DependencyContainer

This micro-framework provides a dependency container that’s as simple as registering and resolving dependencies.

The project is inspired on Martin Fowler‘s article about Inversion of Control Containers and the Dependency Injection pattern.

I’ve also written a blog post about Applying Dependency Injection to Composable Routing for iOS Apps. Have a read at it too to see a sample app making use of the framework.

For a quick code sample look at the gist below:

import DependencyContainer

protocol APIClientInterface {
  func get() -> Data
}

class APIClient: APIClientInterface {
  func get() -> Data {
    ...
  }
}

protocol ViewModelInterface {
  func doSomething()
}

class ViewModel: ViewModelInterface {
  private let api: APIClientInterface

  init(api: APIClientInterface) {
    self.api = api
  }

  func doSomething() {
    ...
  }
}

// Create a container and register dependencies
let container = DependencyContainer()

container.register(APIClientInterface.self) { innerContainer in
  return APIClient()
}

// ViewModel depends on APIClient, so in its registration it's setup to
// resolve any inner dependency recursively
container.register(ViewModelInterface.self) { innerContainer in
  return ViewModel(api: innerContainer.resolve(APIClientInterface.self))
}

let viewModel = container.resolve(ViewModelInterface.self)
viewModel.doSomething()