[Question] - How to Derive(ts) for Complex Data Structures from External Crates? #163

[barel-mishal]

Hello,

I appreciate the ts-rs crate and use it frequently. However, I've encountered some edge cases that I need assistance with. I hope my issue can be resolved, or perhaps I'm just not using ts-rs correctly.

In one of my applications, I use SurrealDB, and it includes a struct called Thing. Here's how Thing and its associated Id enum are defined:

#[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Deserialize, Store, Hash)]
pub struct Thing {
	pub tb: String,
	pub id: Id,
}

#[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Serialize, Deserialize, Hash)]
pub enum Id {
	Number(i64),
	String(String),
	Array(Array),
	Object(Object),
}

These shapes of structs are extracted from the surrealdb crate, and I can't modify the code to add derive(TS...).

Currently, my application is throwing the following error:

error[E0277]: the trait bound `surrealdb::sql::Thing: TS` is not satisfied
   ...

As a workaround, I've used the following code:

#[derive(TS, Debug, Serialize, Deserialize)]
#[ts(export, export_to = "../../src/utiles/types_rust_bindings/")]
pub struct User {
    #[ts(type = "string")]
    pub id: Thing,
    ... other fields ...
}

Is there a better approach to address this situation? How can I make my types in TypeScript have the same type as they are presented in SurrealDB structs? Any guidance would be greatly appreciated.

Thank you!

[NyxCode]

hey, thanks for reaching out.
There are a couple of solutions/workarounds:

• Create a PR to add support for the types you need, gated behind a feature
• use the #[ts(type = .. )] override. This works well for simple types. For more complex structs, you could write the type out yourself and put it in a .d.ts file and refer to it in the type override.
• Create a wrapper type and inplement TS by hand, or implement TS for your entire type by hand

[barel-mishal]

I think the third option will work better for this case. How can I implement the TS? I am little bit new to rust so I do not really know where to look. Do you have any example?

I think the third will be better because this is very complex structure and I need just part of it. Another this type is very specific to surrealdb so it will be better to I think to separate this into external support caret

[NyxCode]

I think that's the most cumbersome tbh. Can't you just write the TypeScript type of Thing yourself, put it in a surreal.d.ts file, and use #[ts(type = "Thing")] whenever you have a field of type Thing in your structs?

[NyxCode]

Again, the "real" solution here is to add support for the surrealdb crate in a PR to ts-rs, but someone will have to do that.

[barelmishal]

I will ask them then thanks @NyxCode