Standard Validation: ANY schema validation DOES NOT work in `derive()` method (not sure if it previously did but it probably should)

[touhidurrr]

What version of Elysia is running?

1.4.5

What platform is your computer?

Microsoft Windows NT 10.0.26100.0 x64

What environment are you using

1.2.22

What steps can reproduce the bug?

Code

import { Elysia } from "elysia";
import { z } from "zod";

const plugin = new Elysia().guard(
  {
    headers: z.object({
      test: z.string().toLowerCase(),
    }),
    query: z.object({
      num: z.coerce.number(),
    }),
  },
  (app) =>
    app
      .derive(({ headers: { test }, query: { num } }) => {
        return { test, num };
      })
      .get(
        "*",
        ({ headers: { test: testH }, query: { num: numQ }, test, num }) => ({
          test,
          num,
          testH,
          numQ,
        }),
      ),
);

new Elysia().use(plugin).listen({ hostname: "::", port: 3000 });

Input

GET /test?num=10 HTTP/1.1
host: [::]:3000
accept: */*
Test: aBc
User-Agent: Hello-HTTP/1.8.0

What is the expected behavior?

{
  "test": "abc",
  "num": 10,
  "testH": "abc",
  "numQ": 10
}

What do you see instead?

{
  "test": "aBc",
  "num": "10",
  "testH": "abc",
  "numQ": 10
}

Additional information

@SaltyAom, here eat your desired reproduction code served fresh.

[SaltyAom]

This is an expected behavior.

Because derive runs in the same stack as transform, which is before the valuation happens (this includes type coercion)
If you want to make sure that the value has already been validated and parsed, try using resolve instead

const app = new Elysia().guard(
	{
		headers: z.object({
			test: z.string().toLowerCase()
		}),
		query: z.object({
			num: z.coerce.number()
		})
	},
	(app) =>
		app
			.resolve(({ headers: { test }, query: { num } }) => {
				return { test, num }
			})
			.get(
				'*',
				({
					headers: { test: testH },
					query: { num: numQ },
					test,
					num
				}) => ({
					test,
					num,
					testH,
					numQ
				})
			)
)

[touhidurrr]

Still it is a bug. That method confused me by showing types after validation instead of types before validation.

THIS IS UNACCEPTABLE. SUCH DECEPTION. HUH.

[SaltyAom]

That's going to be a breaking changes, so we will keep it as is until the next version

[touhidurrr]

By the way, I have a similar type issue here:
https://github.com/touhidurrr/UncivServer.xyz/blob/886faa0a0900955d1069ad79963763a1053980f1/src/routes/files/put.ts

I have a derive() in line 20 and a transform() in line 114 which is inside a put() call after the derive(). Although, the added keywords are accessible from the transform I still get a type error.

I am not sure how to fix this code. I cannot do everything inside transform since i cannot add something to context there. Also, the type issue is annoying and I do not know if this will really break in a future version. So, how do I fix this?

[touhidurrr]

That's going to be a breaking changes, so we will keep it as is until the next version

Also, I am not sure how fixing unwanted types is a breaking changes. Any time types do not conform to what is actually being done, that is a bug. This should be a bug fix, not a breaking change. Because it is what broke the code, and not the code itself.

Fixing it will throw type errors on many people's code though. And I guess that's why you want to call it a breaking change. However, they could have been assuming some code that does not work to be working as intended for some time like me. Which is also problematic from a security perspective.

[hubertoschusch]

Just experienced the same issue

[touhidurrr]

By the way, @SaltyAom. I am still unsure how to handle cases like this: #1409 (comment)

care to share some insight in it?