Type reflection issues

[MirrorBytes]

Describe the bug
Typescript metadata reflection does not seem to work at all. At first I thought it was related to the graphql adder, but it turns out that type-graphql works perfectly fine outside of sveltekit in an api folder served by vercel dev. This is not a permanent solution though considering there are existing issues pertaining to MIME types: #781.

Logs
This is produced in both the response and the dev console (not browser).

Error when evaluating SSR module /src/resolvers/user.ts:
Error: Unable to infer GraphQL type from TypeScript reflection system. You need to provide explicit type for argument named 'data' of 'register' of 'UserResolver' class.
    at Object.findType (/Users/bobby/Documents/phorm-kit-vercel/node_modules/type-graphql/dist/helpers/findType.js:19:15)
    at Object.getParamInfo (/Users/bobby/Documents/phorm-kit-vercel/node_modules/type-graphql/dist/helpers/params.js:10:49)
    at /Users/bobby/Documents/phorm-kit-vercel/node_modules/type-graphql/dist/decorators/Arg.js:14:25
    at eval (/src/resolvers/user.ts:14:54)
    at __decorate (/src/resolvers/user.ts:9:24)
    at eval (/src/resolvers/user.ts:74:1)
    at instantiateModule (/Users/bobby/Documents/phorm-kit-vercel/node_modules/vite/dist/node/chunks/dep-66eb515d.js:69030:166) (x18)
Error: Unable to infer GraphQL type from TypeScript reflection system. You need to provide explicit type for argument named 'data' of 'register' of 'UserResolver' class.
    at Object.findType (/Users/bobby/Documents/phorm-kit-vercel/node_modules/type-graphql/dist/helpers/findType.js:19:15)
    at Object.getParamInfo (/Users/bobby/Documents/phorm-kit-vercel/node_modules/type-graphql/dist/helpers/params.js:10:49)
    at /Users/bobby/Documents/phorm-kit-vercel/node_modules/type-graphql/dist/decorators/Arg.js:14:25
    at eval (/src/resolvers/user.ts:14:54)
    at __decorate (/src/resolvers/user.ts:9:24)
    at eval (/src/resolvers/user.ts:74:1)
    at instantiateModule (/Users/bobby/Documents/phorm-kit-vercel/node_modules/vite/dist/node/chunks/dep-66eb515d.js:69030:166)

To Reproduce
Create a new sveltekit project, use graphql adder, and create an object and resolver using type-graphql.
You can also look here: https://github.com/MirrorBytes/phorm-kit-vercel

Expected behavior
For metadata reflection to function.

Information about your SvelteKit Installation:

System:
    OS: macOS 11.2.3
    CPU: (8) arm64 Apple M1
    Memory: 373.55 MB / 8.00 GB
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 15.12.0 - /opt/homebrew/bin/node
    Yarn: 1.22.10 - /opt/homebrew/bin/yarn
    npm: 7.7.5 - /opt/homebrew/bin/npm
  Browsers:
    Brave Browser: 89.1.22.70
    Safari: 14.0.3
  npmPackages:
    @sveltejs/kit: next => 1.0.0-next.64
    svelte: ^3.29.0 => 3.36.0

• Your browser
  Brave & Safari

• Your adapter (e.g. Node, static, Vercel, Begin, etc...)
  Vercel

Severity
How severe an issue is this bug to you? Is this annoying, blocking some users, blocking an upgrade or blocking your usage of SvelteKit entirely?

It's a hindrance to me and potentially anyone using TypeScript with decorators.
I'm reproducing an existing project that currently exists in plain Svelte, so it's just a mild inconvenience at the moment, but it's ultimately blocking me from moving forward with SvelteKit.

[benmccann]

This seems too specific to GraphQL to be something that we could really address without more details as to what the cause of the issue is. You might try seeing if this happens with a standard Vite app: npm init @vitejs/app

[MirrorBytes]

Same thing occurs with mikro-orm and typeorm. I'll try creating a vite app to see if it's related.

[MirrorBytes]

It works perfectly fine with vite considering the ssr is created by the user. I'm not sure how I could replicate this issue within vite without SvelteKit.

[MirrorBytes]

@benmccann Do you think if I wrote a plugin for vite and included it in svelte.config.cjs that it would work? Here's another repo that does something similar with Nest: https://github.com/axe-me/poc-vite-node-server/blob/main/vite-plugin-node.js

[babichjacob]

Possibly related to #1327 (comment)

[benmccann]

Comment from @dummdidumm on the duplicate issue #1327:

I guess that the underlying problem is that you use Vite there, which uses ESBuild, which does not support the emitDecoratorMetadata setting. You need to find a Vite plugin that transpiles TS/JS files with the tsc compiler.

Here's the issue in the esbuild repo: evanw/esbuild#257

Maybe we should document this in troubleshooting/FAQ

[gamelaster]

(in relation of #1327) according to this comment, there is no tsc plugin for Vite (yet?).

[dummdidumm]

I found this npm package from a quick search, but I haven't tested it.

[hatemjaber]

I'm not sure if this will help anyone or if you have a better solution, but here's the link #349 to a "solution" on another thread where I was asking for help regarding the ESM error that I was getting that is similar to what you're experiencing.

If you do have a better solution please share.