Design document for social cross-posting integration

[yoavartzi]

Create a design document for social media cross posting. Please review API of prominent networks to design a general abstraction. We will likely start with BlueSky, but adding networks in the future should require only implementing code specific to each network (this includes linking the account to get authorization to post, and cross-poting)

[mistydqwq]

I have a question: do you prefer each platform to be completely separate, or there could be some overlap?

This mainly affects the decision of whether all platforms should call a common userService.installOAuth method on the frontend, which takes a platform parameter and delegates the logic to the backend, where a factory instantiates the appropriate service for the given platform. Or should each platform have its own install method, eliminating the need for a shared userService method and directly invoking each platform's specific implementation?

The advantage of the first approach is that the tRPC implementation remains simple—there’s only one userService.installOAuth method to call, and the backend handles platform-specific logic through the factory. This is how Slack OAuth is currently implemented.

The advantage of the second approach is that services are completely independent, with no shared methods, but at the cost of reduced code reuse. Each platform would function as an entirely separate entity, and tRPC might explode due to the need to define many routes—one for each platform.

[yoavartzi]

I think we can provide some general services for the different platforms to use. Right?
This way it won't create dependency, because the service code will provide a well-defined service. The code for each platform can use it, or not (if it's not standard)

What do you think?

[mistydqwq]

I don't think we have general services for different platforms. The general services that shared by all the platforms could only be database services I guess. Because even though for those function that every platform needs, such as generateOAuthLink, refreshToken, exchangeTokenWithCode, different platform will still have different needs( like different platform need us to construct different redirect url).

So I think the best we can do is to provide a unified interface with functions that all the platforms share(just like the functions mentioned above) and let different platforms' service to implement this interface. But if you want to reuse codes as much as possible, I think we have to make these platforms' implementations overlap(like I mentioned last time, they share the same generateOAuthLink function and use a param 'platform' to distinguish the logic, etc.).

Any thoughts?