1. If we have multiple sources, can the streams be parallelized ? 2. Can we have multiple sinks as well?
On Dec 14, 2016 10:46 PM, <dromitl...@gmail.com> wrote: > Got it. Thanks! > > On Dec 15, 2016, at 02:58, Jamie Grier <ja...@data-artisans.com> wrote: > > Ahh, sorry, for #2: A single Flink job can have as many sources as you > like. They can be combined in multiple ways, via things like joins, or > connect(), etc. They can also be completely independent — in other words > the data flow graph can be completely disjoint. You never to need to call > execute() more than once. Just define you program, with as many sources as > you want, and then call execute(). > > val stream1 = env.addSource(...)val stream2 = env.addSource(...) > > stream1 > .map(...) > .addSink(...) > > stream2 > .map(...) > .addSink(...) > > env.execute() // this is all you need > > > > On Wed, Dec 14, 2016 at 4:02 PM, Matt <dromitl...@gmail.com> wrote: > >> Hey Jamie, >> >> Ok with #1. I guess #2 is just not possible. >> >> I got it about #3. I just checked the code for the tumbling window >> assigner and I noticed it's just its default trigger that gets overwritten >> when using a custom trigger, not the way it assigns windows, it makes sense >> now. >> >> Regarding #4, after doing some more tests I think it's more complex than >> I first thought. I'll probably create another thread explaining more that >> specific question. >> >> Thanks, >> Matt >> >> On Wed, Dec 14, 2016 at 2:52 PM, Jamie Grier <ja...@data-artisans.com> >> wrote: >> >>> For #1 there are a couple of ways to do this. The easiest is probably >>> stream1.connect(stream2).map(...) where the MapFunction maps the two >>> input types to a common type that you can then process uniformly. >>> >>> For #3 There must always be a WindowAssigner specified. There are some >>> convenient ways to do this in the API such at timeWindow(), or >>> window(TumblingProcessingTimeWindows.of(...)), etc, however you always >>> must do this whether your provide your own trigger implementation or not. >>> The way to use window(...) with and customer trigger is just: >>> stream.keyBy(...).window(...).trigger(...).apply(...) or something >>> similar. Not sure if I answered your question though.. >>> >>> For #4: If I understand you correctly that is exactly what >>> CountWindow(10, 1) does already. For example if your input data was a >>> sequence of integers starting with 0 the output would be: >>> >>> (0) >>> (0, 1) >>> (0, 1, 2) >>> (0, 1, 2, 3) >>> (0, 1, 2, 3, 4) >>> (0, 1, 2, 3, 4, 5) >>> (0, 1, 2, 3, 4, 5, 6) >>> (0, 1, 2, 3, 4, 5, 6, 7) >>> (0, 1, 2, 3, 4, 5, 6, 7, 8) >>> (0, 1, 2, 3, 4, 5, 6, 7, 8, 9) >>> (1, 2, 3, 4, 5, 6, 7, 8, 9, 10) >>> (2, 3, 4, 5, 6, 7, 8, 9, 10, 11) >>> (3, 4, 5, 6, 7, 8, 9, 10, 11, 12) >>> (4, 5, 6, 7, 8, 9, 10, 11, 12, 13) >>> ... >>> etc >>> >>> -Jamie >>> >>> >>> On Wed, Dec 14, 2016 at 9:17 AM, Matt <dromitl...@gmail.com> wrote: >>> >>>> Hello people, >>>> >>>> I've written down some quick questions for which I couldn't find much >>>> or anything in the documentation. I hope you can answer some of them! >>>> >>>> *# Multiple consumers* >>>> >>>> *1.* Is it possible to .union() streams of different classes? It is >>>> useful to create a consumer that counts elements on different topics for >>>> example, using a key such as the class name of the element, and a tumbling >>>> window of 5 mins let's say. >>>> >>>> *2.* In case #1 is not possible, I need to launch multiple consumers >>>> to achieve the same effect. However, I'm getting a "Factory already >>>> initialized" error if I run environment.execute() for two consumers on >>>> different threads. How do you .execute() more than one consumer on the same >>>> application? >>>> >>>> *# Custom triggers* >>>> >>>> *3.* If a custom .trigger() overwrites the trigger of the >>>> WindowAssigner used previously, why do we have to specify a WindowAssigner >>>> (such as TumblingProcessingTimeWindows) in order to be able to specify a >>>> custom trigger? Shouldn't it be possible to send a trigger to .window()? >>>> >>>> *4.* I need a stream with a CountWindow (size 10, slide 1 let's say) >>>> that may take more than 10 hours fill for the first time, but in the >>>> meanwhile I want to process whatever elements already generated. I guess >>>> the way to do this is to create a custom trigger that fires on every new >>>> element, with up to 10 elements at a time. The result would be windows of >>>> sizes: 1 element, then 2, 3, ..., 9, 10, 10, 10, .... Is there a way to >>>> achieve this with predefined triggers or a custom trigger is the only way >>>> to go here? >>>> >>>> Best regards, >>>> Matt >>>> >>> >>> >>> >>> -- >>> >>> Jamie Grier >>> data Artisans, Director of Applications Engineering >>> @jamiegrier <https://twitter.com/jamiegrier> >>> ja...@data-artisans.com >>> >>> >> > > > -- > > Jamie Grier > data Artisans, Director of Applications Engineering > @jamiegrier <https://twitter.com/jamiegrier> > ja...@data-artisans.com > >
