org.apache.flink.cep.PatternStream Java Examples

private void executeTest(String pattern, List<Event> data) throws Exception {

        StreamExecutionEnvironment streamExecutionEnvironment = StreamExecutionEnvironment.getExecutionEnvironment();

        DataStream<Event> eventDataStream = streamExecutionEnvironment.fromCollection(data);

        PatternStream<Event> patternStream = Dsl.compile(pattern, eventDataStream);

        patternStream.select(new PatternSelectFunction<Event, Event>() {
            private static final long serialVersionUID = 7242171752905668044L;

            @Override
            public Event select(Map<String, List<Event>> map) {
                results.putAll(map);
                return null;
            }
        });

        streamExecutionEnvironment.execute("test");
    }
 

static void executeTest(String pattern, List<Event> data) throws Exception {

        StreamExecutionEnvironment streamExecutionEnvironment = StreamExecutionEnvironment.getExecutionEnvironment();

        DataStream<Event> eventDataStream = streamExecutionEnvironment.fromCollection(data);

        PatternStream<Event> patternStream = Dsl.compile(pattern, eventDataStream);

        patternStream.select(new PatternSelectFunction<Event, Event>() {
            private static final long serialVersionUID = 7242171752905668044L;

            @Override
            public Event select(Map<String, List<Event>> map) {
                results.add(map);
                return null;
            }
        });

        streamExecutionEnvironment.execute("test");
    }
 

private static <TWarningType extends IWarning> DataStream<TWarningType> toWarningStream(DataStream<LocalWeatherData> localWeatherDataDataStream, IWarningPattern<LocalWeatherData, TWarningType> warningPattern) {
    PatternStream<LocalWeatherData> tempPatternStream = CEP.pattern(
            localWeatherDataDataStream.keyBy(new KeySelector<LocalWeatherData, String>() {
                @Override
                public String getKey(LocalWeatherData localWeatherData) throws Exception {
                    return localWeatherData.getStation().getWban();
                }
            }),
            warningPattern.getEventPattern());

    DataStream<TWarningType> warnings = tempPatternStream.select(new PatternSelectFunction<LocalWeatherData, TWarningType>() {
        @Override
        public TWarningType select(Map<String, List<LocalWeatherData>> map) throws Exception {
            return warningPattern.create(map);
        }
    }, new GenericTypeInfo<TWarningType>(warningPattern.getWarningTargetType()));

    return warnings;
}
 

private static <TWarningType extends IWarning> DataStream<TWarningType> toWarningStream(DataStream<LocalWeatherData> localWeatherDataDataStream, IWarningPattern<LocalWeatherData, TWarningType> warningPattern) {
    PatternStream<LocalWeatherData> tempPatternStream = CEP.pattern(
            localWeatherDataDataStream.keyBy(new KeySelector<LocalWeatherData, String>() {
                @Override
                public String getKey(LocalWeatherData localWeatherData) throws Exception {
                    return localWeatherData.getStation().getWban();
                }
            }),
            warningPattern.getEventPattern());

    DataStream<TWarningType> warnings = tempPatternStream.select(new PatternSelectFunction<LocalWeatherData, TWarningType>() {
        @Override
        public TWarningType select(Map<String, List<LocalWeatherData>> map) throws Exception {
            return warningPattern.create(map);
        }
    }, new GenericTypeInfo<TWarningType>(warningPattern.getWarningTargetType()));

    return warnings;
}
 

private static PatternStream<Event> compile(String expression, DataStream<Event> dataStream, boolean strictEventTypeMatching) {

        CaseInsensitiveInputStream inputStream = new CaseInsensitiveInputStream(expression);
        PatternLanguageLexer lexer = new PatternLanguageLexer(inputStream);

        CommonTokenStream tokens = new CommonTokenStream(lexer);
        PatternLanguageParser parser = new PatternLanguageParser(tokens);
        ParseTree parseTree = parser.patternExpression();

        ParseTreeWalker parseTreeWalker = new ParseTreeWalker();
        FlinkCepPatternLanguageListener listener = new FlinkCepPatternLanguageListener(strictEventTypeMatching);
        parseTreeWalker.walk(listener, parseTree);

        return CEP.pattern(dataStream, listener.getPattern());
    }
 

@Test
public void shouldEvaluateNextPattern() throws Exception {

    DataStream<Event> dataStream = null;
    PatternStream<Event> patternStream = Dsl.compile("A(attribute='testabc') B(attribute=30)", dataStream);

    assertThat(patternStream.getPattern(), is(notNullValue()));
    assertThat(patternStream.getPattern().getName(), is("B"));
    assertThat(patternStream.getPattern().getPrevious(), is(notNullValue()));
    assertThat(patternStream.getPattern().getPrevious().getName(), is("A"));
}
 

public static void main(String[] args) throws Exception {

		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
		env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime);
		env.setParallelism(1);

		DataStream<Event> eventStream = env.addSource(new OutOfOrderEventSource())
				.assignTimestampsAndWatermarks(new TimestampsAndWatermarks());

		Pattern<Event, ?> matchEverything =
				Pattern.<Event>begin("any")
						.where(new SimpleCondition<Event>() {
							@Override
							public boolean filter(Event event) throws Exception {
								return true;
							}
						});

		PatternStream<Event> patternStream = CEP.pattern(eventStream, matchEverything);
		OutputTag<Event> lateDataOutputTag = new OutputTag<Event>("late-events"){};

		SingleOutputStreamOperator<Event> sorted = patternStream
				.sideOutputLateData(lateDataOutputTag)
				.select(new PatternSelectFunction<Event, Event>() {
					@Override
					public Event select(Map<String, List<Event>> map) throws Exception {
						return map.get("any").get(0);
					}
				});

		sorted.print();
		sorted
				.getSideOutput(lateDataOutputTag)
				.map(e -> new Tuple2<>(e, "LATE"))
				.returns(Types.TUPLE(TypeInformation.of(Event.class), Types.STRING))
				.print();

		env.execute();
	}
 

public static void main(String[] args) throws Exception {

		ParameterTool params = ParameterTool.fromArgs(args);
		final String input = params.get("input", ExerciseBase.pathToRideData);

		final int servingSpeedFactor = 600; // events of 10 minutes are served in 1 second

		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
		env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime);
		env.setParallelism(ExerciseBase.parallelism);

		// CheckpointedTaxiRideSource delivers events in order
		DataStream<TaxiRide> rides = env.addSource(rideSourceOrTest(new CheckpointedTaxiRideSource(input, servingSpeedFactor)));

		DataStream<TaxiRide> keyedRides = rides
			.keyBy("rideId");

		// A complete taxi ride has a START event followed by an END event
		// This pattern is incomplete ...
		Pattern<TaxiRide, TaxiRide> completedRides = Pattern.<TaxiRide>begin("start");

		// We want to find rides that have NOT been completed within 120 minutes.
		// This pattern matches rides that ARE completed.
		// Below we will ignore rides that match this pattern, and emit those that timeout.
		PatternStream<TaxiRide> patternStream = CEP.pattern(keyedRides, completedRides.within(Time.minutes(120)));

		OutputTag<TaxiRide> timedout = new OutputTag<TaxiRide>("timedout"){};

		SingleOutputStreamOperator<TaxiRide> longRides = patternStream.flatSelect(
				timedout,
				new TaxiRideTimedOut<TaxiRide>(),
				new FlatSelectNothing<TaxiRide>()
		);

		printOrTest(longRides.getSideOutput(timedout));

		throw new MissingSolutionException();

//		env.execute("Long Taxi Rides (CEP)");
	}
 

public PatternStream<Event> compile(String expression, DataStream<Event> dataStream) {
    return Dsl.compile(expression, dataStream, strictEventTypeMatching);
}
 

/**
 * Returns a pattern stream based on a data stream and a pattern to search for
 * @param expression The expression representing the pattern which should be evaluated, refer to the projects documentation on syntax and features
 * @param dataStream The data stream which should be evaluated
 * @return The pattern stream providing the found patterns
 */
public static PatternStream<Event> compile(String expression, DataStream<Event> dataStream) {
    return Dsl.compile(expression, dataStream, false);
}