HW 8 - Advanced Backend

Goal

Create a shopping list app using MongoDB + Express.js, where a user can signup and login to create a shopping list. The user should be able to add and delete items within the shopping list given the index. If the user is not logged in, all operations should not be allowed.

Routes

Here is a list of routes required to build for this homework. Note that I am using 4000 as my port, but feel free to use any other port if you want.

1. User Signup Route: POST http://localhost:4000/user/signup

   1. Request Body (feel free to use your own test data):

      {
          "username": "alexwu",
          "password": "123456"
      }

   2. the response should be a token of the user

2. User Login Route: POST http://localhost:4000/user/login

   1. Request Body

      {
          "username": "alexwu",
          "password": "123456"
      }

   2. the response should be a token of the user

3. Retrieve the current shopping list: GET http://localhost:4000/shop/list

   1. The request should come with a header of token: the_user_token_here
      1. the user token should be the one that you have received through the login / signup routes
      2. if the token is incorrect, return auth error
   2. the response should be a list of items or an empty list

4. Add a new item: POST http://localhost:4000/shop/add

   1. The request should come with a header of token: the_user_token_here

      1. if the token is incorrect, return auth error

   2. Body

      {
          "item": "apple"
      }

   3. the response should be the new list: (if you have already added an "orange")

      ['orange', 'apple'];

5. Delete an item: DELETE http://localhost:4000/shop/delete

   1. The request should come with a header of token: the_user_token_here

      1. if the token is incorrect, return auth error

   2. Body

      {
          "item": "apple"
      }

   3. the response should be a new list

Steps

Step One: Setup User Auth

For all user authentication implementation, please refer to our course plan first:

This resource is also particularly helpful in building user authentication:

Authentication in NodeJS With Express and Mongo - CodeLab #1

First of all, you need to npm init and then download all the relevant packages. Then, use mongo and use auth-hw to create a database named auth-hw.

• Note that in the resource we provided, they use a cloud-based database, and we are instead using a local database.

With the user schema, since every user should be able to:

1. signup & login
2. create / modify shopping list

const UserSchema = mongoose.Schema({
  username: {
    type: String,
    required: true,
  },
  password: {
    type: String,
    required: true,
  },
  shoppinglist: {
    type: Array,
    required: false,
  },
});

You should be able to follow the resource above to create a successful authenticated app. After you have done so, now it's time to add in routes to support the shopping list app.

• Note that the resource has forgot to include how to import the auth middleware, here's how to do it:

  const auth = require('../middleware/auth');

Step Two: Shopping list app

To create the shopping list app, you need to support three routes. The GET, POST, and DELETE. All of them can be achieved by simple list operations and the help of auth middleware as seen in the resource.

You would want to start by creating a new shop.js file inside routes folder that contains all the routes for shopping list related operations. Then import the shop.js file inside index.js similar to how you have imported the user.js file. Then, you can implement the three routes there.

Here's an example of how you might implement the shop/list route:

router.get('/list', auth, async (req, res) => {
  try {
    // TODO
  } catch (e) {
    res.send({ message: 'Error in Fetching user' });
  }
});

Submission

Since all the database are local, please:

1. Film a video of you using postman sending various requests to the server & receiving the proper response back.
2. Upload the video to google drive, and submit the link to gradescope.
3. Submit the link to the Github repo to gradescope.

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Contributors

• Alex Wu