Store view counts & last viewed time

functions/src/index.ts

@@ -15,6 +15,7 @@ export * from './create-answer'
 export * from './on-create-comment'
 export * from './on-fold-follow'
 export * from './on-fold-delete'
+export * from './on-view'
 export * from './unsubscribe'
 export * from './update-contract-metrics'
 export * from './update-user-metrics'

functions/src/on-view.ts

@@ -0,0 +1,24 @@
+import * as functions from 'firebase-functions'
+import * as admin from 'firebase-admin'
+import { View } from '../../common/tracking'
+
+const firestore = admin.firestore()
+
+export const onView = functions.firestore
+  .document('private-users/{userId}/views/{viewId}')
+  .onCreate(async (snapshot, context) => {
+    const { userId } = context.params
+
+    const { contractId, timestamp } = snapshot.data() as View
+
+    await firestore
+      .doc(`private-users/${userId}/cached/viewCounts`)
+      .set(
+        { [contractId]: admin.firestore.FieldValue.increment(1) },
+        { merge: true }
+      )
+
+    await firestore
+      .doc(`private-users/${userId}/cached/lastViewed`)
+      .set({ [contractId]: timestamp }, { merge: true })
+  })