Runtime Utilities

/**
 * Utility for running JobGraphs on MiniCluster for testing
 */
public class JobGraphRunningUtil {
    
    /**
     * Execute JobGraph on MiniCluster and wait for completion
     * @param jobGraph JobGraph to execute
     * @param miniCluster MiniCluster instance for execution  
     * @throws Exception if job execution fails
     */
    public static void execute(JobGraph jobGraph, MiniCluster miniCluster) throws Exception;
    
    /**
     * Execute JobGraph with timeout
     * @param jobGraph JobGraph to execute
     * @param miniCluster MiniCluster instance
     * @param timeoutMs timeout in milliseconds
     * @return JobExecutionResult containing execution results
     * @throws Exception if execution fails or times out
     */
    public static JobExecutionResult executeWithTimeout(
        JobGraph jobGraph, 
        MiniCluster miniCluster, 
        long timeoutMs) throws Exception;
    
    /**
     * Execute JobGraph and return execution result
     * @param jobGraph JobGraph to execute
     * @param miniCluster MiniCluster instance
     * @return JobExecutionResult with job execution details
     * @throws Exception if execution fails
     */
    public static JobExecutionResult executeAndGetResult(
        JobGraph jobGraph, 
        MiniCluster miniCluster) throws Exception;
    
    /**
     * Execute multiple JobGraphs sequentially
     * @param jobGraphs list of JobGraphs to execute
     * @param miniCluster MiniCluster instance
     * @return List of JobExecutionResults
     * @throws Exception if any job execution fails
     */
    public static List<JobExecutionResult> executeSequentially(
        List<JobGraph> jobGraphs,
        MiniCluster miniCluster) throws Exception;
    
    /**
     * Submit JobGraph asynchronously and return CompletableFuture
     * @param jobGraph JobGraph to submit
     * @param miniCluster MiniCluster instance
     * @return CompletableFuture containing JobExecutionResult
     */
    public static CompletableFuture<JobExecutionResult> submitAsync(
        JobGraph jobGraph,
        MiniCluster miniCluster);
}

/**
 * Entry point for task executor process testing
 */
public class TaskExecutorProcessEntryPoint {
    
    /**
     * Main entry point for standalone task executor process
     * @param args command line arguments for task executor configuration
     */
    public static void main(String[] args);
    
    /**
     * Start task executor with specific configuration
     * @param config Configuration for task executor setup
     * @throws Exception if task executor startup fails
     */
    public static void startTaskExecutor(Configuration config) throws Exception;
    
    /**
     * Create default configuration for task executor testing
     * @return Configuration with testing defaults
     */
    public static Configuration createDefaultTestConfiguration();
}

/**
 * Tokenizer function for string processing tests
 */
public class Tokenizer implements FlatMapFunction<String, Tuple2<String, Integer>> {
    
    /**
     * Constructor for tokenizer with default configuration
     */
    public Tokenizer();
    
    /**
     * Constructor for tokenizer with custom delimiter
     * @param delimiter delimiter pattern for tokenization
     */
    public Tokenizer(String delimiter);
    
    @Override
    public void flatMap(String value, Collector<Tuple2<String, Integer>> out) throws Exception;
}

/**
 * Identity mapper for testing data flow without transformation
 */
public class NoOpIntMap implements MapFunction<Integer, Integer> {
    
    /**
     * Constructor for no-operation integer mapper
     */
    public NoOpIntMap();
    
    @Override
    public Integer map(Integer value) throws Exception;
}

/**
 * No-operation sink for testing data flow completion
 */
public class ReceiveCheckNoOpSink<T> implements SinkFunction<T> {
    
    /**
     * Constructor for no-op sink with receive tracking
     * @param expectedCount expected number of elements to receive
     */
    public ReceiveCheckNoOpSink(int expectedCount);
    
    @Override
    public void invoke(T value, Context context) throws Exception;
    
    /**
     * Check if expected number of elements were received
     * @return boolean indicating if expected count was reached
     */
    public boolean receivedExpectedCount();
    
    /**
     * Get actual count of received elements
     * @return int representing actual received count
     */
    public int getReceivedCount();
    
    /**
     * Reset the counter for reuse in multiple tests
     */
    public void reset();
}

/**
 * Utility class for recovery testing operations
 */
public class RecoveryTestUtils {
    
    /**
     * Validate recovery behavior from job execution result
     * @param result JobExecutionResult to analyze
     * @param expectedRestartCount expected number of restarts
     * @return boolean indicating if recovery behavior is valid
     */
    public static boolean validateRecoveryBehavior(
        JobExecutionResult result, 
        int expectedRestartCount);
    
    /**
     * Create configuration for failure injection testing
     * @param restartStrategy restart strategy to use
     * @param maxFailures maximum number of failures to inject
     * @return Configuration with failure injection settings
     */
    public static Configuration createFailureInjectionConfig(
        String restartStrategy,
        int maxFailures);
    
    /**
     * Wait for job to reach specific state with timeout
     * @param jobId JobID to monitor
     * @param targetState target JobStatus to wait for
     * @param timeoutMs timeout in milliseconds
     * @param restGateway RestClient for job monitoring
     * @return boolean indicating if state was reached
     * @throws Exception if monitoring fails
     */
    public static boolean waitForJobState(
        JobID jobId,
        JobStatus targetState,
        long timeoutMs,
        RestClusterClient<?> restGateway) throws Exception;
}

/**
 * Utility for creating and managing test environments
 */
public class TestEnvironmentUtil {
    
    /**
     * Create MiniCluster configuration for testing
     * @param parallelism desired parallelism
     * @param numTaskManagers number of task managers
     * @return Configuration for MiniCluster setup
     */
    public static Configuration createTestClusterConfig(
        int parallelism,
        int numTaskManagers);
    
    /**
     * Create streaming environment for testing
     * @param parallelism parallelism for the environment
     * @param checkpointingEnabled whether to enable checkpointing
     * @return StreamExecutionEnvironment configured for testing
     */
    public static StreamExecutionEnvironment createTestStreamEnv(
        int parallelism,
        boolean checkpointingEnabled);
    
    /**
     * Create batch environment for testing
     * @param parallelism parallelism for the environment
     * @return ExecutionEnvironment configured for testing
     */
    public static ExecutionEnvironment createTestBatchEnv(int parallelism);
    
    /**
     * Set up test-specific logging configuration
     * @param logLevel logging level for tests
     * @param logToConsole whether to log to console
     */
    public static void setupTestLogging(Level logLevel, boolean logToConsole);
    
    /**
     * Clean up test environment resources
     * @param environment execution environment to clean up
     * @param miniCluster mini cluster to shut down
     * @throws Exception if cleanup fails
     */
    public static void cleanupTestEnvironment(
        StreamExecutionEnvironment environment,
        MiniCluster miniCluster) throws Exception;
}

/**
 * Utility for metrics collection and validation in tests
 */
public class TestMetricsUtil {
    
    /**
     * Collect all metrics from MiniCluster
     * @param miniCluster cluster to collect metrics from
     * @return Map of metric names to values
     * @throws Exception if metrics collection fails
     */
    public static Map<String, Object> collectAllMetrics(MiniCluster miniCluster) throws Exception;
    
    /**
     * Wait for specific metric to reach expected value
     * @param miniCluster cluster to monitor
     * @param metricName name of metric to monitor
     * @param expectedValue expected metric value
     * @param timeoutMs timeout in milliseconds
     * @return boolean indicating if metric reached expected value
     * @throws Exception if monitoring fails
     */
    public static boolean waitForMetricValue(
        MiniCluster miniCluster,
        String metricName,
        Object expectedValue,
        long timeoutMs) throws Exception;
    
    /**
     * Validate job metrics against expected values
     * @param jobId JobID to validate metrics for
     * @param expectedMetrics map of expected metric values
     * @param miniCluster cluster to collect metrics from
     * @return boolean indicating if all metrics match expectations
     * @throws Exception if validation fails
     */
    public static boolean validateJobMetrics(
        JobID jobId,
        Map<String, Object> expectedMetrics,
        MiniCluster miniCluster) throws Exception;
}

import org.apache.flink.test.runtime.*;
import org.apache.flink.test.util.*;

// Example: Executing jobs with runtime utilities
public class JobExecutionTest {
    
    @Test
    public void testJobExecution() throws Exception {
        // Create test job graph
        JobGraph jobGraph = createTestJobGraph();
        
        // Set up mini cluster for testing
        Configuration config = TestEnvironmentUtil.createTestClusterConfig(4, 2);
        MiniCluster miniCluster = new MiniCluster(config);
        miniCluster.start();
        
        try {
            // Execute job with timeout
            JobExecutionResult result = JobGraphRunningUtil.executeWithTimeout(
                jobGraph, miniCluster, 30000L);
            
            // Validate execution results
            assertTrue(result.isSuccess());
            assertFalse(result.getAllAccumulatorResults().isEmpty());
            
        } finally {
            miniCluster.close();
        }
    }
    
    @Test
    public void testSequentialJobExecution() throws Exception {
        List<JobGraph> jobs = Arrays.asList(
            createTestJobGraph("job1"),
            createTestJobGraph("job2"),
            createTestJobGraph("job3")
        );
        
        Configuration config = TestEnvironmentUtil.createTestClusterConfig(2, 1);
        MiniCluster miniCluster = new MiniCluster(config);
        miniCluster.start();
        
        try {
            // Execute jobs sequentially
            List<JobExecutionResult> results = JobGraphRunningUtil.executeSequentially(
                jobs, miniCluster);
            
            // Validate all jobs completed successfully
            assertEquals(3, results.size());
            results.forEach(result -> assertTrue(result.isSuccess()));
            
        } finally {
            miniCluster.close();
        }
    }
}

// Example: Recovery testing with utilities
public class RecoveryUtilityTest {
    
    @Test
    public void testRecoveryBehavior() throws Exception {
        // Create job with failure injection
        JobGraph faultTolerantJob = createJobWithFailures();
        
        // Configure recovery settings
        Configuration config = RecoveryTestUtils.createFailureInjectionConfig(
            "fixed-delay", 3);
        config.setString("restart-strategy.fixed-delay.delay", "1s");
        
        MiniCluster miniCluster = new MiniCluster(config);
        miniCluster.start();
        
        try {
            // Execute job and wait for completion
            JobExecutionResult result = JobGraphRunningUtil.executeAndGetResult(
                faultTolerantJob, miniCluster);
            
            // Validate recovery behavior
            boolean recoveryValid = RecoveryTestUtils.validateRecoveryBehavior(
                result, 2);
            assertTrue(recoveryValid);
            
        } finally {
            miniCluster.close();
        }
    }
}

// Example: Using test functions
public class TestFunctionUsage {
    
    @Test
    public void testTokenizerFunction() throws Exception {
        StreamExecutionEnvironment env = TestEnvironmentUtil.createTestStreamEnv(1, false);
        
        // Create test data
        DataStreamSource<String> textStream = env.fromElements(
            "hello world", "test data", "apache flink"
        );
        
        // Apply tokenizer
        DataStream<Tuple2<String, Integer>> tokens = textStream
            .flatMap(new Tokenizer())
            .returns(TypeInformation.of(new TypeHint<Tuple2<String, Integer>>(){}));
        
        // Use no-op sink to count results
        ReceiveCheckNoOpSink<Tuple2<String, Integer>> countingSink = 
            new ReceiveCheckNoOpSink<>(6); // Expecting 6 tokens
        
        tokens.addSink(countingSink);
        
        // Execute and validate
        env.execute("Tokenizer Test");
        assertTrue(countingSink.receivedExpectedCount());
    }
}

// Example: Environment setup and cleanup
public class EnvironmentManagementTest {
    
    private StreamExecutionEnvironment env;
    private MiniCluster miniCluster;
    
    @Before
    public void setup() throws Exception {
        // Set up test logging
        TestEnvironmentUtil.setupTestLogging(Level.INFO, true);
        
        // Create test environment
        env = TestEnvironmentUtil.createTestStreamEnv(2, true);
        
        // Start mini cluster
        Configuration config = TestEnvironmentUtil.createTestClusterConfig(2, 1);
        miniCluster = new MiniCluster(config);
        miniCluster.start();
    }
    
    @After
    public void cleanup() throws Exception {
        // Clean up test resources
        TestEnvironmentUtil.cleanupTestEnvironment(env, miniCluster);
    }
    
    @Test
    public void testWithManagedEnvironment() throws Exception {
        // Test implementation using managed environment
        DataStreamSource<Integer> source = env.fromElements(1, 2, 3, 4, 5);
        
        DataStream<Integer> processed = source
            .map(new NoOpIntMap())
            .filter(x -> x > 2);
        
        ReceiveCheckNoOpSink<Integer> sink = new ReceiveCheckNoOpSink<>(3);
        processed.addSink(sink);
        
        env.execute("Managed Environment Test");
        assertTrue(sink.receivedExpectedCount());
    }
}