Add reset method to MatomoTracker

MatomoTracker/MatomoTracker.swift

@@ -468,3 +468,24 @@ extension MatomoTracker {
     /// The version of the Matomo SDKs
     @objc public static let sdkVersion = "7.3"
 }
+
+extension MatomoTracker {
+    /// Resets all session, visitor and campaign information.
+    ///
+    /// Dispatches events before restting itself.
+    /// After calling this method this instance behaves like the app has been freshly installed.
+    public func reset() {
+        dispatch()
+
+        matomoUserDefaults.reset()
+
+        visitor = Visitor.current(in: matomoUserDefaults)
+        session = Session.current(in: matomoUserDefaults)
+        dimensions = []
+        customVariables = []
+        campaignName = nil
+        campaignKeyword = nil
+
+        startNewSession()
+    }
+}

MatomoTracker/MatomoUserDefaults.swift

@@ -99,6 +99,18 @@ internal struct MatomoUserDefaults {
             userDefaults.set(newValue, forKey: MatomoUserDefaults.Key.lastOrder)
         }
     }
+
+    func reset() {
+        userDefaults.removeObject(forKey: Key.totalNumberOfVisits)
+        userDefaults.removeObject(forKey: Key.currentVisitTimestamp)
+        userDefaults.removeObject(forKey: Key.previousVistsTimestamp)
+        userDefaults.removeObject(forKey: Key.firstVistsTimestamp)
+        userDefaults.removeObject(forKey: Key.clientID)
+        userDefaults.removeObject(forKey: Key.forcedVisitorID)
+        userDefaults.removeObject(forKey: Key.visitorUserID)
+        userDefaults.removeObject(forKey: Key.optOut)
+        userDefaults.removeObject(forKey: Key.lastOrder)
+    }
 }
 
 extension MatomoUserDefaults {

MatomoTrackerTests/TrackerSpec.swift

@@ -135,5 +135,80 @@ class TrackerSpec: QuickSpec {
                 expect(tracker2.forcedVisitorId) == "0123456789abcdef"
             }
         }
+        describe("reset") {
+            it("generates new visitor") {
+                var queuedEvents = [Event]()
+                let queue = QueueMock()
+                let tracker = MatomoTracker.fixture(queue: queue, dispatcher: DispatcherMock())
+                queue.enqueueEventsHandler = { events, _ in
+                    queuedEvents += events
+                }
+
+                tracker.track(view: ["spec_view"])
+                tracker.reset()
+                tracker.track(view: ["spec_view"])
+
+                expect(queuedEvents.count) == 2
+                expect(queuedEvents.first?.visitor.id).toNot(equal(queuedEvents.last?.visitor.id))
+            }
+            it("clears session information") {
+                var queuedEvent: Event? = nil
+                let queue = QueueMock()
+                let tracker = MatomoTracker.fixture(queue: queue, dispatcher: DispatcherMock())
+                queue.enqueueEventsHandler = { events, _ in
+                    queuedEvent = events.first
+                }
+
+                tracker.startNewSession()
+                tracker.reset()
+                tracker.track(view: ["spec_view"])
+
+                expect(queuedEvent?.session.sessionsCount) == 1
+            }
+            it("clears dimensions") {
+                var queuedEvent: Event? = nil
+                let queue = QueueMock()
+                let tracker = MatomoTracker.fixture(queue: queue, dispatcher: DispatcherMock())
+                queue.enqueueEventsHandler = { events, _ in
+                    queuedEvent = events.first
+                }
+
+                tracker.set(dimension: CustomDimension(index: 0, value: "fake-dimension"))
+                tracker.reset()
+                tracker.track(view: ["spec_view"])
+
+                expect(queuedEvent?.dimensions).to(beEmpty())
+            }
+            it("removes all custom variables") {
+                var queuedEvent: Event? = nil
+                let queue = QueueMock()
+                let tracker = MatomoTracker.fixture(queue: queue, dispatcher: DispatcherMock())
+                queue.enqueueEventsHandler = { events, _ in
+                    queuedEvent = events.first
+                }
+
+                tracker.set(customVariable: CustomVariable(index: 0, name: "fake-variable", value: "fake-value"))
+                tracker.reset()
+                tracker.track(view: ["spec_view"])
+
+                expect(queuedEvent?.customVariables).to(beEmpty())
+            }
+            it("clear campaigns") {
+                var queuedEvent: Event? = nil
+                let queue = QueueMock()
+                let tracker = MatomoTracker.fixture(queue: queue, dispatcher: DispatcherMock())
+                queue.enqueueEventsHandler = { events, _ in
+                    queuedEvent = events.first
+                }
+
+                tracker.trackCampaign(name: "fake-campaign", keyword: "fake-keyword")
+                tracker.reset()
+                tracker.track(view: ["spec_view"])
+
+                expect(queuedEvent).toNot(beNil())
+                expect(queuedEvent?.campaignName).to(beNil())
+                expect(queuedEvent?.campaignKeyword).to(beNil())
+            }
+        }
     }
 }