From 08c4624fceb856cfa12c2836f38f2eb39384b75f Mon Sep 17 00:00:00 2001
From: Hongbo Wu <hongbo@omnivore.app>
Date: Thu, 4 Jan 2024 18:03:34 +0800
Subject: [PATCH] save the url in redis for 8 hours so rss-feeder will not try
 to re-save it

---
 packages/api/package.json              |  1 +
 packages/api/src/redis.ts              | 18 ++++++++++++++++++
 packages/api/src/server.ts             |  3 +++
 packages/api/src/services/save_page.ts |  9 +++++++++
 packages/api/src/util.ts               | 11 +++++++++++
 packages/rss-handler/src/index.ts      |  2 +-
 6 files changed, 43 insertions(+), 1 deletion(-)
 create mode 100644 packages/api/src/redis.ts

diff --git a/packages/api/package.json b/packages/api/package.json
index 34d9b24fb..75cecca83 100644
--- a/packages/api/package.json
+++ b/packages/api/package.json
@@ -82,6 +82,7 @@
     "pg": "^8.3.3",
     "postgrator": "^4.2.0",
     "private-ip": "^2.3.3",
+    "redis": "^4.3.1",
     "rss-parser": "^3.13.0",
     "sanitize-html": "^2.3.2",
     "sax": "^1.3.0",
diff --git a/packages/api/src/redis.ts b/packages/api/src/redis.ts
new file mode 100644
index 000000000..14559c0be
--- /dev/null
+++ b/packages/api/src/redis.ts
@@ -0,0 +1,18 @@
+import { createClient } from 'redis'
+import { env } from './env'
+
+export const redisClient = createClient({
+  url: env.redis.url,
+  socket: {
+    tls: env.redis.url?.startsWith('rediss://'), // rediss:// is the protocol for TLS
+    cert: env.redis.cert?.replace(/\\n/g, '\n'), // replace \n with new line
+    rejectUnauthorized: false, // for self-signed certs
+    connectTimeout: 10000, // 10 seconds
+    reconnectStrategy(retries: number): number | Error {
+      if (retries > 10) {
+        return new Error('Retries exhausted')
+      }
+      return 1000
+    },
+  },
+})
diff --git a/packages/api/src/server.ts b/packages/api/src/server.ts
index 1bb75a085..2380e3c37 100755
--- a/packages/api/src/server.ts
+++ b/packages/api/src/server.ts
@@ -15,6 +15,7 @@ import { config, loggers } from 'winston'
 import { makeApolloServer } from './apollo'
 import { appDataSource } from './data_source'
 import { env } from './env'
+import { redisClient } from './redis'
 import { articleRouter } from './routers/article_router'
 import { authRouter } from './routers/auth/auth_router'
 import { mobileAuthRouter } from './routers/auth/mobile/mobile_auth_router'
@@ -157,6 +158,8 @@ const main = async (): Promise<void> => {
   // as healthy.
   await appDataSource.initialize()
 
+  await redisClient.connect()
+
   const { app, apollo, httpServer } = createApp()
 
   await apollo.start()
diff --git a/packages/api/src/services/save_page.ts b/packages/api/src/services/save_page.ts
index 442dcea93..a49f9ac86 100644
--- a/packages/api/src/services/save_page.ts
+++ b/packages/api/src/services/save_page.ts
@@ -13,6 +13,7 @@ import {
   SavePageInput,
   SaveResult,
 } from '../generated/graphql'
+import { redisClient } from '../redis'
 import { authTrx } from '../repository'
 import { enqueueThumbnailTask } from '../utils/createTask'
 import {
@@ -194,6 +195,14 @@ export const savePage = async (
     }
   }
 
+  // save the url in redis for 8 hours so rss-feeder won't try to re-save it
+  const redisKey = `recent-saved-item:${user.id}:${itemToSave.originalUrl}`
+  const expireInSeconds = 60 * 60 * 8
+  await redisClient.set(redisKey, 1, {
+    EX: expireInSeconds,
+    NX: true,
+  })
+
   return {
     clientRequestId,
     url: `${homePageURL()}/${user.profile.username}/${slug}`,
diff --git a/packages/api/src/util.ts b/packages/api/src/util.ts
index c056d17cd..f37b51587 100755
--- a/packages/api/src/util.ts
+++ b/packages/api/src/util.ts
@@ -109,6 +109,10 @@ interface BackendEnv {
       max: number
     }
   }
+  redis: {
+    url?: string
+    cert?: string
+  }
 }
 
 /***
@@ -173,6 +177,8 @@ const nullableEnvVars = [
   'INTEGRATION_EXPORTER_URL',
   'INTEGRATION_IMPORTER_URL',
   'SUBSCRIPTION_FEED_MAX',
+  'REDIS_URL',
+  'REDIS_CERT',
 ] // Allow some vars to be null/empty
 
 /* If not in GAE and Prod/QA/Demo env (f.e. on localhost/dev env), allow following env vars to be null */
@@ -316,6 +322,10 @@ export function getEnv(): BackendEnv {
         : 256, // default to 256
     },
   }
+  const redis = {
+    url: parse('REDIS_URL'),
+    cert: parse('REDIS_CERT'),
+  }
 
   return {
     pg,
@@ -338,6 +348,7 @@ export function getEnv(): BackendEnv {
     gcp,
     pocket,
     subscription,
+    redis,
   }
 }
 
diff --git a/packages/rss-handler/src/index.ts b/packages/rss-handler/src/index.ts
index 2da93f3f7..4604690ef 100644
--- a/packages/rss-handler/src/index.ts
+++ b/packages/rss-handler/src/index.ts
@@ -224,7 +224,7 @@ const isItemRecentlySaved = async (
   userId: string,
   url: string
 ) => {
-  const key = `rss-recent-save:${userId}:${url}`
+  const key = `recent-saved-item:${userId}:${url}`
   const result = await redisClient.get(key)
   return !!result
 }