From f7b0981b7d2a02a89dd3ca569f9921e8e52f0b8e Mon Sep 17 00:00:00 2001
From: Hongbo Wu <hongbo@omnivore.app>
Date: Tue, 22 Nov 2022 12:12:12 +0800
Subject: [PATCH] Parse subscription filter in rules

---
 packages/rule-handler/package.json            |  3 +-
 .../{sendNotification.ts => notification.ts}  |  7 +-
 packages/rule-handler/src/rule.ts             | 74 +++++++++++++++----
 3 files changed, 63 insertions(+), 21 deletions(-)
 rename packages/rule-handler/src/{sendNotification.ts => notification.ts} (94%)

diff --git a/packages/rule-handler/package.json b/packages/rule-handler/package.json
index 6c17ca61b..41f80a65e 100644
--- a/packages/rule-handler/package.json
+++ b/packages/rule-handler/package.json
@@ -25,6 +25,7 @@
     "axios": "^0.27.2",
     "dotenv": "^16.0.1",
     "firebase-admin": "^10.0.2",
-    "jsonwebtoken": "^8.5.1"
+    "jsonwebtoken": "^8.5.1",
+    "search-query-parser": "^1.6.0"
   }
 }
diff --git a/packages/rule-handler/src/sendNotification.ts b/packages/rule-handler/src/notification.ts
similarity index 94%
rename from packages/rule-handler/src/sendNotification.ts
rename to packages/rule-handler/src/notification.ts
index c7cad5abc..31bfc20ca 100644
--- a/packages/rule-handler/src/sendNotification.ts
+++ b/packages/rule-handler/src/notification.ts
@@ -56,9 +56,9 @@ export const getDeviceTokens = async (
 }
 
 export const getBatchMessages = (
-  title: string,
   messages: string[],
   tokens: string[],
+  title?: string,
   imageUrl?: string
 ): Message[] => {
   const batchMessages: Message[] = []
@@ -93,8 +93,5 @@ export const sendMulticastPushNotifications = async (
 export const sendBatchPushNotifications = async (
   messages: Message[]
 ): Promise<BatchResponse | undefined> => {
-  const res = await getMessaging().sendAll(messages)
-  console.debug('res', res)
-
-  return res
+  return getMessaging().sendAll(messages)
 }
diff --git a/packages/rule-handler/src/rule.ts b/packages/rule-handler/src/rule.ts
index 2e57f1a88..990de516d 100644
--- a/packages/rule-handler/src/rule.ts
+++ b/packages/rule-handler/src/rule.ts
@@ -2,9 +2,10 @@ import {
   getBatchMessages,
   getDeviceTokens,
   sendBatchPushNotifications,
-} from './sendNotification'
+} from './notification'
 import { getAuthToken, PubSubData } from './index'
 import axios from 'axios'
+import { parse, SearchParserKeyWordOffset } from 'search-query-parser'
 
 export enum RuleActionType {
   AddLabel = 'ADD_LABEL',
@@ -30,6 +31,59 @@ export interface Rule {
   updatedAt: Date
 }
 
+interface SearchFilter {
+  subscriptionFilter?: string
+}
+
+const parseSearchFilter = (filter: string): SearchFilter => {
+  const searchFilter = filter ? filter.replace(/\W\s":/g, '') : undefined
+  const result: SearchFilter = {}
+
+  if (!searchFilter || searchFilter === '*') {
+    return result
+  }
+
+  const parsed = parse(searchFilter, {
+    keywords: ['subscription'],
+    tokenize: true,
+  })
+  if (parsed.offsets) {
+    const keywords = parsed.offsets
+      .filter((offset) => 'keyword' in offset)
+      .map((offset) => offset as SearchParserKeyWordOffset)
+
+    for (const keyword of keywords) {
+      switch (keyword.keyword) {
+        case 'subscription':
+          result.subscriptionFilter = keyword.value
+      }
+    }
+  }
+
+  return result
+}
+
+const isValidData = (filter: string, data: PubSubData): boolean => {
+  const searchFilter = parseSearchFilter(filter)
+
+  if (searchFilter.subscriptionFilter) {
+    return isValidSubscription(searchFilter.subscriptionFilter, data)
+  }
+
+  return true
+}
+
+const isValidSubscription = (
+  subscriptionFilter: string,
+  data: PubSubData
+): boolean => {
+  if (!data.subscription) {
+    return false
+  }
+
+  return subscriptionFilter === '*' || data.subscription === subscriptionFilter
+}
+
 export const getEnabledRules = async (
   userId: string,
   apiEndpoint: string,
@@ -77,9 +131,7 @@ export const triggerActions = async (
   jwtSecret: string
 ) => {
   for (const rule of rules) {
-    // TODO: filter out rules that don't match the trigger
-    if (!data.subscription) {
-      console.debug('no subscription')
+    if (!isValidData(rule.filter, data)) {
       continue
     }
 
@@ -94,14 +146,7 @@ export const triggerActions = async (
             console.log('No notification messages provided')
             continue
           }
-          await sendNotification(
-            userId,
-            data.subscription,
-            action.params,
-            apiEndpoint,
-            jwtSecret,
-            data.image
-          )
+          await sendNotification(userId, action.params, apiEndpoint, jwtSecret)
       }
     }
   }
@@ -109,20 +154,19 @@ export const triggerActions = async (
 
 export const sendNotification = async (
   userId: string,
-  subscription: string,
   messages: string[],
   apiEndpoint: string,
   jwtSecret: string,
+  title?: string,
   image?: string
 ) => {
-  const title = `📫 - ${subscription} has published a new article`
   // get device tokens by calling api
   const tokens = await getDeviceTokens(userId, apiEndpoint, jwtSecret)
 
   const batchMessages = getBatchMessages(
-    title,
     messages,
     tokens.map((t) => t.token),
+    title,
     image
   )