamp using a
function like this one of yours; but that leaves you two problems.
- presenting those timestamps back to the user - which should be in *their*
local time
- allowing the user to provide their own timestamp - again should be local
for them.
Most advice I've found via Google, etc. suggests keeping the timestamps in UTC,
and asking the user to provide their timezone - usually when they 'register'.
You can then use PHP (or ...) functions to convert a date/time between UTC and
their local zone.
You might hope to do that in LC using 'convert .. to internet date' - but that
doesn't work because that conversion (seems to) assume a local time, and then
simply fill in the time offset for the local system (i.e. the problem David
reported).
You should be able to do it using the TimeZone library - but I haven't figured
out how to to do that, or I'm using it wrong, or something. (I didn't know
about the Timezone library until David mentioned it yesterday.)
I'm currently using an ugly (though working :-) workaround using e.g.
put "America/New_York" into timeZone
*put*shell("TZ=" & timeZone & " date") into tmp
and working it all out from there (assumes Unix server - don't know if it works
on others).
Alex.
On 07/11/2020 10:27, Graham Samuel via use-livecode wrote:
I am as confused as anyone else as to what you are trying to do, but just in
case, this little function seems to work for me to get the ’standard’ UTC date
format which I have to use in my app to put time stamps into GPX files. It
apparently produces the correct time zone. Doubtless it could be more elegantly
coded.
Hope it helps - who knows?
Graham
function fUTCTime
local t1,t2,t3
-- this gets the current time and puts it into UTC format, i.e
YYYY-MM-DDThh:mm:ssTZD
put word 5 to 6 of the internet date into t3 -- we are interested in the
time and time zone
put the long time into t1
convert t1 to dateItems -- format is yyyy,m,d,h,m,s,day no.
put (item 1 of t1) & "-" & f2digits(item 2 of t1) & "-" & f2digits(item 3 of t1)
&"T" & word 1 of t3 into t2
put word 2 of t3 into t1 -- the time zone indication
get char 1 of t1 — the code for 0 (zero) is Z, apparently
if it <> "+" and it <> "-“ then
put "Z" after t2
else
put t1 after t2
end if
return t2
end fUTCTime
function f2digits theNum
-- add a leading zero. We don't check if there are more than two digits
if number of chars of theNum = 1 then
return ("0" & theNum)
else
return theNum
end if
end f2digits
On 7 Nov 2020, at 01:34, Alex Tweedly via use-livecode
<use-livecode@lists.runrev.com> wrote:
I don't think it "strips" the TZ info - it simply ignores it. I think the key
phrase is in the dictionary as :
*Note:* The *convert* command assumes all dates / times are in local time
except for 'the seconds', which is taken to be universal time.
So it assume syou date is in local time (regardless of the +0300), and therefore your
example returns +0000 for you (I assume you're in the UK, or equivalent, now). It does
the same for me, and returns the date with "+0000".
However, the same code run on my LC server (wherever on-rev is these days),
changes the +0300 to -0500 - i.e. it's taken as local time where the server is.
I assume you should be able to do something with the TimeZone library - but I'm
struggling to figure that out.
local tNow
put the seconds into tNow
put FromUniversalTime(tNow,"US/Central") into tt
put tNow && tt
put FromUniversalTime(tNow,"US/Alaska") into tt
put CR & tt after msg
gives me
1604709030 1604709030
1604709030
so I don't have a clue what it was trying to do !?!
Alex.
On 06/11/2020 21:28, David Bovill via use-livecode wrote:
Why does:
get "Fri, 06 Nov 2020 10:57:37 +0300"
convert it to internet date
put it
— give
"Fri, 06 Nov 2020 10:57:37 +0000"
Just seems to strip the timezone info?
On 30 Oct 2020, 21:29 +0000, How to use LiveCode
<use-livecode@lists.runrev.com>, wrote:
ToUniversalTime
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