@Test
public void testSimplePatternWithSingleState() throws Exception {
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
DataStream<Tuple2<Integer, Integer>> input =
env.fromElements(new Tuple2<>(0, 1), new Tuple2<>(0, 2));
Pattern<Tuple2<Integer, Integer>, ?> pattern =
Pattern.<Tuple2<Integer, Integer>>begin("start")
.where(
new FilterFunction<Tuple2<Integer, Integer>>() {
@Override
public boolean filter(Tuple2<Integer, Integer> rec) throws Exception {
return rec.f1 == 1;
}
});
PatternStream<Tuple2<Integer, Integer>> pStream = CEP.pattern(input, pattern);
DataStream<Tuple2<Integer, Integer>> result =
pStream.select(
new PatternSelectFunction<Tuple2<Integer, Integer>, Tuple2<Integer, Integer>>() {
@Override
public Tuple2<Integer, Integer> select(Map<String, Tuple2<Integer, Integer>> pattern)
throws Exception {
return pattern.get("start");
}
});
result.writeAsText(resultPath, FileSystem.WriteMode.OVERWRITE);
expected = "(0,1)";
env.execute();
}
/**
* Checks that a certain event sequence is recognized
*
* @throws Exception
*/
@Test
public void testSimplePatternCEP() throws Exception {
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
DataStream<Event> input =
env.fromElements(
new Event(1, "barfoo", 1.0),
new Event(2, "start", 2.0),
new Event(3, "foobar", 3.0),
new SubEvent(4, "foo", 4.0, 1.0),
new Event(5, "middle", 5.0),
new SubEvent(6, "middle", 6.0, 2.0),
new SubEvent(7, "bar", 3.0, 3.0),
new Event(42, "42", 42.0),
new Event(8, "end", 1.0));
Pattern<Event, ?> pattern =
Pattern.<Event>begin("start")
.where(
new FilterFunction<Event>() {
@Override
public boolean filter(Event value) throws Exception {
return value.getName().equals("start");
}
})
.followedBy("middle")
.subtype(SubEvent.class)
.where(
new FilterFunction<SubEvent>() {
@Override
public boolean filter(SubEvent value) throws Exception {
return value.getName().equals("middle");
}
})
.followedBy("end")
.where(
new FilterFunction<Event>() {
@Override
public boolean filter(Event value) throws Exception {
return value.getName().equals("end");
}
});
DataStream<String> result =
CEP.pattern(input, pattern)
.select(
new PatternSelectFunction<Event, String>() {
@Override
public String select(Map<String, Event> pattern) {
StringBuilder builder = new StringBuilder();
builder
.append(pattern.get("start").getId())
.append(",")
.append(pattern.get("middle").getId())
.append(",")
.append(pattern.get("end").getId());
return builder.toString();
}
});
result.writeAsText(resultPath, FileSystem.WriteMode.OVERWRITE);
// expected sequence of matching event ids
expected = "2,6,8";
env.execute();
}
@Test
public void testSimpleKeyedPatternEventTime() throws Exception {
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime);
env.setParallelism(2);
// (Event, timestamp)
DataStream<Event> input =
env.fromElements(
Tuple2.of(new Event(1, "start", 1.0), 5L),
Tuple2.of(new Event(1, "middle", 2.0), 1L),
Tuple2.of(new Event(2, "middle", 2.0), 4L),
Tuple2.of(new Event(2, "start", 2.0), 3L),
Tuple2.of(new Event(1, "end", 3.0), 3L),
Tuple2.of(new Event(3, "start", 4.1), 5L),
Tuple2.of(new Event(1, "end", 4.0), 10L),
Tuple2.of(new Event(2, "end", 2.0), 8L),
Tuple2.of(new Event(1, "middle", 5.0), 7L),
Tuple2.of(new Event(3, "middle", 6.0), 9L),
Tuple2.of(new Event(3, "end", 7.0), 7L),
// last element for high final watermark
Tuple2.of(new Event(3, "end", 7.0), 100L))
.assignTimestampsAndWatermarks(
new AssignerWithPunctuatedWatermarks<Tuple2<Event, Long>>() {
@Override
public long extractTimestamp(Tuple2<Event, Long> element, long currentTimestamp) {
return element.f1;
}
@Override
public Watermark checkAndGetNextWatermark(
Tuple2<Event, Long> lastElement, long extractedTimestamp) {
return new Watermark(lastElement.f1 - 5);
}
})
.map(
new MapFunction<Tuple2<Event, Long>, Event>() {
@Override
public Event map(Tuple2<Event, Long> value) throws Exception {
return value.f0;
}
})
.keyBy(
new KeySelector<Event, Integer>() {
@Override
public Integer getKey(Event value) throws Exception {
return value.getId();
}
});
Pattern<Event, ?> pattern =
Pattern.<Event>begin("start")
.where(
new FilterFunction<Event>() {
@Override
public boolean filter(Event value) throws Exception {
return value.getName().equals("start");
}
})
.followedBy("middle")
.where(
new FilterFunction<Event>() {
@Override
public boolean filter(Event value) throws Exception {
return value.getName().equals("middle");
}
})
.followedBy("end")
.where(
new FilterFunction<Event>() {
@Override
public boolean filter(Event value) throws Exception {
return value.getName().equals("end");
}
});
DataStream<String> result =
CEP.pattern(input, pattern)
.select(
new PatternSelectFunction<Event, String>() {
@Override
public String select(Map<String, Event> pattern) {
StringBuilder builder = new StringBuilder();
builder
.append(pattern.get("start").getId())
.append(",")
.append(pattern.get("middle").getId())
.append(",")
.append(pattern.get("end").getId());
return builder.toString();
}
});
result.writeAsText(resultPath, FileSystem.WriteMode.OVERWRITE);
// the expected sequences of matching event ids
expected = "1,1,1\n2,2,2";
env.execute();
}
