Dear Philippe, that is exactly what i need. Thank you for the concise explanation.
This approach is excellent, as it also permits the values to be easily updated externally. Kind regards Leon 30. May 2016 14:31 by philippe.capar...@orange.fr: > > > Just transform the list in a DataStream. A datastream can be finite. > > > One solution, in the context of a Streaming environment is to use Kafka, or > any other distributed broker, although Flink ships with a KafkaSource. > > > > 1)Create a Kafka Topic dedicated to your list of key/values. Inject your > values into this topic, partitionned by the keys. So that you recover the > keys in Flink. > > > > 2) Create a source for the stream of tuple your analysing -> output1 > (Tuples). > > > > 3) Create a KafkaSource, and parse/recover your key value pairs from this > source (e.g a first map operator) : map1 -> output 2 (K,V), then : > > > > > > > > a) If you need all key/Value pairs at each operator : > broadcast all partitions from the output 1 to the analysis operator > > > > b) if you dont need all key/values pairs, just chain > output1 to the analysis operator. Partitioning of K,V pairs will depend on > Kafka partitioning strategy, and can be controlled in Flink anyway. > > > > 4) The analysis operator : will perform a RichCoFlatMapFunction, and can > be Checkpointed. > > When receiving K,V pairs from output2, store them in a local state. > > When receiving tuple, should be able to to filter with the help of the > local state, and propagate downstream or not. > > > > > > > > > > > > > > > > > > > > > > > >> > Message du 30/05/16 13:41 >> > De : >> leon_mcl...@tutanota.com >> > A : "User" <>> user@flink.apache.org>> > >> > Copie à : >> > Objet : Elegantly sharing state in a streaming environment >> > >> >Hello Flink team, >> >> How can i partition and share static state among instances of a streaming >> operator? >> >> I have a huge list of keys and values, which are used to filter tuples in >> a stream. The list does not change. Currently i am sharing the list with >> each operator instance via the constructor, although only a subset of the >> list is required per operator (the assignment of subset to operator >> instance is known). I cannot use DataSet based functions in a streaming >> execution environment to assign sub lists. I also cannot use DataStream >> based partitioning functions as the list is static, i.e. not a DataStream. >> The dilemma exists as i am mixing static (DataSet type) content with >> streaming content. Is there any other approach aside from using an >> additional tool (e.g. distributed cache)? >> >> Thanks in advance. >> >> Regards >> Leon >> >> >> >>
