# Serialization

For serialization boilerplate use [class-transformer](https://www.npmjs.com/package/class-transformer) and global interceptor `ClassSerializerInterceptor`.

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## Table of Contents <!-- omit in toc -->

- [Hide private property](#hide-private-property)
- [Show private property for admins](#show-private-property-for-admins)

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## Hide private property

If you need to hide some property in the entity you can use `@Exclude({ toPlainOnly: true })` on the column.

```ts
// /src/users/entities/user.entity.ts

import { Exclude } from 'class-transformer';

@Entity()
export class User extends EntityRelationalHelper {
  // Some code here...

  @Column({ nullable: true })
  @Exclude({ toPlainOnly: true })
  password: string;

  // Some code here...
}
```

## Show private property for admins

1. Create a controller that returns data only for admin and add `@SerializeOptions({ groups: ['admin'] })` to method:

   ```ts
   // /src/users/users.controller.ts

   // Some code here...

   @ApiBearerAuth()
   @Roles(RoleEnum.admin)
   @UseGuards(AuthGuard('jwt'), RolesGuard)
   @Controller({
     path: 'users',
     version: '1',
   })
   export class UsersController {
     constructor(private readonly usersService: UsersService) {}

     // Some code here...

     @SerializeOptions({
       groups: ['admin'],
     })
     @Get(':id')
     @HttpCode(HttpStatus.OK)
     findOne(@Param('id') id: string) {
       return this.usersService.findOne({ id: +id });
     }

     // Some code here...
   }
   ```

1. In the entity add `@Expose({ groups: ['admin'] })` to the column that should be exposed for admin:

   ```ts
   // /src/users/entities/user.entity.ts

   // Some code here...

   import { Expose } from 'class-transformer';

   @Entity()
   export class User extends EntityRelationalHelper {
     // Some code here...

     @Column({ unique: true, nullable: true })
     @Expose({ groups: ['admin'] })
     email: string | null;

     // Some code here...
   }
   ```

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