refactor: for session_id

packages/plugins/plugin-amplitudeSession/src/AmplitudeSessionPlugin.tsx

@@ -10,30 +10,48 @@ import {
   GroupEventType,
   UpdateType,
   AliasEventType,
+  SegmentClient,
 } from '@segment/analytics-react-native';
 
+import AsyncStorage from '@react-native-async-storage/async-storage';
+import { AppState } from 'react-native';
+
 const MAX_SESSION_TIME_IN_MS = 300000;
+const SESSION_ID_KEY = 'previous_session_id';
+const LAST_EVENT_TIME_KEY = 'last_event_time';
+const AMP_SESSION_START_EVENT = 'session_start';
+const AMP_SESSION_END_EVENT = 'session_end';
+
 export class AmplitudeSessionPlugin extends EventPlugin {
   type = PluginType.enrichment;
   key = 'Actions Amplitude';
   active = false;
-  sessionId: number | undefined;
-  sessionTimer: ReturnType<typeof setTimeout> | undefined;
-
-  update(settings: SegmentAPISettings, _: UpdateType) {
-    const integrations = settings.integrations;
-    if (this.key in integrations) {
-      this.active = true;
-      this.refreshSession();
+  sessionId = -1;
+  lastEventTime = -1;
+
+  configure = async (analytics: SegmentClient): Promise<void> => {
+    this.analytics = analytics;
+    await this.loadSessionData();
+    AppState.addEventListener('change', this.handleAppStateChange);
+  };
+
+  update(settings: SegmentAPISettings, type: UpdateType) {
+    if (type !== UpdateType.initial) {
+      return;
     }
+    this.active = settings.integrations?.hasOwnProperty(this.key) ?? false;
   }
 
-  execute(event: SegmentEvent) {
+  async execute(event: SegmentEvent) {
     if (!this.active) {
       return event;
     }
 
-    this.refreshSession();
+    if (this.sessionId === -1 || this.lastEventTime === -1) {
+      await this.loadSessionData();
+    }
+
+    await this.startNewSessionIfNecessary();
 
     let result = event;
     switch (result.type) {
@@ -53,6 +71,10 @@ export class AmplitudeSessionPlugin extends EventPlugin {
         result = this.group(result);
         break;
     }
+
+    this.lastEventTime = Date.now();
+    await this.saveSessionData();
+
     return result;
   }
 
@@ -65,6 +87,10 @@ export class AmplitudeSessionPlugin extends EventPlugin {
   }
 
   screen(event: ScreenEventType) {
+    event.properties = {
+      ...event.properties,
+      name: event.name,
+    };
     return this.insertSession(event) as ScreenEventType;
   }
 
@@ -76,39 +102,105 @@ export class AmplitudeSessionPlugin extends EventPlugin {
     return this.insertSession(event) as AliasEventType;
   }
 
-  reset() {
-    this.resetSession();
+  async reset() {
+    this.sessionId = -1;
+    this.lastEventTime = -1;
+    await AsyncStorage.removeItem(SESSION_ID_KEY);
+    await AsyncStorage.removeItem(LAST_EVENT_TIME_KEY);
   }
 
   private insertSession = (event: SegmentEvent) => {
-    const returnEvent = event;
-    const integrations = event.integrations;
-    returnEvent.integrations = {
-      ...integrations,
-      [this.key]: {
-        session_id: this.sessionId,
+    const integrations = event.integrations || {};
+    const existingIntegration = integrations[this.key];
+    const hasSessionId =
+      typeof existingIntegration === 'object' &&
+      existingIntegration !== null &&
+      'session_id' in existingIntegration;
+
+    if (hasSessionId) {
+      return event;
+    }
+
+    return {
+      ...event,
+      integrations: {
+        ...integrations,
+        [this.key]: { session_id: this.sessionId },
       },
     };
-    return returnEvent;
   };
 
-  private resetSession = () => {
-    this.sessionId = Date.now();
-    this.sessionTimer = undefined;
+  private onBackground = () => {
+    this.lastEventTime = Date.now();
+    this.saveSessionData();
+  };
+
+  private onForeground = () => {
+    this.startNewSessionIfNecessary();
   };
 
-  private refreshSession = () => {
-    if (this.sessionId === undefined) {
-      this.sessionId = Date.now();
+  private async startNewSessionIfNecessary() {
+    const current = Date.now();
+
+    const sessionExpired =
+      this.sessionId === -1 ||
+      this.lastEventTime === -1 ||
+      current - this.lastEventTime >= MAX_SESSION_TIME_IN_MS;
+
+    // Avoid loop: if session just started recently, skip restarting
+    if (!sessionExpired || current - this.sessionId < 1000) {
+      return;
     }
 
-    if (this.sessionTimer !== undefined) {
-      clearTimeout(this.sessionTimer);
+    await this.endSession();
+    await this.startNewSession();
+  }
+
+  private async startNewSession() {
+    this.sessionId = Date.now();
+    this.lastEventTime = this.sessionId;
+    await this.saveSessionData();
+
+    this.analytics?.track(AMP_SESSION_START_EVENT, {
+      integrations: {
+        [this.key]: { session_id: this.sessionId },
+      },
+    });
+  }
+
+  private async endSession() {
+    if (this.sessionId === -1) {
+      return;
     }
 
-    this.sessionTimer = setTimeout(
-      () => this.resetSession(),
-      MAX_SESSION_TIME_IN_MS
+    this.analytics?.track(AMP_SESSION_END_EVENT, {
+      integrations: {
+        [this.key]: { session_id: this.sessionId },
+      },
+    });
+  }
+
+  private async loadSessionData() {
+    const storedSessionId = await AsyncStorage.getItem(SESSION_ID_KEY);
+    const storedLastEventTime = await AsyncStorage.getItem(LAST_EVENT_TIME_KEY);
+    this.sessionId = storedSessionId != null ? Number(storedSessionId) : -1;
+    this.lastEventTime =
+      storedLastEventTime != null ? Number(storedLastEventTime) : -1;
+  }
+
+  private async saveSessionData() {
+    await AsyncStorage.setItem(SESSION_ID_KEY, this.sessionId.toString());
+    await AsyncStorage.setItem(
+      LAST_EVENT_TIME_KEY,
+      this.lastEventTime.toString()
     );
+  }
+
+  private handleAppStateChange = (nextAppState: string) => {
+    if (nextAppState === 'active') {
+      this.onForeground();
+    } else if (nextAppState === 'background') {
+      this.onBackground();
+    }
   };
 }