paxcodes/grocery_api

The initial repository for PyLadies Hamburg's "Introduction to FastAPI" workshop

Grocery API

The initial repository for PyLadies Hamburg's "Introduction to FastAPI" workshop.

• 🔧 ⚙️ 💻 Before the workshop: Setup your computer
  • Part 1: Requirements
  • Part 2: Setup
• What to Expect in the Workshop

🔧 ⚙️ 💻 Before the workshop: Setup your computer

⚠️   You must run the entire set-up BEFORE the workshop.

Part 1: Requirements

The setup instructions assumes you already have the following:

• Git
• Python 3.8 (if you have an existing installation of 3.9, that works too)
• The code editor you are most comfortable using

Part 2: Setup

Instructions are based on MacOS terminal but if you use Git Bash in Windows, the instructions should be fairly the same.

✅   are instructions or "checklist" to make sure that the environment is setup properly.💡   are notes to explain what the step is about.

1. Clone this repository
   a) In your terminal, execute git clone https://github.com/paxcodes/grocery_api
   b) Still in the terminal, change your working directory: cd grocery_api

2. Create the virtual environment

   • Using your python3.8 (or 3.9), run the command [PYTHON_EXECUTABLE] -m venv --prompt "grocery_api" .venv

   • E.g. python3 -m venv --prompt "grocery_api" .venv

   • ✅ A .venv folder will be created inside the project folder.

     

3. Activate your virtual environment: source .venv/bin/activate ¹

   • ✅ Your terminal prompt will be prefixed with (grocery_api) once the virtual environment is activated.
   • ✅ Running which pip and which python should output the .venv directory inside your grocery_api folder. (e.g. /grocery_api/.venv/bin/pip and /grocery_api/.venv/bin/python)
   • ✅ Running python --version should output 3.8/3.9. If it isn't, delete your .venv folder and repeat Step #2 onwards.

4. Install dependencies: pip install -r requirements.txt

   • 💡 This installs fastapi, uvicorn, pytest, requests, etc. and their dependencies. When creating your own FastAPI project, you'd do pip install fastapi etc.
   • ✅ It should output something like, Successfully installed ... fastapi-0.65.2 ... uvicorn-0.14.0 ... pytest-6.2.4 ... requests-2.25.1
   • ✅ Running which uvicorn or which pytest should output the .venv directory inside your grocery_api folder. (e.g. /grocery_api/.venv/bin/uvicorn and /grocery_api/.venv/bin/pytest)

5. Install the project: pip install -e .

   • 💡 This will install the grocery_api package locally. This is necessary to do for pytest to work.
   • ✅ It should output something like, Successfully installed grocery-api-1.0

6. Run tests in the terminal by typing, pytest

   • ✅ It should output,

     ...
     collected 25 items
     
     tests\test_endpoints.py .                  [  4%]
     tests\crud\test_item.py ...........        [ 48%]
     tests\crud\test_store.py ...........       [ 92%]
     tests\crud\test_user.py ..                 [100%]
     
     ============== 25 passed in 0.XXs ===============
     

7. Run the server: uvicorn grocery_api.main:app

   • ✅ It should say,

     INFO:     Application startup complete.
     INFO:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)

8. Go to your browser and visit, http://127.0.0.1:8000

   • ✅ It should say, { "message": "Hello World!" }

9. Exit the server by pressing Ctrl+C in the terminal.

If you have made it all the way to the end and everything is as expected (✅), you have successfully setup your environment and are ready for the workshop!

If you are having trouble with any of the steps, reach out in PyLadies' Slack channel #city-hamburg.

1: In Windows, this would be source .venv/Scripts/activate

What to Expect in the Workshop

I will show how to implement 3 paths or endpoints in the FastAPI framework. A path to:

1. Get all items
2. Get a specific item given an Item ID (with some data validation using type-hinting)
3. Create an item resource (with some data validation using Pydantic's BaseModel class + type-hinting)

Attendees will have a chance after every section to create similar endpoints for the store data (e.g. Get all stores, get a specific store, and create a store). There is a cheatsheet available that may help when you go through the exercises / workshop and need a quick review of a concept.

If time allows, I will demonstrate:

1. Validating "outgoing" data (e.g. automatically strip sensitive data before sending data back)
2. Testing an endpoint