WebAPI ODATA without Entity Framework

Question

Consider the following method in a Web Api controller:

[Queryable(AllowedQueryOptions= AllowedQueryOptions.All)]
public override IQueryable<Mandate> Get()
{
        return new List<Mandate>() { new Mandate() { 
            Id = 1, 
            PolicyNumber = "350000000",
            OpenPositions = new List<OpenPosition>(){ 
                new OpenPosition(){ Id = 1, Amount =2300 },
                new OpenPosition(){ Id = 2, Amount =2100 }
            }},
            new Mandate() { 
                Id = 2, 
                PolicyNumber = "240000000" ,
                OpenPositions = new List<OpenPosition>(){ 
                new OpenPosition(){ Id = 3, Amount =2500 },
                new OpenPosition(){ Id = 2, Amount =2100 }
            }

            } }.AsQueryable<Mandate>();
    }

Here the list is built manually and if I browse to the following url:

http://localhost:52446/odata/Mandates?$filter=Id eq 1 it returns the correct item from the list.

Now obviously the list is more likely to be a database structure. Data would be retrieved using some ORM and returned to the Web API service.

I don't use Entity Framework (and I can't because of legacy systems).

How would I use Web API in this case? How would I translate the url parameters so that the filters are applied by the layer responsible of the data access?

If there is no LINQ provider for your database, you would need to translate the ODataQueryOptions. Start with this blog post: blogs.msdn.com/b/webdev/archive/2013/02/25/… — Mike Wasson
Got it. You pointed me into the right direction with your LINQ provider. I found out I can do it easily with the ORM we are using (OpenAccess). More info here : documentation.telerik.com/openaccess-orm/developers-guide/… — Sam
@Sam could you post your comment as answer? Otherwise the questions seems like active even though it is resolved. — Sebastian K

Sam Sam · Accepted Answer · 2015-03-17T07:48:09

Got it. You pointed me into the right direction with your LINQ provider. I found out I can do it easily with the ORM we are using (OpenAccess). More info here :http://docs.telerik.com/data-access/developers-guide/using-web-services/asp.net-web-api/developer-guide-wcfservices-web-api-expose-oacontext

WebAPI ODATA without Entity Framework

1 Answers