How to clear the DependencyValues?

[jaganrajj19]

Hello Guys,

I really need your suggestion here. So let's say I use ConfigDataSource as a dependency inside my SignInReducer.

import ComposableArchitecture
import Foundation

// MARK: - SessionDataSource Protocol
protocol ConfigDataSource {
    func storeConfig(_ user: User)
    func fetchConfig() -> User?
}

// MARK: - Concrete Implementation
struct ConfigDataSourceImpl: ConfigDataSource {
    func storeConfig(_ user: User) {

    }
    
    func fetchConfig() -> User? {
    }
}

// MARK: - DependencyKey
struct ConfigDataSourceDK: DependencyKey {
    static var cachedValue: ConfigDataSource?
    static func makeLiveValue() -> ConfigDataSource {
        SessionDataSourceImpl()
    }
}

// MARK: - DependencyValues Extension
extension DependencyValues {
    var configDataSource: ConfigDataSource {
        get { self[ConfigDataSourceDK.self] }
        set { self[ConfigDataSourceDK.self] = newValue }
    }
}

// MARK: - SignIn Reducer
struct SignInReducer: ReducerProtocol {
    struct State: Equatable {
        var username: String = ""
        var password: String = ""
        var loggedInUser: User? = nil
    }
    
    enum Action {
        case usernameChanged(String)
        case passwordChanged(String)
        case signInTapped
        case signedIn(User)
    }
    
    @Dependency(\.configDataSource) var configDataSource
    
    func reduce(into state: inout State, action: Action) -> EffectTask<Action> {
        
    }
}

When the user logs out of the app, I want to completely clear the configDataSource from the DependencyValues._current so that when the user logs in again, I can reinitialize with new config values.

Basically, my goal is to flush out the DepedencyValues completely and start as fresh.

I tried to use withDependencies and wrapped my root reducer as following when the user logs out.

func rebuildAppView() {
        if let child = appViewHoster {
            rlog(args: "Destroying previous AppViewHoster")
            child.willMove(toParent: nil)
            child.view.removeFromSuperview()
            child.removeFromParent()
            appViewHoster = nil
        }
        
        withDependencies {
            $0 = DependencyValues()
        } operation: { [weak self] in
            guard let self = self else { return }
            let store: StoreOf<AppReducer> = .init(
                initialState: .init(),
                reducer: AppReducer.init
            )
            let viewStore = ViewStore(store, observe: { $0 })
            viewStore.publisher.relaunch.sink { [weak self] relaunch in
                if relaunch {
                    rlog(args: "Relaunching AppView")
                    self?.rebuildAppView()
                }
            }.store(in: &cancellables)
            
            let appView = AppView(store: store)
                .environmentObject(appDelegate.theme)
            appViewHoster = self.hostView(appView)
        }
    }

However, it looks like my previous configDataSource never got deallocated. Pls assist. Thanks in advance!

[ryanmeisters]

I came here to ask a similar question. Our app resets a stack of "manager" dependencies whenever the session changes (log in/out).

We've started writing all new features in TCA and have made the manager dependencies available with @dependency, which is convenient.

However we need a way to reset the cached dependencies on log in/out.

Look through the Dependencies code I found

DependencyValues._current.resetCache()

However it requires @_spi(Beta) import Dependencies, and also it's marked as deprecated.

@mbrandonw what do you think about bringing that back? Or is there a different/recommended way to reset the cache? I think I saw in another thread that it was recommended for dependencies to manage resetting their own state, however that's not an option in our large legacy codebase (and seems error-prone anyway)