Serverless APP

This application will allow creating/removing/updating/fetching PRODUCT items. Each PRODUCT item can optionally have an attachment image. Each user only has access to PRODUCT items that he/she has created.

PRODUCT items

The application should store PRODUCT items, and each PRODUCT item contains the following fields:

• productId (string) - a unique id for an item
• createdAt (string) - date and time when an item was created
• name (string) - name of a PRODUCT item (e.g. "Change a light bulb")
• category (string) - name of a PRODUCT item (e.g. "Change a light bulb")
• bestBefore (string) - date and time by which an item should be use
• sold (boolean) - true if an item was sold, false otherwise
• attachmentUrl (string) (optional) - a URL pointing to an image attached to a PRODUCT item

You might also store an id of a user who created a PRODUCT item.

Prerequisites

• Auth0 account
• GitHub account
• NodeJS version up to 12.xx
• Serverless
  • Create a Serverless account user
  • Install the Serverless Framework’s CLI (up to VERSION=2.21.1). Refer to the official documentation for more help.

  npm install -g serverless@2.21.1
  serverless --version

  • Login and configure serverless to use the AWS credentials

  # Login to your dashboard from the CLI. It will ask to open your browser and finish the process.
  serverless login
  # Configure serverless to use the AWS credentials to deploy the application
  # You need to have a pair of Access key (YOUR_ACCESS_KEY_ID and YOUR_SECRET_KEY) of an IAM user with Admin access permissions
  sls config credentials --provider aws --key YOUR_ACCESS_KEY_ID --secret YOUR_SECRET_KEY --profile serverless

Functions to be implemented

To implement this project, you need to implement the following functions and configure them in the serverless.yml file:

• Auth - this function should implement a custom authorizer for API Gateway that should be added to all other functions.

• GetProducts - should return all Products for a current user. A user id can be extracted from a JWT token that is sent by the frontend

• CreateProduct - should create a new PRODUCT for a current user. A shape of data send by a client application to this function can be found in the CreateProductRequest.ts file

It receives a new PRODUCT item to be created in JSON format that looks like this:

{
  "createdAt": "2022-09-27T20:01:45.424Z",
  "name": "CheeseCake",
  "category": "Sweets",
  "bestBefore": "2022-09-29T20:01:45.424Z",
  "Sold": false,
  "attachmentUrl": "http://example.com/image.png"
}

It should return a new PRODUCT item that looks like this:

{
  "item": {
    "productId": "123",
    "createdAt": "2022-09-27T20:01:45.424Z",
    "name": "CheeseCake",
    "category": "Sweets",
    "bestBefore": "2022-09-29T20:01:45.424Z",
    "Sold": false,
    "attachmentUrl": "http://example.com/image.png"
  }
}

• UpdateProduct - should update a PRODUCT item created by a current user. A shape of data send by a client application to this function can be found in the UpdateProductRequest.ts file

It receives an object that contains three fields that can be updated in a PRODUCT item:

{
  "name": "CheeseCake",
  "category": "Sweets",
  "Sold": true
}

The id of an item that should be updated is passed as a URL parameter.

It should return an empty body.

• DeleteProduct - should delete a PRODUCT item created by a current user. Expects an id of a PRODUCT item to remove.

It should return an empty body.

• GenerateUploadUrl - returns a pre-signed URL that can be used to upload an attachment file for a PRODUCT item.

It should return a JSON object that looks like this:

{
  "uploadUrl": "https://s3-bucket-name.s3.eu-west-2.amazonaws.com/image.png"
}

All functions are already connected to appropriate events from API Gateway.

An id of a user can be extracted from a JWT token passed by a client.

You also need to add any necessary resources to the resources section of the serverless.yml file such as DynamoDB table and S3 bucket.

Frontend

The client folder contains a web application that can use the API that should be developed in the project.

This frontend should work with your serverless application once it is developed, you don't need to make any changes to the code. The only file that you need to edit is the config.ts file in the client folder. This file configures your client application just as it was done in the course and contains an API endpoint and Auth0 configuration:

const apiId = '...' API Gateway id
export const apiEndpoint = `https://${apiId}.execute-api.us-east-1.amazonaws.com/dev`

export const authConfig = {
  domain: '...',    // Domain from Auth0
  clientId: '...',  // Client id from an Auth0 application
  callbackUrl: 'http://localhost:3000/callback'
}

Authentication

To implement authentication in your application, you would have to create an Auth0 application and copy "domain" and "client id" to the config.ts file in the client folder. We recommend using asymmetrically encrypted JWT tokens.

Best practices

To complete this exercise, please follow the best practices from the 6th lesson of this course.

Logging

The starter code comes with a configured Winston logger that creates JSON formatted log statements. You can use it to write log messages like this:

import { createLogger } from '../../utils/logger'
const logger = createLogger('auth')

// You can provide additional information with every log statement
// This information can then be used to search for log statements in a log storage system
logger.info('User was authorized', {
  // Additional information stored with a log statement
  key: 'value'
})

Grading the submission

Once you have finished developing your application, please set apiId and Auth0 parameters in the config.ts file in the client folder. A reviewer would start the React development server to run the frontend that should be configured to interact with your serverless application.

How to run the application

Backend

To deploy an application run the following commands:

cd backend
npm install
sls deploy -v

Frontend

To run a client application first edit the client/src/config.ts file to set correct parameters. And then run the following commands:

cd client
npm install
npm run start

This should start a development server with the React application that will interact with the serverless TODO application.