Show HN: Modguard – a lightweight Python tool for enforcing modular design(github.com)
github.com
Show HN: Modguard – a lightweight Python tool for enforcing modular design
https://github.com/Never-Over/modguard
6 comments
Great idea, definitely ran into a lot of these problems at my last gig. Will try this out next time I'm working on a python project.
> specific nonstandard custom syntax to access modules/submodules such as getattr or dynamically generated namespaces will not be caught by modguard
Are any plans to get modguard to take these cases into account? I imagine this is harder without doing anything at runtime.
> specific nonstandard custom syntax to access modules/submodules such as getattr or dynamically generated namespaces will not be caught by modguard
Are any plans to get modguard to take these cases into account? I imagine this is harder without doing anything at runtime.
Yup! We have looked into runtime checks to supplement the static analysis. From talking to other users, they've used similar runtime checks in CI and staging environments to catch dynamic imports and even check specific method usages.
Awesome! Huge problem in a lot of Python codebases, and hard to get around this problem without trying to go all in on type-safety. Even so, you don't get granular control like this.
Very cool..exciting to see you tackling the modular architecture challenge head-on, and also wrt to dynamically imported modules..would also be interesting to see some sort of IDE integration for real-time feedback directly in the development workflow. Would be nice to have a discord community around this!
Looks really interesting for managing modular codebases!
This is sick, it would be amazing if I could get complete backend codebase a OOTB with this, ruff, and other meta Python packages.
Hi HN! I'm one of the developers of modguard.
I'm excited to get feedback from you all, and I'm happy to answer any questions you might have!
I'm excited to get feedback from you all, and I'm happy to answer any questions you might have!
We built modguard to solve a recurring problem that we've experienced on software teams - code sprawl. Over time, cross-module imports would tightly couple together what used to be independent domains, and eventually create "balls of mud". This made it harder to test, and harder to make changes. Mis-use of modules which were intended to be private would then degrade performance and even cause security incidents.
This would happen for a variety of reasons:
- Junior developers had a limited understanding of the existing architecture and/or frameworks being used
- It's significantly easier to add to an existing service than to create a new one
- Python doesn't stop you from importing any code living anywhere
- When changes are in a 'gray area', social desire to not block others would let changes through code review
- External deadlines and management pressure would result in "doing it properly" getting punted and/or never done
Attempts to fix this problem always came up short. Inevitably, standards guides would be written, and stricter attempts would be made to enforce those guides. Teams would lead developer education efforts, and restrict code review. These approaches each had their own flaws, and didn't scale.
The solution is to explicitly define a module's boundary and public interface in code, and enforce those domain boundaries through CI. This means that introducing a new cross-module dependency required explicitly changing the public interface or the boundary itself. This is a significantly smaller and well-scoped set of changes that can be maintained and managed by those who understood the intended design of the system.
modguard is:
- fully open source
- able to be adopted incrementally
- implemented with no runtime footprint
- a standalone library with no external dependencies
- interoperable with your existing system (cli, generated config)
We hope you try it out! We’d love your feedback.
Github - https://github.com/Never-Over/modguard
Docs - https://never-over.github.io/modguard/
[email protected]