This is a starting point for Python solutions to the "Build Your Own Redis" Challenge.

In this challenge, you'll build a toy Redis clone that's capable of handling basic commands like PING, SET and GET. Along the way we'll learn about event loops, the Redis protocol and more.

Note: If you're viewing this repo on GitHub, head over to codecrafters.io to signup for early access.

Usage

  1. Ensure you have python (3.8) installed locally
  2. Run ./spawn_redis_server.sh to run your Redis server, which is implemented in app/main.py.
  3. Commit your changes and run git push origin master to submit your solution to CodeCrafters. Test output will be streamed to your terminal.

Passing the first stage

CodeCrafters runs tests when you do a git push. Make an empty commit and push your solution to see the first stage fail.

git commit --allow-empty -m "Running tests"
git push origin master

You should see a failure message that says it wasn't able to connect to port 6379.

Go to app/main.py and uncomment the server implementation. Commit and push your changes, and you'll now see the first stage pass.

Time to move on to the next stage!

Troubleshooting

module socket has no attribute create_server

When running your server locally, you might see an error like this:

Traceback (most recent call last):
  File "/.../python3.7/runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "/.../python3.7/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/app/app/main.py", line 11, in <module>
    main()
  File "/app/app/main.py", line 6, in main
    s = socket.create_server(("localhost", 6379), reuse_port=True)
AttributeError: module 'socket' has no attribute 'create_server'

This is because socket.create_server was introduced in Python 3.8, and you might be running an older version.

You can fix this by installing Python 3.8 locally and using that.

If you'd like to use a different version of Python, change the language_pack value in codecrafters.yml.