AutoMapper.Extensions.OData

Creates LINQ expressions from ODataQueryOptions and executes the query.

NuGet Package Downloads

Usage

To use:

• Configure object maps with explicit expansion.
• Call the GetAsync or GetQueryAsync extension method from your OData controller. IMapper is an AutoMapper interface.

    public class CoreBuildingMappings : AutoMapper.Profile
    {
        public CoreBuildingMappings()
        {
            CreateMap<TBuilding, CoreBuilding>()
                .ForMember(d => d.Name, o => o.MapFrom(s => s.LongName))
                .ForMember(d => d.Tenant, o => o.MapFrom(s => s.Mandator))
                .ForAllMembers(o => o.ExplicitExpansion());

            CreateMap<TBuilder, OpsBuilder>()
                .ForAllMembers(o => o.ExplicitExpansion());
            CreateMap<TCity, OpsCity>()
                .ForAllMembers(o => o.ExplicitExpansion());
        }
    }

public static async Task<ICollection<TModel>> GetAsync<TModel, TData>(this IQueryable<TData> query, IMapper mapper, ODataQueryOptions<TModel> options, HandleNullPropagationOption handleNullPropagation = HandleNullPropagationOption.Default);
public static async Task<IQueryable<TModel>> GetQueryAsync<TModel, TData>(this IQueryable<TData> query, IMapper mapper, ODataQueryOptions<TModel> options, HandleNullPropagationOption handleNullPropagation = HandleNullPropagationOption.Default);

    public class CoreBuildingController : ODataController
    {

	private readonly IMapper _mapper;
        public CoreBuildingController(MyDbContext context, IMapper mapper)
        {
            Context = context;
            _mapper = mapper;
        }

        MyDbContext Context { get; set; }

        [HttpGet]
        public async Task<IActionResult> Get(ODataQueryOptions<CoreBuilding> options)
        {
            return Ok(await Context.BuildingSet.GetQueryAsync(_mapper, options));
        }
    }

Using the EnableQueryAttribute

Using EnableQuery with AutoMapper.Extensions.OData will result in some operations being applied more than once e.g. in the tests, if TMandator has a total of two records then without EnableQuery applied to the controller action, the OData query http://localhost:16324/opstenant?$skip=1&$top=1&$orderby=Name will return one record as expected. However with EnableQuery applied no records will be returned because the skip operation has been applied twice.

While EnableQuery will result in some operations being applied more than once, one can create a custom EnableQueryAttribute to ignore the QueryOptions that are applied by AutoMapper.Extensions.OData.

   public class MyCustomEnableQueryAttribute : EnableQueryAttribute
    {
        public override IQueryable ApplyQuery(IQueryable queryable, ODataQueryOptions queryOptions)
        {
            var ignoreQueryOptions =
                AllowedQueryOptions.Skip |
                AllowedQueryOptions.Top |
                AllowedQueryOptions.Filter |
                AllowedQueryOptions.Expand |
                AllowedQueryOptions.Select |
                AllowedQueryOptions.OrderBy |
                AllowedQueryOptions.Count;

            return queryOptions.ApplyTo(queryable, ignoreQueryOptions);
        }
    }

Aggregation

With a custom EnableQueryAttribute there is limited support for grouping and aggregation. Grouping and aggregation on navigation properties is not supported. Example can be found in the AggregationTests

    public class AllowApplyAttribute : EnableQueryAttribute
    {
        public override IQueryable ApplyQuery(IQueryable queryable, ODataQueryOptions queryOptions)
        {
            var ignoreQueryOptions =
                AllowedQueryOptions.Skip |
                AllowedQueryOptions.Top |
                AllowedQueryOptions.Filter |
                AllowedQueryOptions.Expand |
                AllowedQueryOptions.Select |
                AllowedQueryOptions.OrderBy |
                AllowedQueryOptions.Count;

            return queryOptions.ApplyTo(queryable, ignoreQueryOptions);
        }

        public override void OnActionExecuted(ActionExecutedContext actionExecutedContext)
        {
            if (actionExecutedContext is null)
            {
                throw new ArgumentNullException(nameof(actionExecutedContext));
            }

            if (actionExecutedContext.HttpContext.Response != null &&
                IsSuccessStatusCode(actionExecutedContext.HttpContext.Response.StatusCode) &&
                actionExecutedContext.Result is ObjectResult content &&
                content.Value != null &&
                content.DeclaredType == null)
            {
                // To help the `ODataOutputFormatter` to determine the correct output class
                // the `content.DeclaredType` needs to be set before appling the `$apply`-option
                // so that a valid `OData`-result is produced
                // https://github.com/OData/AspNetCoreOData/blob/4de92f52a346606a447ec4df96c5f3cd05642f50/src/Microsoft.AspNetCore.OData/Formatter/ODataOutputFormatter.cs#L127-L131
                content.DeclaredType = content.Value.GetType();
            }

            base.OnActionExecuted(actionExecutedContext);
        }

        private static bool IsSuccessStatusCode(int statusCode)
        {
            return statusCode >= 200 && statusCode < 300;
        }
    }

OData query examples:

	http://localhost:<port>/opstenant?$top=5&$expand=Buildings&$filter=Name eq 'One'&$orderby=Name desc
	http://localhost:<port>/opstenant?$top=5&$expand=Buildings&$filter=Name ne 'One'&$orderby=Name desc
	http://localhost:<port>/opstenant?$filter=Name eq 'One'
	http://localhost:<port>/opstenant?$top=5&$expand=Buildings&$orderby=Name desc
	http://localhost:<port>/opstenant?$orderby=Name desc
	http://localhost:<port>/opstenant?$orderby=Name desc&$count=true
	http://localhost:<port>/opstenant?$top=5&$filter=Name eq 'One'&$orderby=Name desc&$count=true
	http://localhost:<port>/opstenant?$top=5&$select=Name, Identity
	http://localhost:<port>/opstenant?$top=5&$expand=Buildings&$filter=Name ne 'One'&$orderby=Name desc
	http://localhost:<port>/opstenant?$top=5&$expand=Buildings($expand=Builder($expand=City))&$filter=Name ne 'One'&$orderby=Name desc
	http://localhost:<port>/opstenant?$top=5&$select=Buildings,Name&$expand=Buildings($select=Name,Builder;$expand=Builder($select=Name,City;$expand=City))&$filter=Name ne 'One'&$orderby=Name desc

	http://localhost:<port>/corebuilding?$top=5&$expand=Builder,Tenant&$filter=name ne 'One L1'&$orderby=Name desc
	http://localhost:<port>/corebuilding?$top=5&$expand=Builder($expand=City),Tenant&$filter=name ne 'One L2'&$orderby=Name desc