Persist user data to DB and authenticate against DB

Author: Brent Engelbrecht

src/datastore/repository.js

@@ -1,12 +1,43 @@
 
-function saveUserDetails() {
+let users
+let api
+
+async function dbClient(connection) {
+  if (users) {
+    return
+  }
+
+  try {
+    api = await connection.db(process.env.DB_NAMESPACE)
+    users = await api.collection(process.env.DB_COLLECTION)
+  } catch (e) {
+    console.error(`Unable to establish a collection handle to apiUsers: ${e}`)
+  }
+}
+
+async function saveUserDetails(userDetails) {
+  try {
+    await users.insertOne(userDetails, { w: 'majority' })
+    return { success: true }
+  } catch (e) {
+    if (String(e).startsWith("MongoError: E11000 duplicate key error")) {
+      return { error: "A user with that id already exists." }
+    }
+    console.error(`Error occurred while adding new user, ${e}.`)
+    return { error: e }
+  }
 }
 
-function getUserDetails() {
+async function getUserDetails(userName) {
+  return await users.findOne({ "userName": userName.toLowerCase() })
 }
 
-function authenticateUser(username, password) {
-  return { username: username.toLowerCase() }
+async function authenticateUser(userName, password) {
+  const userDetails = await users.findOne({ "userName": userName.toLowerCase(), "password": password })
+  if (userDetails) {
+    return true
+  }
+  return false
 }
 
-module.exports = { saveUserDetails, getUserDetails, authenticateUser }
+module.exports = { dbClient, saveUserDetails, getUserDetails, authenticateUser }

src/routes/users.js

@@ -1,14 +1,20 @@
 const jwt = require('jsonwebtoken')
 const repository = require('../datastore/repository')
 
-function register (ctx) {
+async function register (ctx) {
+  const payload = JSON.parse(ctx.request.body)
   const {
     firstName,
     lastName,
     userName,
     password,
     email
-  } = ctx.request
+  } = payload
+
+  const userDetails = await repository.getUserDetails(userName)
+  if (userDetails) {
+    ctx.throw(409, 'User already exists.')
+  }
 
   repository.saveUserDetails({
     firstName,
@@ -17,16 +23,18 @@ function register (ctx) {
     password,
     email
   })
+
+  ctx.response.status = 201
 }
 
-function login (ctx) {
-  const { username, password } = ctx.request.body
-  if (!username) ctx.throw(422, 'Username required.')
+async function login (ctx) {
+  const { userName, password } = ctx.request.body
+  if (!userName) ctx.throw(422, 'Username required.')
   if (!password) ctx.throw(422, 'Password required.')
 
-  const userDetails = repository.authenticateUser(username, password) 
+  const userDetails = await repository.authenticateUser(userName, password)
   if (!userDetails) {
-    ctx.throw(err.status || 401, err.text)
+    ctx.throw(401, 'Not authorised.')
   }
 
   const payload = { sub: userDetails.username }

src/server.js

@@ -6,9 +6,20 @@ const bodyParser = require('koa-bodyparser')
 const authorisation = require('./middleware/authorisation')
 const userRoutes = require('./routes/users')
 const fileRoutes = require('./routes/files')
+const repository = require('./datastore/repository')
+const MongoClient = require('mongodb').MongoClient
 
 const port = process.env.PORT || 5000
 
+MongoClient
+  .connect(`${process.env.DB_URL}`, { useNewUrlParser: true })
+  .catch(err => {
+    console.error(err.stack)
+  })
+  .then(client => {
+    repository.dbClient(client)
+  })
+
 const app = new Koa()
 const router = koaRouter()