[ 
https://issues.apache.org/jira/browse/FLINK-7169?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16119869#comment-16119869
 ] 

ASF GitHub Bot commented on FLINK-7169:
---------------------------------------

Github user dawidwys commented on a diff in the pull request:

    https://github.com/apache/flink/pull/4331#discussion_r132175179
  
    --- Diff: 
flink-libraries/flink-cep/src/test/java/org/apache/flink/cep/AfterMatchSkipITCase.java
 ---
    @@ -0,0 +1,431 @@
    +/*
    + * Licensed to the Apache Software Foundation (ASF) under one
    + * or more contributor license agreements.  See the NOTICE file
    + * distributed with this work for additional information
    + * regarding copyright ownership.  The ASF licenses this file
    + * to you under the Apache License, Version 2.0 (the
    + * "License"); you may not use this file except in compliance
    + * with the License.  You may obtain a copy of the License at
    + *
    + *     http://www.apache.org/licenses/LICENSE-2.0
    + *
    + * Unless required by applicable law or agreed to in writing, software
    + * distributed under the License is distributed on an "AS IS" BASIS,
    + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    + * See the License for the specific language governing permissions and
    + * limitations under the License.
    + */
    +
    +package org.apache.flink.cep;
    +
    +import org.apache.flink.cep.nfa.AfterMatchSkipStrategy;
    +import org.apache.flink.cep.pattern.MalformedPatternException;
    +import org.apache.flink.cep.pattern.Pattern;
    +import org.apache.flink.cep.pattern.conditions.SimpleCondition;
    +import org.apache.flink.core.fs.FileSystem;
    +import org.apache.flink.streaming.api.datastream.DataStream;
    +import 
org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
    +import org.apache.flink.streaming.util.StreamingMultipleProgramsTestBase;
    +
    +import org.junit.After;
    +import org.junit.Before;
    +import org.junit.Rule;
    +import org.junit.Test;
    +import org.junit.rules.TemporaryFolder;
    +
    +import java.util.List;
    +import java.util.Map;
    +
    +/**
    + * After match skip tests.
    + */
    +public class AfterMatchSkipITCase extends 
StreamingMultipleProgramsTestBase {
    +
    +   private String resultPath;
    +   private String expected;
    +
    +   private String lateEventPath;
    +   private String expectedLateEvents;
    +
    +   @Rule
    +   public TemporaryFolder tempFolder = new TemporaryFolder();
    +
    +   @Before
    +   public void before() throws Exception {
    +           resultPath = tempFolder.newFile().toURI().toString();
    +           expected = "";
    +
    +           lateEventPath = tempFolder.newFile().toURI().toString();
    +           expectedLateEvents = "";
    +   }
    +
    +   @After
    +   public void after() throws Exception {
    +           compareResultsByLinesInMemory(expected, resultPath);
    +           compareResultsByLinesInMemory(expectedLateEvents, 
lateEventPath);
    +   }
    +
    +   private PatternSelectFunction<Event, String> newIdSelectFunction(String 
... names) {
    +           return new PatternSelectFunction<Event, String>() {
    +
    +                   @Override
    +                   public String select(Map<String, List<Event>> pattern) {
    +                           StringBuilder builder = new StringBuilder();
    +                           for (String name: names) {
    +                                   for (Event e : pattern.get(name)) {
    +                                           
builder.append(e.getId()).append(",");
    +                                   }
    +                           }
    +                           return builder.toString();
    +                   }
    +           };
    +   }
    +
    +   @Test
    +   public void testSkipToNext() throws Exception {
    +           StreamExecutionEnvironment env = 
StreamExecutionEnvironment.getExecutionEnvironment();
    +
    +           DataStream<Event> input = env.fromElements(
    +                   new Event(1, "a", 0.0),
    +                   new Event(2, "a", 0.0),
    +                   new Event(3, "a", 0.0),
    +                   new Event(4, "a", 0.0),
    +                   new Event(5, "a", 0.0),
    +                   new Event(6, "a", 0.0)
    +           );
    +           Pattern<Event, ?> pattern = Pattern.<Event>begin("start",
    +                   new 
AfterMatchSkipStrategy(AfterMatchSkipStrategy.SkipStrategy.SKIP_TO_NEXT_EVENT))
    +                   .where(new SimpleCondition<Event>() {
    +
    +                   @Override
    +                   public boolean filter(Event value) throws Exception {
    +                           return value.getName().equals("a");
    +                   }
    +           }).times(3);
    +           DataStream<String> result = CEP.pattern(input, 
pattern).select(newIdSelectFunction("start"));
    +
    +           result.writeAsText(resultPath, FileSystem.WriteMode.OVERWRITE);
    +
    +           // expected sequence of matching event ids
    +           expected = "1,2,3,\n2,3,4,\n3,4,5,\n4,5,6,";
    +
    +           env.execute();
    +   }
    +
    +   @Test
    +   public void testSkipPastLast() throws Exception {
    +           StreamExecutionEnvironment env = 
StreamExecutionEnvironment.getExecutionEnvironment();
    +
    +           DataStream<Event> input = env.fromElements(
    +                   new Event(1, "a", 0.0),
    +                   new Event(2, "a", 0.0),
    +                   new Event(3, "a", 0.0),
    +                   new Event(4, "a", 0.0),
    +                   new Event(5, "a", 0.0),
    +                   new Event(6, "a", 0.0)
    +           );
    +           Pattern<Event, ?> pattern = Pattern.<Event>begin("start",
    +                   new 
AfterMatchSkipStrategy(AfterMatchSkipStrategy.SkipStrategy.SKIP_PAST_LAST_EVENT)).where(new
 SimpleCondition<Event>() {
    +
    +                   @Override
    +                   public boolean filter(Event value) throws Exception {
    +                           return value.getName().equals("a");
    +                   }
    +           }).times(3);
    +
    +           DataStream<String> result = CEP.pattern(input, 
pattern).select(newIdSelectFunction("start"));
    +
    +           result.writeAsText(resultPath, FileSystem.WriteMode.OVERWRITE);
    +
    +           // expected sequence of matching event ids
    +           expected = "1,2,3,\n4,5,6,";
    +
    +           env.execute();
    +   }
    +
    +   @Test
    +   public void testSkipToFirst() throws Exception {
    +           StreamExecutionEnvironment env = 
StreamExecutionEnvironment.getExecutionEnvironment();
    +
    +           DataStream<Event> input = env.fromElements(
    +                   new Event(1, "ab", 0.0),
    +                   new Event(2, "ab", 0.0),
    +                   new Event(3, "ab", 0.0),
    +                   new Event(4, "ab", 0.0),
    +                   new Event(5, "ab", 0.0),
    +                   new Event(6, "ab", 0.0),
    +                   new Event(7, "ab", 0.0)
    +           );
    +           Pattern<Event, ?> pattern = Pattern.<Event>begin("start",
    +                   new AfterMatchSkipStrategy(
    +                           
AfterMatchSkipStrategy.SkipStrategy.SKIP_TO_FIRST, "end"))
    +                   .where(new SimpleCondition<Event>() {
    +
    +                   @Override
    +                   public boolean filter(Event value) throws Exception {
    +                           return value.getName().contains("a");
    +                   }
    +           }).times(2).next("end").where(new SimpleCondition<Event>() {
    +
    +                   @Override
    +                   public boolean filter(Event value) throws Exception {
    +                           return value.getName().contains("b");
    +                   }
    +           }).times(2);
    +
    +           DataStream<String> result = CEP.pattern(input, 
pattern).select(newIdSelectFunction("start", "end"));
    +
    +           result.writeAsText(resultPath, FileSystem.WriteMode.OVERWRITE);
    +
    +           // expected sequence of matching event ids
    +           expected = "1,2,3,4,\n3,4,5,6,";
    +
    +           env.execute();
    +   }
    +
    +   @Test
    +   public void testSkipToLast() throws Exception {
    +           StreamExecutionEnvironment env = 
StreamExecutionEnvironment.getExecutionEnvironment();
    +
    +           DataStream<Event> input = env.fromElements(
    +                   new Event(1, "ab", 0.0),
    +                   new Event(2, "ab", 0.0),
    +                   new Event(3, "ab", 0.0),
    +                   new Event(4, "ab", 0.0),
    +                   new Event(5, "ab", 0.0),
    +                   new Event(6, "ab", 0.0),
    +                   new Event(7, "ab", 0.0)
    +           );
    +           Pattern<Event, ?> pattern = Pattern.<Event>begin("start", new 
AfterMatchSkipStrategy(
    +                   AfterMatchSkipStrategy.SkipStrategy.SKIP_TO_LAST, 
"end")).where(new SimpleCondition<Event>() {
    +
    +                   @Override
    +                   public boolean filter(Event value) throws Exception {
    +                           return value.getName().contains("a");
    +                   }
    +           }).times(2).next("end").where(new SimpleCondition<Event>() {
    +
    +                   @Override
    +                   public boolean filter(Event value) throws Exception {
    +                           return value.getName().contains("b");
    +                   }
    +           }).times(2);
    +           DataStream<String> result = CEP.pattern(input, 
pattern).select(newIdSelectFunction("start", "end"));
    +
    +           result.writeAsText(resultPath, FileSystem.WriteMode.OVERWRITE);
    +
    +           // expected sequence of matching event ids
    +           expected = "1,2,3,4,\n4,5,6,7,";
    +
    +           env.execute();
    +   }
    +
    +   @Test(expected = MalformedPatternException.class)
    --- End diff --
    
    Those tests should only test `NFACompiler` and thus be in `NFACompilerTest`.


> Support AFTER MATCH SKIP function in CEP library API
> ----------------------------------------------------
>
>                 Key: FLINK-7169
>                 URL: https://issues.apache.org/jira/browse/FLINK-7169
>             Project: Flink
>          Issue Type: Sub-task
>          Components: CEP
>            Reporter: Yueting Chen
>            Assignee: Yueting Chen
>             Fix For: 1.4.0
>
>
> In order to support Oracle's MATCH_RECOGNIZE on top of the CEP library, we 
> need to support AFTER MATCH SKIP function in CEP API.
> There're four options in AFTER MATCH SKIP, listed as follows:
> 1. AFTER MATCH SKIP TO NEXT ROW: resume pattern matching at the row after the 
> first row of the current match.
> 2. AFTER MATCH SKIP PAST LAST ROW: resume pattern matching at the next row 
> after the last row of the current match.
> 3. AFTER MATCH SKIP TO FIST *RPV*: resume pattern matching at the first row 
> that is mapped to the row pattern variable RPV.
> 4. AFTER MATCH SKIP TO LAST *RPV*: resume pattern matching at the last row 
> that is mapped to the row pattern variable RPV.
> I think we can introduce a new function to `CEP` class, which takes a new 
> parameter as AfterMatchSKipStrategy.
> The new API may looks like this
> {code}
> public static <T> PatternStream<T> pattern(DataStream<T> input, Pattern<T, ?> 
> pattern, AfterMatchSkipStrategy afterMatchSkipStrategy) 
> {code}
> We can also make `SKIP TO NEXT ROW` as the default option, because that's 
> what CEP library behaves currently.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

Reply via email to