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The Friday Loop

I Designed a Python SDK That Relies on… Deep Inheritance?! | Issue #61

Published about 2 months ago • 1 min read

Hey everyone,

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I love it when I come up with a design that uses exactly the things I thought were a sign of bad design.

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In this week's video I show you how to build a clean Python SDK for a REST API. The idea was simple: create a reusable base model that handles all the CRUD operations so you can just write User.find() and user.save(), without duplicating logic all over your codebase.

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Sounds great, right?

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Well, after recording the video, I realized something: not all APIs will have all CRUD methods available. Maybe some endpoints only let you retrieve resources but not update them. Or maybe you can create records but not delete them.

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So, how do you make that flexible?

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Then I considered that you could use mixins to define per model exactly which methods each resource supports. Combine that with a singleton HTTP client and multiple layers of inheritance, and suddenly you have pretty much the exact design I usually tell developers to avoid. 😅

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And yet in this specific context, it works surprisingly well.

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If you want to see how it comes together (and decide for yourself whether I’ve finally lost my mind), watch the full video.

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I’d love to hear your thoughts. Would you build your SDKs this way? Or do you have a different approach you prefer?

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As always, happy coding!

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Cheers,

Arjan

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The Friday Loop

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