Group Mapping Logic with Profile

In the previous section, you've created your first Mappings for Bio <-> BioDto and User <-> UserDto

createMap(
    mapper,
    Bio,
    BioDto,
    typeConverter(Date, String, (date) => date.toDateString()),
    namingConventions(new CamelCaseNamingConvention())
);

createMap(
    mapper,
    User,
    UserDto,
    forMember(
        (destination) => destination.fullName,
        mapFrom((source) => source.firstName + ' ' + source.lastName)
    )
);

This approach works completely fine but when the application starts growing with more entities, these configurations will also start growing. Profile is a way to group Mappings of related entities into a MappingProfile, so you can focus on a specific domain when working with a certain set of entities.

Your first MappingProfile

MappingProfile is a function that will be called with the Mapper and returns void.

const bioProfile: MappingProfile = (mapper) => {
    createMap(
        mapper,
        Bio,
        BioDto,
        typeConverter(Date, String, (date) => date.toDateString()),
        namingConventions(new CamelCaseNamingConvention())
    );
};

When you have more models/DTOs related to Bio, you can group them all under bioProfile. Repeat the process with User <-> UserDto.

To use MappingProfile, call addProfile() with your Mapper object and the MappingProfile

addProfile(mapper, bioProfile);
addProfile(mapper, userProfile);

tip

Order of the MappingProfile matters. bioProfile goes first because userProfile depends on Mapping<Bio, BioDto>

Share MappingConfiguration

One benefit of using MappingProfile is that you can share some common MappingConfiguration for all createMap() inside of a specific MappingProfile.

Let's assume you have the following Mappings

const bioProfile: MappingProfile = (mapper) => {
    const camelCaseNamingConvention = new CamelCaseNamingConvention();
    createMap(
        mapper,
        Bio,
        BioDto,
        namingConventions(camelCaseNamingConvention),
        extend(Base, BaseDto)
    );

    createMap(
        mapper,
        Bio,
        BioInformationDto,
        namingConventions(camelCaseNamingConvention),
        extend(Base, BaseDto)
    );

    createMap(
        mapper,
        Bio,
        MinimalBioDto,
        namingConventions(camelCaseNamingConvention),
        extend(Base, BaseDto)
    );
};

Instead of repeating the same MappingConfiguration on each createMap() like above, you can pass the MappingConfiguration in addProfile() instead

const bioProfile: MappingProfile = (mapper) => {
    createMap(mapper, Bio, BioDto);
    createMap(mapper, Bio, BioInformationDto);
    createMap(mapper, Bio, MinimalBioDto);
};

addProfile(
    mapper,
    bioProfile,
    namingConventions(new CamelCaseNamingConvention()),
    extend(Base, BaseDto)
);