This is an in-progress example rate limiter module for learning about decorators and rate limiting.

Python 3.7

From outside the project folder, run the following commands, substituting name:tag for some some new docker image name and optionally a tag. If you don't want to accidentally overwrite an existing name:tag combination, first check your existing list using docker image ls

docker build -t <name:tag> rate-limiter-python/
docker run -it -p 5000:5000 <name:tag>

You should see the following:

• Serving Flask app "hello"
• Running on https://0.0.0.0:5000/ (Press CTRL+C to quit)

Navigate to https://localhost:5000?apikey=user. TODO: get user securely from auth header

Since we're using a dummy certificate to authenticate this for demonstration purposes, you will see a security warning. Since localhost is secure, it is fine to accept this warning and proceed to the page.

NB. If port 5000 is already occupied, change the second occurrence of 5000 in the docker run command to an unoccupied port, and change the port of the app address to the same thing.

cd limiter
python -m unittest discover

TODO: add tests for limiter

The name of the function which the limit decorator wraps is used as the key of the database (implemented as a dictionary) which records the number and time of accesses to the endpoint. If you change a function name, you will need to update the corresponding key.

If you want to implement a rate limit that is shared across multiple endpoints, you must provide a unique name for this shared rate limit which will be used as the key of the database (dictionary). This must not be the same of the name of any endpoint function.