C#•2y ago

❔ ✅ custom mapper and resolvers

Hello, I've been trying to use automapper for a while, but now I've decided to just replace it with my own mapping methods, I've created static extension class, but there is one problem with it. Mapping class is now static, but my resolvers classed need to dependency inject services to work, how I am supposed to call my resolver in static class? MappingExtensions:

public static class MappingExtensions
{
    public static PublicAd MapToPublicAd(this Ad ad, User user)
    {
        return new PublicAd
        {
            Claimed = ad.Claimed,
            Distance = // I don't know
        };
    }
...

public static class MappingExtensions
{
    public static PublicAd MapToPublicAd(this Ad ad, User user)
    {
        return new PublicAd
        {
            Claimed = ad.Claimed,
            Distance = // I don't know
        };
    }
...

DistanceResolver:

public class DistanceResolver
{
    private readonly IDistanceService _distanceService;

    public DistanceResolver(IDistanceService distanceService)
    {
        _distanceService = distanceService;
    }

    public double Resolve(Ad ad, User user)
    {
        if (user is null)
        {
            throw new ArgumentException($"No valid user passed to");
        }

        if (user.Municipality is null || source.Municipality is null)
        {
            return -1d;
        }

        return _distanceService.GetDistanceInKm(
            ad.Municipality.Location!.Y, 
            ad.Municipality.Location!.X,
            user.Municipality.Location!.Y,   
            user.Municipality.Location!.X
        );
    }
}

public class DistanceResolver
{
    private readonly IDistanceService _distanceService;

    public DistanceResolver(IDistanceService distanceService)
    {
        _distanceService = distanceService;
    }

    public double Resolve(Ad ad, User user)
    {
        if (user is null)
        {
            throw new ArgumentException($"No valid user passed to");
        }

        if (user.Municipality is null || source.Municipality is null)
        {
            return -1d;
        }

        return _distanceService.GetDistanceInKm(
            ad.Municipality.Location!.Y, 
            ad.Municipality.Location!.X,
            user.Municipality.Location!.Y,   
            user.Municipality.Location!.X
        );
    }
}

10 Replies

Jothay•2y ago

The code calling the MapToPublicAd method can pass in the IDistanceResolver as an arg for it to call, or you'll have to call it outside the func and then pass in the value for the Distance prop public static PublicAd MapToPublicAd(this Ad ad, User user, IDistanceResolver resolver) Distance = resolver.Resolve(ad, user) public static PublicAd MapToPublicAd(this Ad ad, User user, decimal distance) Distance = distance I usually pull those parts of maps out of the mapping class and just do them after-the-fact Let the mapper handle the parts that directly read off of data, and calculated equations to a separate action