From 0dc8724fcb67c3d731fd7d993154c9db46c901e8 Mon Sep 17 00:00:00 2001
From: Hongbo Wu <hongbo@omnivore.app>
Date: Thu, 20 Apr 2023 16:31:06 +0800
Subject: [PATCH] Make pdf-handler subscribe to a pubsub notification for cloud
 storage

---
 packages/pdf-handler/package.json |   1 +
 packages/pdf-handler/src/index.ts | 123 ++++++++++++++++++------------
 2 files changed, 77 insertions(+), 47 deletions(-)

diff --git a/packages/pdf-handler/package.json b/packages/pdf-handler/package.json
index 7fa9b3c91..4e083bff5 100644
--- a/packages/pdf-handler/package.json
+++ b/packages/pdf-handler/package.json
@@ -29,6 +29,7 @@
     "@google-cloud/functions-framework": "3.1.2",
     "@google-cloud/pubsub": "^3.4.1",
     "@google-cloud/storage": "^5.18.1",
+    "@sentry/serverless": "^7.30.0",
     "axios": "^0.27.2",
     "concurrently": "^7.0.0",
     "pdfjs-dist": "^2.9.359"
diff --git a/packages/pdf-handler/src/index.ts b/packages/pdf-handler/src/index.ts
index 70783a1f3..efc2d11eb 100644
--- a/packages/pdf-handler/src/index.ts
+++ b/packages/pdf-handler/src/index.ts
@@ -1,11 +1,13 @@
-import {
-  EventFunction,
-  CloudFunctionsContext,
-} from '@google-cloud/functions-framework/build/src/functions'
-import { GetSignedUrlConfig, Storage } from '@google-cloud/storage'
 import { PubSub } from '@google-cloud/pubsub'
+import { GetSignedUrlConfig, Storage } from '@google-cloud/storage'
+import * as Sentry from '@sentry/serverless'
 import { parsePdf } from './pdf'
 
+Sentry.GCPFunction.init({
+  dsn: process.env.SENTRY_DSN,
+  tracesSampleRate: 0,
+})
+
 const pubsub = new PubSub()
 const storage = new Storage()
 const CONTENT_UPDATE_TOPIC = 'updatePageContent'
@@ -16,18 +18,16 @@ interface StorageEventData {
   contentType: string
 }
 
+function isStorageEventData(event: any): event is StorageEventData {
+  return 'name' in event && 'bucket' in event && 'contentType' in event
+}
+
 // Ensure this is a finalize event and that it is stored in the `u/` directory and is a PDF
-const shouldHandle = (data: StorageEventData, ctx: CloudFunctionsContext) => {
-  if (ctx.eventType !== 'google.storage.object.finalize') {
-    return false
-  }
-  if (
-    !data.name.startsWith('u/') ||
-    data.contentType.toLowerCase() != 'application/pdf'
-  ) {
-    return false
-  }
-  return true
+const shouldHandle = (data: StorageEventData) => {
+  return (
+    data.name.startsWith('u/') &&
+    data.contentType.toLowerCase() === 'application/pdf'
+  )
 }
 
 const getDocumentUrl = async (
@@ -69,37 +69,66 @@ export const updatePageContent = (
     })
 }
 
-export const pdfHandler: EventFunction = async (event, context) => {
-  const data = event as StorageEventData
-  const ctx = context as CloudFunctionsContext
-
-  if (shouldHandle(data, ctx)) {
-    console.log('handling pdf data', data)
-
-    const url = await getDocumentUrl(data)
-    console.log('PDF url: ', url)
-    if (!url) {
-      console.log('Could not fetch PDF', data.bucket, data.name)
-      return
+const getStorageEventData = (
+  pubSubMessage: string
+): StorageEventData | undefined => {
+  try {
+    const str = Buffer.from(pubSubMessage, 'base64').toString().trim()
+    const obj = JSON.parse(str) as unknown
+    if (isStorageEventData(obj)) {
+      return obj
     }
-
-    const parsed = await parsePdf(url)
-    const res = await updatePageContent(
-      data.name,
-      parsed.content,
-      parsed.title,
-      parsed.author,
-      parsed.description
-    )
-    console.log(
-      'publish result',
-      res,
-      'title',
-      parsed.title,
-      'author',
-      parsed.author
-    )
-  } else {
-    console.log('not handling pdf data', data)
+  } catch (err) {
+    console.log('error deserializing event: ', { pubSubMessage, err })
   }
+  return undefined
 }
+
+export const pdfHandler = Sentry.GCPFunction.wrapHttpFunction(
+  async (req, res) => {
+    /* eslint-disable @typescript-eslint/no-unsafe-member-access */
+    if ('message' in req.body && 'data' in req.body.message) {
+      const pubSubMessage = req.body.message.data as string
+      const data = getStorageEventData(pubSubMessage)
+      if (data) {
+        try {
+          if (shouldHandle(data)) {
+            console.log('handling pdf data', data)
+
+            const url = await getDocumentUrl(data)
+            console.log('PDF url: ', url)
+            if (!url) {
+              console.log('Could not fetch PDF', data.bucket, data.name)
+              return res.status(404).send('Could not fetch PDF')
+            }
+
+            const parsed = await parsePdf(url)
+            const result = await updatePageContent(
+              data.name,
+              parsed.content,
+              parsed.title,
+              parsed.author,
+              parsed.description
+            )
+            console.log(
+              'publish result',
+              result,
+              'title',
+              parsed.title,
+              'author',
+              parsed.author
+            )
+          } else {
+            console.log('not handling pdf data', data)
+          }
+        } catch (err) {
+          console.log('error handling event', { err, data })
+          return res.status(500).send('Error handling event')
+        }
+      }
+    } else {
+      console.log('no pubsub message')
+    }
+    res.send('ok')
+  }
+)