As a clarifying question: If you have three elements in the pane with timestamps [1, 4, 5], would you: A. want to emit that entire pane when the watermark passes 1 B. want to emit that entire pane when the watermark passes 5 C. emit a fragment of that pane containing only the first element when the watermark passes 1
On Thu, Dec 1, 2016 at 6:01 PM Tyler Akidau <taki...@google.com> wrote: > So what you want is essentially a trigger that fires when the watermark > has passed the event time of the oldest un-emitted element in the current > pane? You could them presumably wrap this in a repeat to get the overall > desired semantics, right? > > -Tyler > > > On Fri, Dec 2, 2016 at 7:32 AM Manu Zhang <owenzhang1...@gmail.com> wrote: > > My use case is to track user trajectory based on page view event when they > visit a website. The input would be like a list of PageView(userId, url, > eventTimestamp) with watermarks (= eventTimestamp - duration). I'm trying > Sessions with event time trigger. Note we can't wait for the end of session > window due to latency requirement. Instead, we want to emit the user > trajectories whenever a buffered PageView's event time is passed by > watermark. > > On Fri, Dec 2, 2016 at 5:41 AM Lukasz Cwik <lc...@google.com> wrote: > > Can you provide more details about the problem your trying to solve with > some examples showing input and the expected output? > > > > > On Wed, Nov 30, 2016 at 11:08 PM, Manu Zhang <owenzhang1...@gmail.com> > wrote: > > Hi, > > Recently I’m addressing a problem where users want to trigger after > watermark past each element (i.e. in the middle of event-time window). I > fail to find an existing trigger that does so. Any idea on model this > problem with Beam ? > > Thanks, > Manu Zhang > > >
