dtoNames

A Vite plugin that preserves the original class names of @dto-decorated classes through minification. Without it, production builds collapse class names to short identifiers (t, e, …) and the global DTO class map keyed by clazz.name breaks — deserialize can no longer reconstruct instances.

Importing

import { dtoNames } from '@basmilius/http-client/vite';

Usage

Add the plugin to your vite.config.ts. It runs in the pre phase so it sees both authored source and the output of TypeScript's legacy decorator transform.

import { defineConfig } from 'vite';
import { dtoNames } from '@basmilius/http-client/vite';

export default defineConfig({
    plugins: [
        dtoNames()
    ]
});

For a different decorator name — for example a custom alias — pass the decorator option:

dtoNames({
    decorator: 'entity'
});

Why this exists

The @dto decorator registers each class in a global map keyed by clazz.name:

DTO_CLASS_MAP[clazz.name] = proxied;

deserialize and cloneDto look up classes by that exact name. Minifiers (esbuild, terser, oxc) rename identifiers by default, so clazz.name in a production bundle is no longer UserDto but something like t. Persisted DTOs (e.g. in localStorage) suddenly fail to hydrate, and instanceof checks via the internal NAME symbol mismatch.

dtoNames patches each decorated class to pin its name property to the authored identifier via Object.defineProperty, so the minifier can mangle the class binding without touching the runtime name string.

What it transforms

The plugin matches two shapes — the authored TypeScript source and the output of the legacy decorator transform — and injects a name override into each one.

Authored source. A class statement preceded by @dto:

@dto
export class UserDto { /* … */
}

becomes:

@dto
export class UserDto {
    static {
        Object.defineProperty(this, 'name', {value: 'UserDto', configurable: true});
    }
    /* … */
}

Compiled (legacy __decorate) output. The pattern emitted by TypeScript with experimentalDecorators:

UserDto = __decorate([dto], UserDto);

is rewritten to:

Object.defineProperty(UserDto, 'name', {value: 'UserDto', configurable: true}), UserDto = __decorate([dto], UserDto);

Either rewrite makes UserDto.name === 'UserDto' stable under any subsequent minification pass.

Options

Option	Type	Description
decorator	string	Decorator identifier to match. Default: 'dto'. Change this when re-exporting @dto under a different name.
filter	(id: string) => boolean	Predicate that decides which module ids are transformed. Default: any .js/.jsx/.ts/.tsx (and .m*/.c*) file.

Returns

Plugin — a single Vite plugin. Add it to the plugins array.

Type signature

declare function dtoNames(options?: Options): Plugin;

type Options = {
    readonly decorator?: string;
    readonly filter?: (id: string) => boolean;
};

See also

• @dto — the decorator whose class names this plugin preserves.
• serialize / deserialize — the helpers that rely on clazz.name for round-tripping.
• DTO pattern guide — practical walkthrough.