This document discusses developing a mypy Playground using Python and Docker. It introduces mypy, a static type checker for Python, and describes building a web application using Python and Docker that allows running mypy on code snippets or files stored in code repositories like GitHub Gists. Key aspects covered include using the Docker API in Python to run mypy in isolated Docker containers to check code and returning results to the user interface.

1. Python Docker
mypy Playground
Yusuke Miyazaki @ymyzk
PyCon mini Osaka 2018
2018/5/19 Grand Front Osaka
Development of mypy Playground with Python and Docker

2. • / @ymyzk
• @ / Indeed
• Python 6 + / PyCon JP / …
• ymyzk.com

3. • : → (2 ) → ( )
• Python Boot Camp in
• IT CAMPHOR-
( )

4. Python ?
Python Docker
mypy Playground

5. •
• mypy Playground
• Python + Docker mypy
•
•

6. mypy Playground

7. mypy ? 🙋

8. mypy ? 🙋

9. mypy
• Python
• PEP 484 / 526
• CLI
def greeting(name: str) -> str:
return f"Hello, {name}!!"
greeting("Taro")
greeting(123) # error: Argument 1 to "greeting" has
# incompatible type "int"; expected "str"

10. mypy Playground: mypy-play.net
• mypy Web
•
• mypy
•
• Gist

11. mypy Playground: URL HERE

12. mypy Playground
• mypy
• /tmp/test1.py
•
• mypy typeshed

13. :
•
• : The Go Playground / Rust Playground / Scastie (Scala)
•
• : Wandbox
• : ymyzk/awesome-playgrounds

14. mypy Playground
UI

15.
UI
Ace Bootstrap Bottle Docker

16. •
• CPU

17. •
• …
•
•
• import
•

18. Python + Docker
mypy

19. Docker ? "

20. Docker
•
• : jail / LXC / systemd-nspawn
•
• Linux ( cgroups)
•

21. Docker
•
•
• Docker Hub
•
• Docker
• Docker

22. Python Docker
• Docker Engine API HTTP API
• CLI docker API
• Python Docker docker-py

23. • CLI
• docker-py
Python Docker
$ docker run ubuntu echo Hello Osaka!
import docker
client = docker.from_env()
client.containers.run("ubuntu", "echo Hello Osaka!")

24. mypy
1. mypy Docker
2. mypy
3.

25. Docker
# typed-ast manylinux1
FROM python:3.6
RUN pip install mypy
# root
USER nobody
CMD ["mypy"]

26. c = client.containers.create(
"ymyzk/mypy-playground:sandbox",
command="mypy main.py",
network_mode="none", #
mem_limit="128m", #
pids_limit=32,
cap_drop="ALL",
security_opt=["no-new-privileges"])

27. # tar (Docker API )
tarball = create_archive(source)
c.put_archive("/tmp", tarball)#
c.start() # mypy
exit_code = c.wait() #
#
stdout = c.logs(stdout=True, stderr=False).decode("utf-8")
stderr = c.logs(stdout=False, stderr=True).decode("utf-8")
c.remove()

28. • Docker mypy
•
• ?
• :

30. Docker in Docker (dind)
• Docker Docker
• Docker
Docker Docker

31. Docker in Docker
• Docker
• Docker
• Docker

32. Docker in Docker
• vfs
•
dind

33. mypy Playground
• I/O
• mypy
• mypy
• WSGI
•

34. mypy Playground with asyncio
• Bottle Tornado
• Docker asyncio aiodocker
• aiodocker docker-py

36. • mypy Playground
•
• typeshed / PEP 561
• Facebook Pyre
• : / dmypy

37. • Python + Docker mypy Playground (mypy-play.net)
• Web Python
• Docker
• Twitter: @mypy_playground / GitHub: ymyzk/mypy-playground
• !!