open-closed.swift

protocol AnalyticType {
    func track(_ event: String, parameters: [String: Any]?)
}

final class FacebookAnalytic: AnalyticType {
    
    func track(_ event: String, parameters: [String : Any]?) {
        // TODO: - Send facebook event
    }
    
}

final class GoogleAnalytic: AnalyticType {
    
    func track(_ event: String, parameters: [String : Any]?) {
        // TODO: - Send Google event
    }
    
}

final class AnalyticService: AnalyticType {
    
    let interactors: [AnalyticType]
    
    init(interactors: [AnalyticType]) {
        self.interactors = interactors
    }
    
    func track(_ event: String, parameters: [String : Any]? = nil) {
        interactors.forEach { $0.track(event, parameters: parameters) }
    }
    
}

let facebookInteractor = FacebookAnalytic()
let googleInteractor = GoogleAnalytic()
let analyticService = AnalyticService(interactors: [facebookInteractor, googleInteractor])

analyticService.track("Login")
analyticService.track("Post a story", parameters: ["title": "SOLID in swift"])