How can I extend mapped properties?

[jbarranis]

I have the following classes:

• Entity/EntityVm
• Customer/CustomerVm

I'm trying to map properties for both and join them together. I assume this is what Profiles can do. However, I get the this error on the line that calls .createMap inside the profile: TypeError: Cannot read property '1' of undefined

// entity.ts
export class Entity {
  @AutoMap()
  display_name: string;
  ...
}
export class EntityVm {
  @AutoMap()
  displayName: string;
  ...
}
export const entityProfile: MappingProfile = (mapper) => {
  mapper
    .createMap(Entity, EntityVm, {
      namingConventions: {
        source: new PascalCaseNamingConvention(),
        destination: new CamelCaseNamingConvention(),
      },
    })
    .forMember(
      (destination) => destination.displayName,
      mapFrom((source) => source.display_name)
    );
}

// customer.ts
export class Customer extends Entity {
   @Automap()
   custom_property: string;
}
export class CustomerVm extends EntityVm {
   @Automap()
   customProperty: string;
}
export customerProfile: MappingProfile = (mapper) => {
   // this doesn't cause an error, but I get warnings saying there are unmapped properties
   mapper.createMap(Customer, CustomerVm);
}
mapper.addProfile(entityProfile).addProfile(customerProfile);

Is this the proper way to extend mapped properties? I expect the output to be:

const mapped = mapper.map(data, Customer, CustomerVm);
// { displayName: "test", customProperty: "test" }

[micalevisk]

what if you change PascalCaseNamingConvention to SnakeCaseNamingConvention?

[jbarranis]

That doesn't resolve the issue. I feel like I may be implementing this incorrectly, which could be causing the downstream error. I updated my code above, which doesn't throw an error anymore (but it still doesn't do what I need).

[nartc]

@jbarranis hi, have you read this in the documentations? https://automapperts.netlify.app/docs/misc/limitations#property-name-with-number-or-special-characters I think this is one of the cases of limitations.

For your Entity and EntityVm, I think using SnakeCaseNamingConvention is more appropriate than PascalCaseNamingConvention given your example

[jbarranis]

hi @nartc Thanks. Yes I saw the special characters limitations documentation (also updated it to use SnakeCaseNamingConvention). I have a lot of fields in the classes, but my code example above just shows the one field. All of the fields don't seem to be mapped though.

Since I have Customer extends Entity, I want the mapper to automatically map properties I listed in entity.ts, but those don't seem to get picked up.

[nartc]

ah, have you tried?

mapper.createMap(Customer, CustomerVm, { extends: [mapper.getMapping(Entity, EntityVm)] }

[jbarranis]

Ah ha! That's what I was missing. Thanks @nartc!