Hi , You've got a point. I saw that method, but how can I make sure that all the subtasks checkpoint are finished, because I can only write _SUCCESS file at that time.
Best, Ben > On 5 Feb 2018, at 6:34 PM, Fabian Hueske <fhue...@gmail.com> wrote: > > In case of a failure, Flink rolls back the job to the last checkpoint and > reprocesses all data since that checkpoint. > Also the BucketingSink will truncate a file to the position of the last > checkpoint if the file system supports truncate. If not, it writes a file > with the valid length and starts a new file. > > Therefore, all files that the BucketingSink finishes must be treated as > volatile until the next checkpoint is completed. > Only when a checkpoint is completed a finalized file may be read. The files > are renamed on checkpoint to signal that they are final and can be read. This > would also be the right time to generate a _SUCCESS file. > Have a look at the BucketingSink.notifyCheckpointComplete() method. > > Best, Fabian > > > > > 2018-02-05 6:43 GMT+01:00 xiaobin yan <yan.xiao.bin.m...@gmail.com > <mailto:yan.xiao.bin.m...@gmail.com>>: > Hi , > > I have tested it. There are some small problems. When checkpoint is > finished, the name of the file will change, and the success file will be > written before checkpoint. > > Best, > Ben > > >> On 1 Feb 2018, at 8:06 PM, Kien Truong <duckientru...@gmail.com >> <mailto:duckientru...@gmail.com>> wrote: >> >> Hi, >> >> I did not actually test this, but I think with Flink 1.4 you can extend >> BucketingSink and overwrite the invoke method to access the watermark >> Pseudo code: >> invoke(IN value, SinkFunction.Context context) { >> long currentWatermark = context.watermark() >> long taskIndex = getRuntimeContext().getIndexOfThisSubtask() >> if (taskIndex == 0 && currentWatermark - lastSuccessWatermark > 1 hour) { >> Write _SUCCESS >> lastSuccessWatermark = currentWatermark round down to 1 hour >> } >> invoke(value) >> } >> >> Regards, >> Kien >> On 1/31/2018 5:54 PM, xiaobin yan wrote: >>> Hi: >>> >>> I think so too! But I have a question that when should I add this logic in >>> BucketingSink! And who does this logic, and ensures that the logic is >>> executed only once, not every parallel instance of the sink that executes >>> this logic! >>> >>> Best, >>> Ben >>> >>>> On 31 Jan 2018, at 5:58 PM, Hung <unicorn.bana...@gmail.com> >>>> <mailto:unicorn.bana...@gmail.com> wrote: >>>> >>>> it depends on how you partition your file. in my case I write file per >>>> hour, >>>> so I'm sure that file is ready after that hour period, in processing time. >>>> Here, read to be ready means this file contains all the data in that hour >>>> period. >>>> >>>> If the downstream runs in a batch way, you may want to ensure the file is >>>> ready. >>>> In this case, ready to read can mean all the data before watermark as >>>> arrived. >>>> You could take the BucketingSink and implement this logic there, maybe wait >>>> until watermark >>>> reaches >>>> >>>> Best, >>>> >>>> Sendoh >>>> >>>> >>>> >>>> -- >>>> Sent from: >>>> http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/ >>>> <http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/> > >