Protocol for common ReSwift middleware usecase

MiddlewareProcessor.swift

import ReSwift

public protocol MiddlewareProcessor {
    typealias GetStateFunction = () -> Any?
    func preprocess(dispatch: DispatchFunction, action: Action, getState: GetStateFunction)
    func postprocess(dispatch: DispatchFunction, action: Action, getState: GetStateFunction)
}

public extension MiddlewareProcessor {
    
    func preprocess(dispatch: DispatchFunction, action: Action, getState: GetStateFunction)  {}
    
    func postprocess(dispatch: DispatchFunction, action: Action, getState: GetStateFunction) {}
    
    func middleware() -> Middleware<Any> {
        return { dispatch, getState in
            return { next in
                return { action in
                    self.preprocess(dispatch: dispatch, action: action, getState: getState)
                    next(action)
                    self.postprocess(dispatch: dispatch, action: action, getState: getState)
                }
            }
        }
    }
    
}