flink StreamGraph 构造flink任务

背景

通常使用flink 提供的高级算子来编写flink 任务，对底层不是很了解，尤其是如何生成作业图的细节
下面通过构造一个有向无环图，来实际看一下

主要步骤

1.增加source
2.增加operator
3. 增加一条边，连接source和operator
4. 增加sink
5. 增加一条边，连接operator和sink

代码

 // Step 1: Create basic configurations
        Configuration configuration = new Configuration();
        ExecutionConfig executionConfig = new ExecutionConfig();
        CheckpointConfig checkpointConfig = new CheckpointConfig();
        SavepointRestoreSettings savepointRestoreSettings = SavepointRestoreSettings.none();

        // Step 2: Create a new StreamGraph instance
        StreamGraph streamGraph = new StreamGraph(configuration, executionConfig, checkpointConfig, savepointRestoreSettings);

        // Step 3: Add a source operator

        GeneratorFunction<Long, String> generatorFunction = index -> "Number: " + index;
        DataGeneratorSource<String> source = new DataGeneratorSource<>(generatorFunction, Long.MAX_VALUE, RateLimiterStrategy.perSecond(1), Types.STRING);
        SourceOperatorFactory<String> sourceOperatorFactory = new SourceOperatorFactory<>(source, WatermarkStrategy.noWatermarks());
        streamGraph.addSource(1, "sourceNode", "sourceDescription", sourceOperatorFactory, TypeInformation.of(String.class), TypeInformation.of(String.class), "sourceSlot");

        // Step 4: Add a map operator to transform the data
        StreamMap<String, String> mapOperator = new StreamMap<>(new MapFunction<String, String>() {
            @Override
            public String map(String value) throws Exception {
                return value;
            }
        });
        SimpleOperatorFactory<String> mapOperatorFactory = SimpleOperatorFactory.of(mapOperator);
        streamGraph.addOperator(2, "mapNode", "mapDescription", mapOperatorFactory, TypeInformation.of(String.class), TypeInformation.of(String.class), "mapSlot");

        // Step 5: Connect source and map operator
        streamGraph.addEdge(1, 2, 0);

        // Step 6: Add a sink operator to consume the data
        StreamMap<String, String> sinkOperator = new StreamMap<>(new MapFunction<String, String>() {
            @Override
            public String map(String value) throws Exception {
                System.out.println(value);
                return value;
            }
        });
        SimpleOperatorFactory<String> sinkOperatorFactory = SimpleOperatorFactory.of(sinkOperator);
        streamGraph.addSink(3, "sinkNode", "sinkDescription", sinkOperatorFactory, TypeInformation.of(String.class), TypeInformation.of(String.class), "sinkSlot");

        // Step 7: Connect map and sink operator
        streamGraph.addEdge(2, 3, 0);
        streamGraph.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);
        streamGraph.setMaxParallelism(1,1);
        streamGraph.setMaxParallelism(2,1);
        streamGraph.setMaxParallelism(3,1);
        streamGraph.setGlobalStreamExchangeMode(GlobalStreamExchangeMode.ALL_EDGES_PIPELINED);


        // Step 8: Convert StreamGraph to JobGraph
        JobGraph jobGraph = streamGraph.getJobGraph();


        // Step 9: Set up a MiniCluster for local execution
        MiniClusterConfiguration miniClusterConfig = new MiniClusterConfiguration.Builder()
                .setNumTaskManagers(10)
                .setNumSlotsPerTaskManager(10)
                .build();
        MiniCluster miniCluster = new MiniCluster(miniClusterConfig);

        // Step 10: Start the MiniCluster
        miniCluster.start();

        // Step 11: Submit the job to the MiniCluster
        JobExecutionResult result = miniCluster.executeJobBlocking(jobGraph);
        System.out.println("Job completed with result: " + result);

        // Step 12: Stop the MiniCluster
        miniCluster.close();