[GA] add group join/leave event

cofacts · Jan 26, 2021 · 90ddb0a · 90ddb0a
1 parent 1f948f4
commit 90ddb0a
Showing 1 changed file with 29 additions and 4 deletions.
diff --git a/src/webhook/handlers/groupHandler.js b/src/webhook/handlers/groupHandler.js
@@ -9,6 +9,7 @@ import {
 } from './utils';
 import ga from 'src/lib/ga';
 import rollbar from 'src/lib/rollbar';
+import lineClient from 'src/webhook/lineClient';
 
 const SIMILARITY_THRESHOLD = 0.95;
 
@@ -23,12 +24,36 @@ export default async function({ req, type, replyToken, groupId, otherFields }) {
   };
 
   // Handle join/leave event
+  // To calculate total group bot joined, we set ga event value 1 as join, -1 as leave
+  // Details see Implicit Count in https://support.google.com/analytics/answer/1033068?hl=en
   if (type === 'join') {
-    //
-    return;
+    // https://developers.line.biz/en/reference/messaging-api/#get-members-group-count
+    // Note: leave group cannot get the number
+    const { count: numberOfGroupMembers } = await lineClient.get(
+      `/group/${groupId}/members/count`
+    );
+    console.log(
+      'Joined group, numberOfGroupMembers: ' +
+        JSON.stringify(numberOfGroupMembers)
+    );
+
+    const visitor = ga(groupId, 'N/A', '', otherFields.source.type);
+
+    visitor.event({
+      ec: 'Group',
+      ea: 'Join',
+      ev: 1,
+    });
+    visitor.set('cd2', numberOfGroupMembers);
+    visitor.send();
   } else if (type === 'leave') {
-    //
-    return;
+    const visitor = ga(groupId, 'N/A', '', otherFields.source.type);
+    visitor.event({
+      ec: 'Group',
+      ea: 'Leave',
+      ev: -1,
+    });
+    visitor.send();
   }
 
   // React to certain type of events