db backup function

functions/package.json

@@ -11,14 +11,14 @@
   },
   "main": "lib/index.js",
   "dependencies": {
+    "axios": "^0.18.0",
     "body-parser": "^1.18.3",
     "cors": "^2.8.5",
     "express": "^4.16.4",
     "firebase-admin": "~6.0.0",
     "firebase-functions": "^2.1.0",
     "google-auth-library": "^2.0.1",
-    "googleapis": "^35.0.0",
-    "request-promise": "^4.2.2"
+    "googleapis": "^35.0.0"
   },
   "devDependencies": {
     "tslint": "~5.8.0",

functions/src/databaseBackup.ts

@@ -1,12 +1,14 @@
-import { pubsub } from 'firebase-functions'
+// import { pubsub } from 'firebase-functions'
 import { JWT } from 'google-auth-library'
-import * as admin from 'firebase-admin'
 // import * as rp from 'request-promise'
-import * as devKey from './config/dev-service-account-key.json'
+import * as config from './config/dev-service-account-key.json'
+import Axios from 'axios'
 
-const PROJECT_ID = 'test'
+/*  Cloud function to automatically backup the firebase database adapted from: 
+    https://thatweirddeveloper.com/how-to-back-up-cloud-firestore-periodically
+*/
 
-admin.initializeApp()
+const PROJECT_ID = config.project_id
 
 // authorise application using JWT, requires key file defined above as dev key
 // see config/readme for more info
@@ -16,17 +18,15 @@ const getAccessToken = async () => {
     'https://www.googleapis.com/auth/cloud-platform',
   ]
   const jwtClient = new JWT(
-    devKey.client_email,
+    config.client_email,
     null,
-    devKey.private_key,
+    config.private_key,
     scopes,
   )
   try {
     const authorization = await jwtClient.authorize()
-    console.log('authorisation successful', authorization)
     return authorization.access_token
   } catch (error) {
-    console.error(error)
     return null
   }
 }
@@ -36,19 +36,35 @@ export const AuthTest = async () => {
   return token
 }
 
-export const DatabaseBackup = async () =>
-  pubsub.topic('firebase-backup').onPublish(async (message, context) => {
-    console.log('executing database backup')
-    const accessToken = await getAccessToken()
-    console.log('access token received', accessToken)
-    const url = `https://firestore.googleapis.com/v1beta1/projects/${PROJECT_ID}/databases/(default):exportDocuments`
-    // return rp.post(url, {
-    //   headers: {
-    //     Authorization: `Bearer ${accessToken}`,
-    //   },
-    //   json: true,
-    //   body: {
-    //     outputUriPrefix: `gs://${PROJECT_ID}-backups`,
-    //   },
-    // })
-  })
+// rest reference: https://cloud.google.com/firestore/docs/reference/rest/v1beta2/projects.databases/exportDocuments
+export const BackupDatabase = async () => {
+  console.log('executing database backup')
+  const accessToken = await getAccessToken()
+  console.log('access token received', accessToken)
+  const url = `https://firestore.googleapis.com/v1beta1/projects/${PROJECT_ID}/databases/(default):exportDocuments`
+  // use axios to send post request as promise
+  console.log('posting', url)
+  const timestamp: string = new Date().toString()
+  let res
+  try {
+    res = await Axios({
+      url: url,
+      method: 'post',
+      headers: {
+        Authorization: `Bearer ${accessToken}`,
+      },
+      data: {
+        outputUriPrefix: `gs://${PROJECT_ID}.appspot.com/backups/${timestamp}`,
+      },
+    })
+  } catch (error) {
+    res = 404
+  }
+  return res
+}
+
+// const createSub = async () => {
+//   pubsub
+//     .topic('firebase-backup')
+//     .onPublish(async (message, context) => BackupDatabase)
+// }

functions/src/index.ts

@@ -3,17 +3,19 @@ import * as bodyParser from 'body-parser'
 import * as cors from 'cors'
 import * as express from 'express'
 import * as functions from 'firebase-functions'
+import * as admin from 'firebase-admin'
+admin.initializeApp()
 
 // custom module imports
 import * as DB from './databaseBackup'
 
-// dev only
-const buildNumber = 1
-const app = express()
+// update on change logging purposes
+const buildNumber = 1.03
 
+// express settings to handle api
+const app = express()
 // Automatically allow cross-origin requests
 app.use(cors({ origin: true }))
-
 // use bodyparse to create json object from body
 app.use(
   bodyParser.json({
@@ -23,13 +25,11 @@ app.use(
 app.use(bodyParser.urlencoded({ extended: false }))
 
 /************ GET and POST requests ************************************************
-Redirect requests so that if a custom endpoint function exists on koboApi call it,
-otherwise pipe request directly to kobo native API
+Redirect requests so that if a custom endpoint function exists we can call them
+at /api/[endpoint]
 ************************************************************************************/
 
 app.all('*', async (req, res, next) => {
-  // log the version number for dev / tracking:
-  console.log('api build number', buildNumber)
   // get the endpoint based on the request path
   const endpoint = req.path.split('/')[1]
   // *** NOTE currently all request types handled the same, i.e. GET/POST
@@ -38,17 +38,35 @@ app.all('*', async (req, res, next) => {
     case 'db-test':
       const token = await DB.AuthTest()
       res.send(token)
+      break
+    case 'backup':
+      const response = await DB.BackupDatabase()
+      res.send(response)
+      break
     default:
       res.send('invalid api endpoint')
   }
 })
-
-// Expose Express API as a single Cloud Function:
 exports.api = functions.https.onRequest(app)
 
 app.listen(3000, 'localhost', listen => {
-  console.log('API listening on port 3000')
+  console.log(`API v${buildNumber} listening on port 3000`)
 })
 
+/************ Cron tasks ***********************************************************
+Use pubsub to automatically subscribe to messages sent from cron.
+Add/change schedule from `./functions-cron/appengine/cron.yaml`
+************************************************************************************/
+
+exports.backupFirestore = functions.pubsub
+  .topic('firebase-backup')
+  .onPublish(async (message, context) => {
+    console.log('initiating backup')
+    // run our daily db backup task
+    const backup = await DB.BackupDatabase()
+    console.log('backup:', backup)
+    return true
+  })
+
 // add export so can be used by test
 export default app

tsconfig.json

@@ -32,6 +32,7 @@
     "src/setupTests.ts",
     "config/*.js",
     "config/jest/*.js",
+    "functions-cron",
     "functions"
   ]
 }