Hi chrisr, The document is misleading. Only DataSet api support prefixed print now. I create a jira for DataStream[1]. For now, you can use a customed SinkFunction to achieve this.
[1]. https://issues.apache.org/jira/browse/FLINK-9850 On Sat, Jul 14, 2018 at 10:34 PM, chrisr123 <chris.rueg...@gmail.com> wrote: > > The documentation states that there is a way to specify a prefix msg to > distinguish between different calls to print() (see below), but I have not > found a way to do this? Can anyone show me how I would code this? > > What I'd like to do conceptually, and have the prefix msg show up in the > output so I know where I am > in the transformation process: > > DataStream<String> myStream = ... > myStream.print("beforeFilter"); > > > DataStream<String> myFilteredStream = myStream.filter(new MyFilter()); > myFilteredStream.print("afterFilter"); > > > From Docs: > print() / printToErr() - Prints the toString() value of each element on the > standard out / standard error stream. Optionally, a prefix (msg) can be > provided which is prepended to the output. This can help to distinguish > between different calls to print. If the parallelism is greater than 1, the > output will also be prepended with the identifier of the task which > produced > the output. > > > > -- > Sent from: http://apache-flink-user-mailing-list-archive.2336050. > n4.nabble.com/ >
