feat: add app exception event (#18)

Co-authored-by: xiaoweii <xiaoweii@amazom.com>

Author: zhu-xiaowei

Sources/Clickstream/Dependency/Clickstream/AutoRecord/AutoRecordEventClient.swift

@@ -28,6 +28,9 @@ class AutoRecordEventClient {
                 UIViewController.swizzle(viewDidAppear: onViewDidAppear)
             #endif
         }
+        if clickstream.configuration.isTrackAppExceptionEvents {
+            setupExceptionHandler()
+        }
     }
 
     func checkAppVersionUpdate(clickstream: ClickstreamContext) {
@@ -130,6 +133,26 @@ class AutoRecordEventClient {
         lastScreenStartTime = currentTimestamp
     }
 
+    func setupExceptionHandler() {
+        NSSetUncaughtExceptionHandler { exception in
+            AutoRecordEventClient.handleException(exception)
+        }
+    }
+
+    static func handleException(_ exception: NSException) {
+        let name = exception.name.rawValue
+        let reason = exception.reason ?? ""
+        let stackTrace = exception.callStackSymbols.joined(separator: "\n")
+        let attribute: ClickstreamAttribute = [
+            Event.ReservedAttribute.EXCEPTION_NAME: name,
+            Event.ReservedAttribute.EXCEPTION_REASON: reason,
+            Event.ReservedAttribute.EXCEPTION_STACK: stackTrace
+        ]
+        ClickstreamAnalytics.recordEvent(Event.PresetEvent.APP_EXCEPTION, attribute)
+        Thread.sleep(forTimeInterval: 0.2)
+        log.info("Recorded an app exception event, error name:\(name)")
+    }
+
     func recordEvent(_ event: ClickstreamEvent) {
         Task {
             try await clickstream.analyticsClient.record(event)
@@ -142,3 +165,5 @@ extension AutoRecordEventClient {
         static let minEngagementTime = 1_000
     }
 }
+
+extension AutoRecordEventClient: ClickstreamLogger {}

Sources/Clickstream/Dependency/Clickstream/ClickstreamContext.swift

@@ -42,7 +42,7 @@ extension UserDefaults: UserDefaultsBehaviour {
     /// Time interval after which the events are automatically submitted to server
     private let sendEventsInterval: Int
     /// Whether to track app exception events automatically
-    public var isTrackAppExceptionEvents: Bool
+    var isTrackAppExceptionEvents: Bool
     /// Whether to track app scren view events automatically
     public var isTrackScreenViewEvents: Bool
     /// Whether to compress events when send to server

Sources/Clickstream/Dependency/Clickstream/Event/ClickstreamEvent.swift

@@ -45,7 +45,7 @@ class ClickstreamEvent: AnalyticsPropertiesModel, Hashable {
 
     func addAttribute(_ attribute: AttributeValue, forKey key: String) {
         let eventError = Event.checkAttribute(currentNumber: attributes.count, key: key, value: attribute)
-        if eventError != nil {
+        if eventError != nil, key != Event.ReservedAttribute.EXCEPTION_STACK {
             attributes[eventError!.errorType] = eventError!.errorMessage
         } else {
             attributes[key] = attribute

Sources/Clickstream/Dependency/Clickstream/Event/Event.swift

@@ -167,6 +167,9 @@ enum Event {
         static let SCREEN_ID = "_screen_id"
         static let SCREEN_NAME = "_screen_name"
         static let IS_FIRST_TIME = "_is_first_time"
+        static let EXCEPTION_NAME = "_exception_name"
+        static let EXCEPTION_REASON = "_exception_reason"
+        static let EXCEPTION_STACK = "_excepiton_stack"
     }
 
     enum User {
@@ -209,6 +212,7 @@ enum Event {
         static let USER_ENGAGEMENT = "_user_engagement"
         static let SCREEN_VIEW = "_screen_view"
         static let APP_START = "_app_start"
+        static let APP_EXCEPTION = "_app_exception"
     }
 
     enum ErrorType {

Tests/ClickstreamTests/IntegrationTest.swift

@@ -308,6 +308,19 @@ class IntegrationTest: XCTestCase {
         XCTAssertEqual(1, eventCount)
     }
 
+    func testAppException() throws {
+        let exception = NSException(name: NSExceptionName("TestException"), reason: "Testing", userInfo: nil)
+        AutoRecordEventClient.handleException(exception)
+        Thread.sleep(forTimeInterval: 0.5)
+        let event = try eventRecorder.getBatchEvent().eventsJson.jsonArray()[0]
+        XCTAssertTrue(event["event_type"] as! String == Event.PresetEvent.APP_EXCEPTION)
+        let attributes = event["attributes"] as! [String: Any]
+        XCTAssertTrue(attributes[Event.ReservedAttribute.EXCEPTION_NAME] as! String == exception.name.rawValue)
+        XCTAssertTrue(attributes[Event.ReservedAttribute.EXCEPTION_REASON] as? String == exception.reason)
+        XCTAssertTrue(attributes[Event.ReservedAttribute.EXCEPTION_STACK] as! String
+            == exception.callStackSymbols.joined(separator: "\n"))
+    }
+
     private func getTestEvent() throws -> [String: Any] {
         var testEvent: [String: Any] = JsonObject()
         let eventArray = try eventRecorder.getBatchEvent().eventsJson.jsonArray()