org.apache.ignite.maintenance

## Interface MaintenanceWorkflowCallback

-     public interface MaintenanceWorkflowCallback

  Abstraction to decouple interaction between `MaintenanceRegistry` and components that may require maintenance. If a component may cause node to enter maintenance mode, it should register this callback in `MaintenanceRegistry` using method `MaintenanceRegistry.registerWorkflowCallback(String, MaintenanceWorkflowCallback)` `MaintenanceRegistry` during its workflow will collect necessary information about maintenance for components without knowing implementation details of the components.

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method and Description
    --- | ---
    `@NotNull List<MaintenanceAction<?>>` | `allActions()` Supplies list of `MaintenanceAction`s that user can call to fix maintenance situation for the component or get information about ongoing actions.
    `@Nullable MaintenanceAction<?>` | `automaticAction()` Component can provide optional `MaintenanceAction` that will be executed automatically by `MaintenanceRegistry` when node enters maintenance mode.
    `boolean` | `shouldProceedWithMaintenance()` Called by `MaintenanceRegistry` and enables it to check if maintenance is still needed for component that provided this callback.

- - ### Method Detail

    - #### shouldProceedWithMaintenance

          boolean shouldProceedWithMaintenance()

      Called by `MaintenanceRegistry` and enables it to check if maintenance is still needed for component that provided this callback. User may fix maintenance situation by hand when node was down thus before going to maintenance mode we should be able to check if it is still necessary.
      Returns:
        `True` if maintenance is still needed for the component.

    - #### allActions

          @NotNull
          @NotNull List<MaintenanceAction<?>> allActions()

      Supplies list of `MaintenanceAction`s that user can call to fix maintenance situation for the component or get information about ongoing actions. Should not be null or empty.
      Returns:
        Not null and non-empty `List` of `MaintenanceAction`.

    - #### automaticAction

          @Nullable
          @Nullable MaintenanceAction<?> automaticAction()

      Component can provide optional `MaintenanceAction` that will be executed automatically by `MaintenanceRegistry` when node enters maintenance mode. If no automatic actions are provided `MaintenanceRegistry` will wait for user to trigger `MaintenanceAction` with logic to fix the maintenance situation.
      Returns:
        `MaintenanceAction` for automatic execution or null if maintenance situation should not be fixed automatically.

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Ignite Database and Caching Platform | : ver. 2.11.0
Release Date | : September 11 2021