Reversed order of key/value pairs in JSON after mapping

[friedScotch]

Is there an existing issue for this?

• I have searched the existing issues

Describe the issue

Hello @nartc,

hats off for being so active in the first place.
I'm experiencing something similar to #181 . The Mapper is configured properly and works as well. Just the JSON key/value pairs after mapping are in reversed order.

Models/DTOs/VMs

UserEntity Class:

export class UserEntity{     

@AutoMap()
id: number;

@AutoMap()
name: string;

@AutoMap()
sharedInfo: string;

password: string;
}

UserResponse Class

export class UserResponse{    

@AutoMap()
id: number;

@AutoMap()
name: string;

@AutoMap()
sharedInfo: string;
}

Mapping configuration

This is the automapper profile:

@Injectable()
export class UserProfile extends AutomapperProfile {
  constructor(@InjectMapper() mapper: Mapper) {
    super(mapper);
  }

  get profile(): MappingProfile {
    return (mapper) => {
      createMap(mapper, UserEntity, UserResponse);
    };
  }
}

@Injectable()
export class UserService {
    users: UserEntity[] = users;

    constructor(@InjectMapper() private readonly mapper: AutoMapper) { }
    
    async getAllUsers(): Promise<UserResponse[]>{
        return toPromise(this.mapper.mapArray(this.users, UserEntity, UserResponse));
    }
    ...
}

Steps to reproduce

No response

Expected behavior

Expected:

{
"users": [
             {
               "id": 456,
               "name": "username",
               "sharedInfo": "This is shared info block"
             }
   ]
}

Actual response from mapper

{
"users": [
             {
               "sharedInfo": "This is shared info block",              
               "name": "username",
                "id": 456
             }
   ]
}

Screenshots

No response

Minimum reproduction code

No response

Package

• I don't know.
• @automapper/core
• @automapper/classes
• @automapper/nestjs
• @automapper/pojos
• @automapper/mikro
• @automapper/sequelize
• Other (see below)

Other package and its version

No response

AutoMapper version

8.4.1

Additional context

NestJs v8.0.0
Node v16.16.0

[nartc]

Thank you for reporting. I'll take a look as soon as I find some time.

[nartc]

Please give 8.7.0 a try

EDIT: I'll give you some context about the behavior if you're interested.

The "problem" was from: mappingProperties.unshift() in createInitialMapping() function. createInitialMapping() is the function that gets called when you call: createMap(mapper, Source, Destination).

Normally, the Mapper will grab the metadata from AutoMap and process those into MappingProperties. These are so-called "Auto Configuration".

Optionally, you can pass one or many forMember() calls to "customize" the mapping instruction for each property. These "Manual/Custom Configurations" are always run FIRST.

mappingProperties.unshift() makes sure that the "Auto Configurations" are placed BEFORE the "Manual/Custom Configurations" because the "Manual/Custom Configurations" should take precedence over the "Auto Configurations"

export class UserEntity {
   @AutoMap()
   id!: number;
}

export class UserResponse {
   @AutoMap()
   id!: number;
}

createMap(mapper, UserEntity, UserResponse); // "id" is auto-configured
createMap(mapper, UserEntity, UserResponse,
   forMember(d => d.id, fromValue(Math.random())) // "id" is custom-configured and this should take precedence
)

[friedScotch]

@nartc Whoa thanks for the lightning fast fix AND detailed info. I throughly enjoyed reading it! 👍