Building a GET API Lab

Learning Goals

• Build an API to handle GET requests.

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Key Vocab

• Application Programming Interface (API): a software application that allows two or more software applications to communicate with one another. Can be standalone or incorporated into a larger product.
• HTTP Request Method: assets of HTTP requests that tell the server which actions the client is attempting to perform on the located resource.
• GET: the most common HTTP request method. Signifies that the client is attempting to view the located resource.

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Instructions

This is a test-driven lab.

Run pipenv install to install the dependencies and pipenv shell to enter your virtual environment before running your code.

$ pipenv install
$ pipenv shell

Change into the server directory and configure the FLASK_APP and FLASK_RUN_PORT environment variables:

$ cd server
$ export FLASK_APP=app.py
$ export FLASK_RUN_PORT=5555

In this application, we'll be working on a JSON API to get a list of bakeries and their baked goods. We have two models, bakeries and baked goods, that have a one-to-many relationship. Here's what the ERD for these tables looks like:

The commands flask db init and flask db migrate have already been run. Run the following command to initialize the database from the existing migration script:

$ flask db upgrade head

Run the following command to seed the table with sample data:

$ python seed.py

You can run the app and explore your API in the browser by using Flask command:

$ flask run

Edit app.py to handle the following GET requests:

• GET /bakeries: returns a list of JSON objects for all bakeries in the database.
• GET /bakeries/<int:id>: returns a single bakery as JSON with its baked goods nested in a list. Use the id from the URL to look up the correct bakery.
• GET /baked_goods/by_price: returns a list of baked goods as JSON, sorted by price in descending order. (HINT: how can you use SQLAlchemy to sort the baked goods in descending order?)
• GET /baked_goods/most_expensive: returns the single most expensive baked good as JSON. (HINT: how can you use SQLAlchemy to sort the baked goods in descending order and limit the number of results?)

Once all of your tests are passing, commit and push your work using git to submit.

Examples

All Bakeries http://127.0.0.1:5555/bakeries

[
  {
    "baked_goods": [
      {
        "bakery_id": 1,
        "created_at": "2023-11-03 16:11:18",
        "id": 1,
        "name": "Chocolate dipped donut",
        "price": 2.75,
        "updated_at": null
      },
      {
        "bakery_id": 1,
        "created_at": "2023-11-03 16:11:18",
        "id": 2,
        "name": "Apple-spice filled donut",
        "price": 3.5,
        "updated_at": null
      }
    ],
    "created_at": "2023-11-03 16:11:18",
    "id": 1,
    "name": "Delightful donuts",
    "updated_at": null
  },
  {
    "baked_goods": [
      {
        "bakery_id": 2,
        "created_at": "2023-11-03 16:11:18",
        "id": 3,
        "name": "Glazed honey cruller",
        "price": 3.25,
        "updated_at": null
      },
      {
        "bakery_id": 2,
        "created_at": "2023-11-03 16:11:18",
        "id": 4,
        "name": "Chocolate cruller",
        "price": 100,
        "updated_at": "2023-11-03 16:11:18"
      }
    ],
    "created_at": "2023-11-03 16:11:18",
    "id": 2,
    "name": "Incredible crullers",
    "updated_at": null
  }
]

Bakery by ID http://127.0.0.1:5555/bakeries/1

{
  "baked_goods": [
    {
      "bakery_id": 1,
      "created_at": "2023-11-03 16:11:18",
      "id": 1,
      "name": "Chocolate dipped donut",
      "price": 2.75,
      "updated_at": null
    },
    {
      "bakery_id": 1,
      "created_at": "2023-11-03 16:11:18",
      "id": 2,
      "name": "Apple-spice filled donut",
      "price": 3.5,
      "updated_at": null
    }
  ],
  "created_at": "2023-11-03 16:11:18",
  "id": 1,
  "name": "Delightful donuts",
  "updated_at": null
}

Baked Goods By Price http://127.0.0.1:5555/baked_goods/by_price

[
  {
    "bakery": {
      "created_at": "2023-11-03 16:31:32",
      "id": 1,
      "name": "Delightful donuts",
      "updated_at": null
    },
    "bakery_id": 1,
    "created_at": "2023-11-03 16:31:32",
    "id": 2,
    "name": "Apple-spice filled donut",
    "price": 3.5,
    "updated_at": null
  },
  {
    "bakery": {
      "created_at": "2023-11-03 16:31:32",
      "id": 2,
      "name": "Incredible crullers",
      "updated_at": null
    },
    "bakery_id": 2,
    "created_at": "2023-11-03 16:31:32",
    "id": 4,
    "name": "Chocolate cruller",
    "price": 3.4,
    "updated_at": null
  },
  {
    "bakery": {
      "created_at": "2023-11-03 16:31:32",
      "id": 2,
      "name": "Incredible crullers",
      "updated_at": null
    },
    "bakery_id": 2,
    "created_at": "2023-11-03 16:31:32",
    "id": 3,
    "name": "Glazed honey cruller",
    "price": 3.25,
    "updated_at": null
  },
  {
    "bakery": {
      "created_at": "2023-11-03 16:31:32",
      "id": 1,
      "name": "Delightful donuts",
      "updated_at": null
    },
    "bakery_id": 1,
    "created_at": "2023-11-03 16:31:32",
    "id": 1,
    "name": "Chocolate dipped donut",
    "price": 2.75,
    "updated_at": null
  }
]

Most Expensive Baked Good http://127.0.0.1:5555/baked_goods/most_expensive

{
  "bakery": {
    "created_at": "2023-11-03 16:16:21",
    "id": 1,
    "name": "Delightful donuts",
    "updated_at": null
  },
  "bakery_id": 1,
  "created_at": "2023-11-03 16:16:21",
  "id": 2,
  "name": "Apple-spice filled donut",
  "price": 3.5,
  "updated_at": null
}

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Resources

• Flask - Pallets
• GET - Mozilla
• flask.json.jsonify Example Code - Full Stack Python
• SQLAlchemy-serializer - PyPI