Java Code Examples for org.apache.flink.runtime.checkpoint.Checkpoints#loadCheckpointMetadata()

public static Savepoint loadSavepoint(String checkpointPointer) {
	try {
		Method resolveCheckpointPointer = AbstractFsCheckpointStorage.class.getDeclaredMethod(
				"resolveCheckpointPointer",
				String.class);
		resolveCheckpointPointer.setAccessible(true);
		CompletedCheckpointStorageLocation loc = (CompletedCheckpointStorageLocation) resolveCheckpointPointer
				.invoke(null, checkpointPointer);

		return Checkpoints.loadCheckpointMetadata(new DataInputStream(loc.getMetadataHandle().openInputStream()),
				BravoTestPipeline.class.getClassLoader());
	} catch (Exception e) {
		throw new RuntimeException(e);
	}

}
 

/**
 * Load the Savepoint metadata object from the given path
 */
public static Savepoint loadSavepoint(String checkpointPointer) throws IOException {
	try {
		Method resolveCheckpointPointer = AbstractFsCheckpointStorage.class.getDeclaredMethod(
				"resolveCheckpointPointer",
				String.class);
		resolveCheckpointPointer.setAccessible(true);
		CompletedCheckpointStorageLocation loc = (CompletedCheckpointStorageLocation) resolveCheckpointPointer
				.invoke(null, checkpointPointer);

		return Checkpoints.loadCheckpointMetadata(new DataInputStream(loc.getMetadataHandle().openInputStream()),
				StateMetadataUtils.class.getClassLoader());
	} catch (Exception e) {
		throw new RuntimeException(e);
	}

}
 

public static void main(String[] args) throws IOException {
    //  读取元数据文件
    File f = new File("flink-learning-state/src/main/resources/_metadata");
    // 第二步，建立管道,FileInputStream文件输入流类用于读文件
    FileInputStream fis = new FileInputStream(f);
    BufferedInputStream bis = new BufferedInputStream(fis);
    DataInputStream dis = new DataInputStream(bis);

    // 通过 Flink 的 Checkpoints 类解析元数据文件
    Savepoint savepoint = Checkpoints.loadCheckpointMetadata(dis,
            MetadataSerializer.class.getClassLoader());
    // 打印当前的 CheckpointId
    System.out.println(savepoint.getCheckpointId());

    // 遍历 OperatorState，这里的每个 OperatorState 对应一个 Flink 任务的 Operator 算子
    // 不要与 OperatorState  和 KeyedState 混淆，不是一个层级的概念
    for (OperatorState operatorState : savepoint.getOperatorStates()) {
        System.out.println(operatorState);
        // 当前算子的状态大小为 0 ，表示算子不带状态，直接退出
        if (operatorState.getStateSize() == 0) {
            continue;
        }

        // 遍历当前算子的所有 subtask
        for (OperatorSubtaskState operatorSubtaskState : operatorState.getStates()) {
            // 解析 operatorSubtaskState 的 ManagedKeyedState
            parseManagedKeyedState(operatorSubtaskState);
            // 解析 operatorSubtaskState 的 ManagedOperatorState
            parseManagedOperatorState(operatorSubtaskState);
        }
    }
}
 

public static void main(String[] args) throws IOException {
    //  读取元数据文件
    File f = new File("flink-learning-state/src/main/resources/_metadata");
    // 第二步，建立管道,FileInputStream文件输入流类用于读文件
    FileInputStream fis = new FileInputStream(f);
    BufferedInputStream bis = new BufferedInputStream(fis);
    DataInputStream dis = new DataInputStream(bis);

    // 通过 Flink 的 Checkpoints 类解析元数据文件
    Savepoint savepoint = Checkpoints.loadCheckpointMetadata(dis,
            MetadataSerializer.class.getClassLoader());
    // 打印当前的 CheckpointId
    System.out.println(savepoint.getCheckpointId());

    // 遍历 OperatorState，这里的每个 OperatorState 对应一个 Flink 任务的 Operator 算子
    // 不要与 OperatorState  和 KeyedState 混淆，不是一个层级的概念
    for (OperatorState operatorState : savepoint.getOperatorStates()) {
        System.out.println(operatorState);
        // 当前算子的状态大小为 0 ，表示算子不带状态，直接退出
        if (operatorState.getStateSize() == 0) {
            continue;
        }

        // 遍历当前算子的所有 subtask
        for (OperatorSubtaskState operatorSubtaskState : operatorState.getStates()) {
            // 解析 operatorSubtaskState 的 ManagedKeyedState
            parseManagedKeyedState(operatorSubtaskState);
            // 解析 operatorSubtaskState 的 ManagedOperatorState
            parseManagedOperatorState(operatorSubtaskState);
        }
    }
}
 

/**
 * Takes the given string (representing a pointer to a checkpoint) and resolves it to a file
 * status for the checkpoint's metadata file.
 *
 *<p>This should only be used when the user code class loader is the current classloader for
 * the thread.
 * @param savepointPath The path to an external savepoint.
 * @return A state handle to savepoint's metadata.
 * @throws IOException Thrown, if the path cannot be resolved, the file system not accessed, or
 *     the path points to a location that does not seem to be a savepoint.
 */
public static Savepoint loadSavepoint(String savepointPath) throws IOException {
	CompletedCheckpointStorageLocation location = AbstractFsCheckpointStorage
		.resolveCheckpointPointer(savepointPath);

	try (DataInputStream stream = new DataInputStream(location.getMetadataHandle().openInputStream())) {
		return Checkpoints.loadCheckpointMetadata(stream, Thread.currentThread().getContextClassLoader());
	}
}
 

/**
 * Takes the given string (representing a pointer to a checkpoint) and resolves it to a file
 * status for the checkpoint's metadata file.
 *
 *<p>This should only be used when the user code class loader is the current classloader for
 * the thread.
 * @param savepointPath The path to an external savepoint.
 * @return A state handle to savepoint's metadata.
 * @throws IOException Thrown, if the path cannot be resolved, the file system not accessed, or
 *     the path points to a location that does not seem to be a savepoint.
 */
public static CheckpointMetadata loadSavepointMetadata(String savepointPath) throws IOException {
	CompletedCheckpointStorageLocation location = AbstractFsCheckpointStorage
		.resolveCheckpointPointer(savepointPath);

	try (DataInputStream stream = new DataInputStream(location.getMetadataHandle().openInputStream())) {
		return Checkpoints.loadCheckpointMetadata(stream, Thread.currentThread().getContextClassLoader(), savepointPath);
	}
}