Victorknows / Vendor-and-sweets

Flask Code Challenge - Sweets Vendors

For this assessment, you'll be working with a vendors and sweets domain.

In this repo:

• There is a Flask application with some features built out.
• There is a fully built React frontend application.
• There are tests included which you can run using pytest -x.
• There is a file challenge-3-sweets.postman_collection.json that contains a Postman collection of requests for testing each route you will implement.

Depending on your preference, you can either check your API by:

• Using Postman to make requests
• Running pytest -x and seeing if your code passes the tests
• Running the React application in the browser and interacting with the API via the frontend

You can import challenge-3-sweets.postman_collection.json into Postman by pressing the Import button.

Select Upload Files, navigate to this repo folder, and select challenge-3-sweets.postman_collection.json as the file to import.

Setup

The instructions assume you changed into the code-challenge folder prior to opening the code editor.

To download the dependencies for the frontend and backend, run:

pipenv install
pipenv shell
npm install --prefix client

You can run your Flask API on localhost:5555 by running:

python server/app.py

You can run your React app on localhost:4000 by running:

npm start --prefix client

You are not being assessed on React, and you don't have to update any of the React code; the frontend code is available just so that you can test out the behavior of your API in a realistic setting.

Your job is to build out the Flask API to add the functionality described in the deliverables below.

Models

You will implement an API for the following data model:

The file server/models.py defines the model classes without relationships. Use the following commands to create the initial database app.db:

export FLASK_APP=server/app.py
flask db init
flask db upgrade head

Now you can implement the relationships as shown in the ER Diagram:

• A Sweet has many Vendors through VendorSweet
• A Vendor has many Sweets through VendorSweet
• A VendorSweet belongs to a Sweet and belongs to a Vendor

Update server/models.py to establish the model relationships. Since a VendorSweet belongs to a Vendor and a Sweet, configure the model to cascade deletes.

Set serialization rules to limit the recursion depth.

Run the migrations and seed the database:

flask db revision --autogenerate -m 'message'
flask db upgrade head
python server/seed.py

If you aren't able to get the provided seed file working, you are welcome to generate your own seed data to test the application.

Validations

Add validations to the VendorSweet model:

• price must have a value (i.e. can't be None)
• price cannot be a negative number

Routes

Set up the following routes. Make sure to return JSON data in the format specified along with the appropriate HTTP verb.

GET /vendors

Return JSON data in the format below:

[
  { "id": 1, "name": "Insomnia Cookies" },
  { "id": 2, "name": "Cookies Cream" }
]

GET /vendors/:id

If the Vendor exists, return JSON data in the format below:

{
  "id": 1,
  "name": "Insomnia Cookies",
  "vendor_sweets": [
    {
      "id": 2,
      "price": 45,
      "sweet": {
        "id": 2,
        "name": "Chocolate Chunk Cookie"
      },
      "sweet_id": 2,
      "vendor_id": 1
    }
  ]
}

If the Vendor does not exist, return the following JSON data, along with the appropriate HTTP status code:

{
  "error": "Vendor not found"
}

GET /sweets

Return JSON data in the format below:

[
  {
    "id": 1,
    "name": "Chocolate Chip Cookie"
  },
  {
    "id": 2,
    "name": "Brownie"
  }
]

GET /sweets/int:id

If the Sweet exists, return JSON data in the format below:

{
  "id": 1,
  "name": "Chocolate Chip Cookie"
}

If the Sweet does not exist, return the following JSON data, along with the appropriate HTTP status code:

{
  "error": "Sweet not found"
}

POST /vendor_sweets

This route should create a new VendorSweet that is associated with an existing Vendor and Sweet. It should accept an object with the following properties in the body of the request:

{
  "price": 300,
  "vendor_id": 1,
  "sweet_id": 3
}

If the VendorSweet is created successfully, send back a response with the following data:

{
  "id": 7,
  "price": 300,
  "sweet": {
    "id": 3,
    "name": "M&Ms Cookie"
  },
  "sweet_id": 3,
  "vendor": {
    "id": 1,
    "name": "Insomnia Cookies"
  },
  "vendor_id": 1
}

If the VendorSweet is not created successfully, return the following JSON data, along with the appropriate HTTP status code:

{ "errors": ["validation errors"] }

DELETE /vendor_sweets/int:id

This route should delete an existing VendorSweet. If the VendorSweet exists and is deleted successfully, return an empty object as a response:

{}

If the VendorSweet does not exist, return the following JSON data, along with the appropriate HTTP status code:

{
  "error": "VendorSweet not found"
}