Sorry, I mistakenly thought that we were on the Java driver mailing list, my apologies. I also think you should definitely file a Jira ticket and ask JSON timestamps generated server-side to be 1) formatted with a format that mentions the timezone and 2) formatted preferably with UTC, not the JVM default timezone.
Alexandre On Mon, Feb 8, 2016 at 12:23 PM Ralf Steppacher <ralf.viva...@gmail.com> wrote: > Hi Alexandre. > > I wrote to ‘user@cassandra.apache.org’. > > Re the actual problem: I am aware of the fact that C* does not store (need > not store) the timezone as it is persisted as a Unix epoche timestamp. Not > delivering a timezone in the JSON text representation would be OKish if the > text representation would be guaranteed to be in UTC. But it is not. It is > in some timezone determined by the locale of the server side or that of the > client VM. That way it is a pain in two ways as > > a) I have to add the timezone in a post-processing step to all timestamps > in my JSON responses and > b) I also have to do some guesswork at what the actual timezone might be > > If there is no way to control the formatting of JSON timestamps and to add > the time zone information, then IMHO that is bug. Is it not? Or am I > missing something here? > > > Thanks! > Ralf > > > On 08.02.2016, at 12:06, Alexandre Dutra <alexandre.du...@datastax.com> > wrote: > > Hello Ralf, > > First of all, Cassandra stores timestamps without timezone information, so > it's not possible to retrieve the original timezone used when inserting the > value. > > CQLSH uses the python driver behind the scenes, and my guess is that the > timestamp formatting is being done driver-side – hence the timezone – while > when you call toJson(), the formatting has to be done server-side. > > That said, it does seem that Cassandra is using a format without timezone > when converting timestamps to JSON format: > > https://github.com/apache/cassandra/blob/cassandra-3.0/src/java/org/apache/cassandra/serializers/TimestampSerializer.java#L52 > > I agree with you that a date format that would include the timezone would > be preferable here, but that is a question you should ask in the Cassandra > Users mailing list instead. > > Hope that helps, > > Alexandre > > > > > On Mon, Feb 8, 2016 at 11:09 AM Ralf Steppacher <ralf.viva...@gmail.com> > wrote: > >> Hello all, >> >> When I select a timestamp as JSON from Cassandra, the string >> representation lacks the timezone information, both via CQLSH and the Java >> Driver: >> >> cqlsh:events> select toJson(created_at) AS created_at from >> event_by_patient_timestamp ; >> >> created_at >> --------------------------- >> "2016-01-04 16:05:47.123" >> >> (1 rows) >> >> vs. >> >> cqlsh:events> select created_at FROM event_by_user_timestamp ; >> >> created_at >> -------------------------- >> 2016-01-04 15:05:47+0000 >> >> (1 rows) >> cqlsh:events> >> >> To make things even more complicated the JSON timestamp is not returned >> in UTC. Is there a way to either tell the driver/C* to return the JSON date >> in UTC or add the timezone information (much preferred) to the text >> representation of the timestamp? >> >> >> Thanks! >> Ralf > > -- > Alexandre Dutra > Driver & Tools Engineer @ DataStax > > > -- Alexandre Dutra Driver & Tools Engineer @ DataStax
