Use Combine for MongoController status changes

MongoView/MongoController.swift

@@ -9,6 +9,7 @@
 import Foundation
 import MongoSwift
 import NIO
+import Combine
 
 class MongoController {
     let connectionString: String
@@ -17,12 +18,7 @@ class MongoController {
     
     var client: MongoClient!
     
-    var status: Status = .connecting {
-        didSet {
-            statusDidChange.forEach { $0(status) }
-        }
-    }
-    var statusDidChange = [(Status) -> Void]()
+    @Published var status: ConnectionStatus = .connecting
 
     init(connectionString: String) {
         self.connectionString = connectionString
@@ -40,7 +36,7 @@ class MongoController {
         
         do {
             client = try MongoClient(connectionString, using: group)
-            status = .success
+            status = .connected
         } catch {
             status = .failed
             print("Failed to connect to Mongo: \(error)")
@@ -58,7 +54,7 @@ class MongoController {
 }
 
 extension MongoController {
-    enum Status {
-        case connecting, success, failed
+    enum ConnectionStatus {
+        case connecting, connected, failed
     }
 }

MongoView/Windows/DatabaseWindowController.swift

@@ -7,6 +7,7 @@
 //
 
 import Cocoa
+import Combine
 
 class DatabaseWindowController: NSWindowController {
 
@@ -21,6 +22,8 @@ class DatabaseWindowController: NSWindowController {
     
     private var databaseViewController: DatabaseViewController!
 
+    private var statusDidChangeHandler: Cancellable?
+    
     convenience init() {
         self.init(windowNibName: "DatabaseWindowController")
     }
@@ -32,17 +35,15 @@ class DatabaseWindowController: NSWindowController {
         if setupMongo {
             mongoController = MongoController(connectionString: "mongodb://localhost:27017")
         }
-        mongoController.statusDidChange.append({ [weak self] (status) in
-            guard let self = self else { return }
-            self.updateStatusText(status)
+        statusDidChangeHandler = mongoController.$status
+            .receive(on: DispatchQueue.main)
+            .sink { (status) in
+                self.updateStatusText(status)
     
-            if status == .success {
-                DispatchQueue.main.async {
+                if status == .connected {
                     self.initializeUI()
                 }
             }
-        })
-        self.updateStatusText(mongoController.status)
         if setupMongo {
             mongoController.setup()
         }
@@ -65,14 +66,14 @@ class DatabaseWindowController: NSWindowController {
         window?.title = databaseViewController?.title ?? "MongoView"
     }
     
-    private func updateStatusText(_ status: MongoController.Status) {
+    private func updateStatusText(_ status: MongoController.ConnectionStatus) {
         guard let statusView = self.statusView else { return }
         switch status {
         case .connecting:
             statusView.setText("Connecting...")
         case .failed:
             statusView.setText("Failed to connect")
-        case .success:
+        case .connected:
             statusView.setText("Connected to \(self.mongoController.connectionString)")
         }
     }