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488 points levkk | 2 comments | | HN request time: 0s | source

Hi everyone,

I've been "funemployed" for a few months and with all that free time and idle hands I wrote a full web framework (think Rails, not Flask) for Rust.

It's boring old MVC, has its own ORM, templates, background jobs, auth, websockets, migrations and more. If you're keen but don't feel like rewriting your app in a different language, Rwf has a WSGI server to run Django (or Flask) inside Rust [1], letting you migrate to Rust at your own pace without disrupting your website.

I think Rust makes a great prototyping and deploy straight to production language. Now it has yet another framework for y'all to play with.

Cheers!

[1] https://levkk.github.io/rwf/migrating-from-python/

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kvirani ◴[] No.41914951[source]
Nice, congratulations. It must feel so surreal launching this!

One of my biggest learnings from doing a bunch of web MVC through Rails over the years is that the framework should heavily discourage business logic in the model layer.

Some suggestions:

- Don't allow "callbacks" (what AR calls them) ie hooks like afterCreate in the data model. I know you don't have these yet in your ORM, but in case those are on the roadmap, my opinion is that they should not be.

- That only really works though if you not strongly encourage a service aka business logic layer. Most of my Rails app tend to have all of these as command aka service objects using a gem (library/package) like Interactor.*

* It's my view that MVC (and therefore Rails otb) is not ideal by itself to write a production-ready app, because of the missing service layer.

Also, curious why existing ORMs or query builders from the community weren't leveraged?

Disclaimer: I haven't written a line of Rust yet (more curious as the days go by). I'm more curious than ever now, thanks to you!

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ecshafer ◴[] No.41915698[source]
> One of my biggest learnings from doing a bunch of web MVC through Rails over the years is that the framework should heavily discourage business logic in the model layer.

I am curious where this comes from, because my thinking is the absolutely opposite. As much business logic as possible should belong in the model. Services should almost all be specific more complex pieces of code that are triggered from the model. Skinny controller, Fat Model, is the logic of code organization that I find makes code the easiest to debug, organize, and discover. Heavy service use end up with a lot of spaghetti code in my experience.

The other part is that from a pure OOP pov, the model is the base object of what defines the entity. Your "User" should know everything about itself, and should communicate with other entities via messages.

> Don't allow "callbacks" (what AR calls them) ie hooks like afterCreate in the data model. I know you don't have these yet in your ORM, but in case those are on the roadmap, my opinion is that they should not be.

This I agree with. Callbacks cause a lot of weird side effects that makes code really hard to debug.

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CharlieDigital ◴[] No.41917222[source]

    > I am curious where this comes from, because my thinking is the absolutely opposite. As much business logic as possible should belong in the model.
The opposite of this is what Fowler has called an "Anemic Domain Model"[0] which is ostensibly an anti-pattern. What I've learned from my own experience is that with an anemic domain model, the biggest challenge is that the logic for mutating that object is all over the codebase. So instead of `thing.DoDiscreteThang()`, there could be one or more `service1.DoDiscreteThang(thing)` and `serviceN.DoDiscreteThang(thing)` because the author of `service1` didn't know that `service2` also did the mutation.

Domain models are hard to do well and I think the SOA era brought a lot of confusion between data transfer objects, serialized objects, anemic domain models, and domain models.

[0] https://martinfowler.com/bliki/AnemicDomainModel.html

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DeathArrow ◴[] No.41923468[source]
>the biggest challenge is that the logic for mutating that object is all over the codebase

Just use immutable data structures and be done with it. In departing from old OOP views and becoming more functional programming and data oriented programming friendly, C# introduced Records, which are immutable. Probably Java and Python have similar constructs. Javascript allowed the use of immutable data since long time ago.

If you insist of using fat models, you will still mutate the data all over the place by doing calls, but you just obfuscate it.

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1. albrewer ◴[] No.41926681[source]
> Probably Java and Python have similar constructs

In Python, the closest you can get is a "frozen" dataclass, but you don't get true immutability[0]. What you _do_ get is effective enough for just about all practical use cases, except for the standard foot guns around mutable data structures.

    @dataclass(frozen=True)
    class MyModel:
        ...
[0]: https://docs.python.org/3/library/dataclasses.html#frozen-in...
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2. hansvm ◴[] No.41928956[source]
You can redefine the byte representation `True` corresponds to in python. "Immutable enough" is all you're really looking for; it somebody goes out of their way to mutate the thing then they probably had a good reason for it.