Serverless TODO

This project is part of the Cloud Developer Nanodegree. The goal of this project to implement a simple TODO application using AWS Lambda and Serverless framework.

Functionality of the application

This application allows to create/remove/update/fetch TODO items. Each TODO item can optionally have an attachment image. Each user only has access to TODO items that he/she has created.

TODO items

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

todoId (string) - a unique id for an item
userId (string) - the user id that created this todo item
createdAt (string) - date and time when an item was created
name (string) - name of a TODO item (e.g. "Change a light bulb")
dueDate (string) - date and time by which an item should be completed
done (boolean) - true if an item was completed, false otherwise
attachmentUrl (string) (optional) - a URL pointing to an image attached to a TODO item

Functions implemented

To implement this project, the following functions have been configured:

Auth - this function implement a custom authorizer for API Gateway that should be added to all other functions.
GetTodos - return all TODOs for a current user. A user id can be extracted from a JWT token that is sent by the frontend

It returns data that looks like this:

{
  "items": [
    {
      "todoId": "123",
      "createdAt": "2019-07-27T20:01:45.424Z",
      "name": "Buy milk",
      "dueDate": "2019-07-29T20:01:45.424Z",
      "done": false,
      "attachmentUrl": "http://example.com/image.png"
    },
    {
      "todoId": "456",
      "createdAt": "2019-07-27T20:01:45.424Z",
      "name": "Send a letter",
      "dueDate": "2019-07-29T20:01:45.424Z",
      "done": true,
      "attachmentUrl": "http://example.com/image.png"
    },
  ]
}

CreateTodo - create a new TODO for a current user. A shape of data send by a client application to this function can be found in the CreateTodoRequest.ts file

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

{
  "name": "Buy milk",
  "dueDate": "2019-07-29T20:01:45.424Z",
}

It returns a new TODO item that looks like this:

{
  "item": {
    "todoId": "123",
    "createdAt": "2019-07-27T20:01:45.424Z",
    "name": "Buy milk",
    "dueDate": "2019-07-29T20:01:45.424Z",
    "done": false,
    "attachmentUrl": "http://example.com/image.png"
  }
}

UpdateTodo - update a TODO item created by a current user. A shape of data send by a client application to this function can be found in the UpdateTodoRequest.ts file

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

{
  "name": "Buy bread",
  "dueDate": "2019-07-29T20:01:45.424Z",
  "done": true
}

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

It returns an empty body.

DeleteTodo - should delete a TODO item created by a current user. Expects an id of a TODO item to remove.

It returns an empty body.

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

It returns 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.

The serverless.yml file includes all of these functions as well as a DynamoDB table and a S3 bucket in the resources.

Authentication

This app is using Auth0 to implement authentication. The configuration of the "domain" and "client id" are available on the client/src/config.ts file.

How to run the application

Prerequisite

Install serverless npm install -g serverless
Set up a new user in IAM named "serverless" with Programmatic access and with AdministratorAccess policy attached and save the access key and secret key.
Configure serverless to use the AWS credentials you just set up: sls config credentials --provider aws --key YOUR_ACCESS_KEY --secret YOUR_SECRET_KEY --profile serverless