fix: Improve application opened event reliability (#165)

amplitude · May 15, 2024 · d3b9de7 · d3b9de7
1 parent 7777cdd
commit d3b9de7
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Showing 3 changed files with 59 additions and 36 deletions.
diff --git a/Sources/Amplitude/Plugins/iOS/IOSLifecycleMonitor.swift b/Sources/Amplitude/Plugins/iOS/IOSLifecycleMonitor.swift
@@ -17,7 +17,6 @@
             UIApplication.willEnterForegroundNotification,
             UIApplication.didFinishLaunchingNotification,
         ]
-        private var trackAppOpenedEventOnEnterForeground: Bool = true
         private var utils: DefaultEventUtils?
 
         override init() {
@@ -67,22 +66,35 @@
 
         func applicationWillEnterForeground(notification: NSNotification) {
             let timestamp = Int64(NSDate().timeIntervalSince1970 * 1000)
+
+            let fromBackground: Bool
+            if let sharedApplication = application {
+                switch sharedApplication.applicationState {
+                case .active, .inactive:
+                    fromBackground = false
+                case .background:
+                    fromBackground = true
+                @unknown default:
+                    fromBackground = false
+                }
+            } else {
+                fromBackground = false
+            }
+
             self.amplitude?.onEnterForeground(timestamp: timestamp)
-            if self.amplitude?.configuration.defaultTracking.appLifecycles == true && self.trackAppOpenedEventOnEnterForeground {
+            if self.amplitude?.configuration.defaultTracking.appLifecycles == true {
                 let info = Bundle.main.infoDictionary
                 let currentBuild = info?["CFBundleVersion"] as? String
                 let currentVersion = info?["CFBundleShortVersionString"] as? String
                 self.amplitude?.track(eventType: Constants.AMP_APPLICATION_OPENED_EVENT, eventProperties: [
                     Constants.AMP_APP_BUILD_PROPERTY: currentBuild ?? "",
                     Constants.AMP_APP_VERSION_PROPERTY: currentVersion ?? "",
-                    Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: true,
+                    Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: fromBackground,
                 ])
             }
         }
 
         func didEnterBackground(notification: NSNotification) {
-            self.trackAppOpenedEventOnEnterForeground = true
-
             let timestamp = Int64(NSDate().timeIntervalSince1970 * 1000)
             self.amplitude?.onExitForeground(timestamp: timestamp)
             if self.amplitude?.configuration.defaultTracking.appLifecycles == true {
@@ -91,8 +103,6 @@
         }
 
         func applicationDidFinishLaunchingNotification(notification: NSNotification) {
-            self.trackAppOpenedEventOnEnterForeground = false
-
             utils?.trackAppUpdatedInstalledEvent()
         }
     }

diff --git a/Sources/Amplitude/Utilities/DefaultEventUtils.swift b/Sources/Amplitude/Utilities/DefaultEventUtils.swift
@@ -29,11 +29,6 @@ public class DefaultEventUtils {
                     Constants.AMP_APP_PREVIOUS_VERSION_PROPERTY: previousVersion ?? "",
                 ])
             }
-            self.amplitude?.track(eventType: Constants.AMP_APPLICATION_OPENED_EVENT, eventProperties: [
-                Constants.AMP_APP_BUILD_PROPERTY: currentBuild ?? "",
-                Constants.AMP_APP_VERSION_PROPERTY: currentVersion ?? "",
-                Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: false,
-            ])
         }
 
         if currentBuild != previousBuild {

diff --git a/Tests/AmplitudeTests/AmplitudeIOSTests.swift b/Tests/AmplitudeTests/AmplitudeIOSTests.swift
@@ -36,18 +36,12 @@ final class AmplitudeIOSTests: XCTestCase {
         let currentVersion = info?["CFBundleShortVersionString"] ?? ""
 
         let events = storageMem.events()
-        XCTAssertEqual(events.count, 2)
+        XCTAssertEqual(events.count, 1)
         XCTAssertEqual(events[0].eventType, Constants.AMP_APPLICATION_INSTALLED_EVENT)
         XCTAssertEqual(getDictionary(events[0].eventProperties!), [
             Constants.AMP_APP_BUILD_PROPERTY: currentBuild,
             Constants.AMP_APP_VERSION_PROPERTY: currentVersion
         ])
-        XCTAssertEqual(events[1].eventType, Constants.AMP_APPLICATION_OPENED_EVENT)
-        XCTAssertEqual(getDictionary(events[1].eventProperties!), [
-            Constants.AMP_APP_BUILD_PROPERTY: currentBuild,
-            Constants.AMP_APP_VERSION_PROPERTY: currentVersion,
-            Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: false
-        ])
     }
 
     func testDidFinishLaunching_ApplicationUpdated() throws {
@@ -69,20 +63,14 @@ final class AmplitudeIOSTests: XCTestCase {
         let currentVersion = info?["CFBundleShortVersionString"] ?? ""
 
         let events = storageMem.events()
-        XCTAssertEqual(events.count, 2)
+        XCTAssertEqual(events.count, 1)
         XCTAssertEqual(events[0].eventType, Constants.AMP_APPLICATION_UPDATED_EVENT)
         XCTAssertEqual(getDictionary(events[0].eventProperties!), [
             Constants.AMP_APP_BUILD_PROPERTY: currentBuild,
             Constants.AMP_APP_VERSION_PROPERTY: currentVersion,
             Constants.AMP_APP_PREVIOUS_BUILD_PROPERTY: "abc",
             Constants.AMP_APP_PREVIOUS_VERSION_PROPERTY: "xyz"
         ])
-        XCTAssertEqual(events[1].eventType, Constants.AMP_APPLICATION_OPENED_EVENT)
-        XCTAssertEqual(getDictionary(events[1].eventProperties!), [
-            Constants.AMP_APP_BUILD_PROPERTY: currentBuild,
-            Constants.AMP_APP_VERSION_PROPERTY: currentVersion,
-            Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: false
-        ])
     }
 
     func testDidFinishLaunching_ApplicationOpened() throws {
@@ -105,16 +93,30 @@ final class AmplitudeIOSTests: XCTestCase {
         amplitude.waitForTrackingQueue()
 
         let events = storageMem.events()
-        XCTAssertEqual(events.count, 1)
-        XCTAssertEqual(events[0].eventType, Constants.AMP_APPLICATION_OPENED_EVENT)
-        XCTAssertEqual(getDictionary(events[0].eventProperties!), [
-            Constants.AMP_APP_BUILD_PROPERTY: currentBuild,
-            Constants.AMP_APP_VERSION_PROPERTY: currentVersion,
-            Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: false
-        ])
+        XCTAssertEqual(events.count, 0)
     }
 
-    func testWillEnterForeground() throws {
+    func testWillEnterForegroundFromBackground() throws {
+        class TestApplication {
+
+            static let sharedTest = TestApplication()
+
+            @objc class var shared: AnyObject {
+                return sharedTest
+            }
+
+            @objc var applicationState: UIApplication.State = .active
+        }
+
+        guard let originalMethod = class_getClassMethod(UIApplication.self, #selector(getter: UIApplication.shared)),
+              let testMethod = class_getClassMethod(TestApplication.self, #selector(getter: TestApplication.shared)) else {
+            XCTFail("Unable to find methods to swizzle")
+            return
+        }
+        let originalImplementation = method_getImplementation(originalMethod)
+        let testImplementation = method_getImplementation(testMethod)
+        method_setImplementation(originalMethod, testImplementation)
+
         let configuration = Configuration(
             apiKey: "api-key",
             storageProvider: storageMem,
@@ -127,17 +129,33 @@ final class AmplitudeIOSTests: XCTestCase {
         let currentVersion = info?["CFBundleShortVersionString"] ?? ""
 
         let amplitude = Amplitude(configuration: configuration)
+
+        TestApplication.sharedTest.applicationState = .inactive
+        NotificationCenter.default.post(name: UIApplication.willEnterForegroundNotification, object: nil)
+
+        TestApplication.sharedTest.applicationState = .background
         NotificationCenter.default.post(name: UIApplication.willEnterForegroundNotification, object: nil)
+
         amplitude.waitForTrackingQueue()
 
         let events = storageMem.events()
-        XCTAssertEqual(events.count, 1)
+        XCTAssertEqual(events.count, 2)
         XCTAssertEqual(events[0].eventType, Constants.AMP_APPLICATION_OPENED_EVENT)
         XCTAssertEqual(getDictionary(events[0].eventProperties!), [
             Constants.AMP_APP_BUILD_PROPERTY: currentBuild,
             Constants.AMP_APP_VERSION_PROPERTY: currentVersion,
-            Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: true
+            Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: false
+        ])
+
+        XCTAssertEqual(events[1].eventType, Constants.AMP_APPLICATION_OPENED_EVENT)
+        XCTAssertEqual(getDictionary(events[1].eventProperties!), [
+            Constants.AMP_APP_BUILD_PROPERTY: currentBuild,
+            Constants.AMP_APP_VERSION_PROPERTY: currentVersion,
+            Constants.AMP_APP_FROM_BACKGROUND_PROPERTY: false
         ])
+
+        // re-replace UIApplication.shared
+        method_setImplementation(originalMethod, originalImplementation)
     }
 
     func testDidEnterBackground() throws {