[ https://issues.apache.org/jira/browse/FLINK-4520?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15504300#comment-15504300 ]
ASF GitHub Bot commented on FLINK-4520: --------------------------------------- Github user StephanEwen commented on the issue: https://github.com/apache/flink/pull/2487 Thank you for that big contribution. Siddhi looks like a cool approach to CEP. Before digging into the details, I would like to start a discussion about whether we should have this as a part of the core Flink repository, as a subproject, or if it would be best to have it initially as an external project. The reason is that that Flink repository is becoming a bit big right now. Build times are very long, test stability hard to manage, and there is quite a bit of "dead" code that was contributed by someone at some point but seems rarely used and is not maintained by the contributors. To help have a good discussion, it would be great to learn a bit more: - How complete is the implementation? - Would you be up for maintaining this code? - Are you building this as an experiment, or building a production use case based on Siddhi on Flink? Thanks, Stephan > Integrate Siddhi as a lightweight CEP Library > --------------------------------------------- > > Key: FLINK-4520 > URL: https://issues.apache.org/jira/browse/FLINK-4520 > Project: Flink > Issue Type: New Feature > Components: CEP > Affects Versions: 1.2.0 > Reporter: Hao Chen > Labels: cep, library, patch-available > Fix For: 1.2.0 > > > h1. flink-siddhi proposal > h2. Abstraction > Siddhi CEP is a lightweight and easy-to-use Open Source Complex Event > Processing Engine (CEP) released as a Java Library under `Apache Software > License v2.0`. Siddhi CEP processes events which are generated by various > event sources, analyses them and notifies appropriate complex events > according to the user specified queries. > It would be very helpful for flink users (especially streaming application > developer) to provide a library to run Siddhi CEP query directly in Flink > streaming application. > * http://wso2.com/products/complex-event-processor/ > * https://github.com/wso2/siddhi > h2. Features > * Integrate Siddhi CEP as an stream operator (i.e. > `TupleStreamSiddhiOperator`), supporting rich CEP features like > * Filter > * Join > * Aggregation > * Group by > * Having > * Window > * Conditions and Expressions > * Pattern processing > * Sequence processing > * Event Tables > ... > * Provide easy-to-use Siddhi CEP API to integrate Flink DataStream API (See > `SiddhiCEP` and `SiddhiStream`) > * Register Flink DataStream associating native type information with > Siddhi Stream Schema, supporting POJO,Tuple, Primitive Type, etc. > * Connect with single or multiple Flink DataStreams with Siddhi CEP > Execution Plan > * Return output stream as DataStream with type intelligently inferred > from Siddhi Stream Schema > * Integrate siddhi runtime state management with Flink state (See > `AbstractSiddhiOperator`) > * Support siddhi plugin management to extend CEP functions. (See > `SiddhiCEP#registerExtension`) > h2. Test Cases > * org.apache.flink.contrib.siddhi.SiddhiCEPITCase: > https://github.com/haoch/flink/blob/FLINK-4520/flink-contrib/flink-siddhi/src/test/java/org/apache/flink/contrib/siddhi/SiddhiCEPITCase.java > h2. Example > {code} > StreamExecutionEnvironment env = > StreamExecutionEnvironment.getExecutionEnvironment(); > SiddhiCEP cep = SiddhiCEP.getSiddhiEnvironment(env); > cep.registerExtension("custom:plus",CustomPlusFunctionExtension.class); > cep.registerStream("inputStream1", input1, "id", "name", > "price","timestamp"); > cep.registerStream("inputStream2", input2, "id", "name", > "price","timestamp"); > DataStream<Tuple5<Integer,String,Integer,String,Double>> output = cep > .from("inputStream1").union("inputStream2") > .sql( > "from every s1 = inputStream1[id == 2] " > + " -> s2 = inputStream2[id == 3] " > + "select s1.id as id_1, s1.name as name_1, s2.id as id_2, s2.name as > name_2 , custom:plus(s1.price,s2.price) as price" > + "insert into outputStream" > ) > .returns("outputStream"); > env.execute(); > {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332)