Passing OData query options in request body

Applies To:# OData WebApi v7.5 for .NET Core OData AspNetCore WebApi V7.5# OData WebApi v7.5 for .NET FX OData AspNet WebApi V7.5

The query options part of an OData URL can be quite long, potentially exceeding the maximum length that many hosting environments (including IIS) impose. This can limit the client's ability to request the exact set of data they are interested in, especially when using explict select statements.

OData WebApi V7.5 introduced support for passing query options in the request body. You append /query to the resource path of the URL, use the POST verb instead of GET, and pass the query options part of the URL in the request body.

Example

POST: http://ServiceRoot/Movies/$query
Content-Type: text/plain
Body: $select=Id,Name,Classification,RunningTime&$filter=contains(Name,%20%27li%27)&$orderby=Name%20desc

In the rest of this page, we demonstrate how this feature works by building a simple OData service

1. Create the Project

Create a new C# project from the ASP.NET Core Web Application template

• .NET Core platform
• ASP.NET Core 3.1 runtime
• Empty project template
• Uncheck Configure for HTTPS option

2. Install Packages

Install OData AspNetCore WebApi package. Using Package Manager Console:

Install-Package Microsoft.AspNetCore.OData -Version 7.5.0

Note: You can also install any higher version

3. Define CLR Type

public class Movie
{
	[Key]
	public int Id { get; set; }
	public string Name { get; set; }
	public string Classification { get; set; }
	public int RunningTime { get; set; }
}

4. Configure the Service

public class Startup
{
	public void ConfigureServices(IServiceCollection services)
	{
		services.AddMvc(options => options.EnableEndpointRouting = false)
				.SetCompatibilityVersion(CompatibilityVersion.Version_3_0);
		services.AddOData();
	}

	public void Configure(IApplicationBuilder app)
	{
		var modelBuilder = new ODataConventionModelBuilder();
		modelBuilder.EntitySet<Movie>("Movies");

		app.UseMvc(routeBuilder =>
		{
			routeBuilder.Select().Filter().Expand().Count().OrderBy().SkipToken().MaxTop(100);
			routeBuilder.MapODataServiceRoute(
				routeName: "odata",
				routePrefix: "odata",
				model: modelBuilder.GetEdmModel());
		});
	}
}

5. Add controller

public class MoviesController : ODataController
{
	static readonly List<Movie> Movies;

	static MoviesController()
	{
		Movies = new List<Movie>
		{
			new Movie { Id = 1, Name = "Bombshell", Classification = "R", RunningTime = 108 },
			new Movie { Id = 2, Name = "Ad Astra", Classification = "PG-13", RunningTime = 124 },
			new Movie { Id = 3, Name = "Dolittle", Classification = "PG", RunningTime = 101 },
			new Movie { Id = 4, Name = "Doctor Strange", Classification = "PG-13", RunningTime = 115 },
			new Movie { Id = 5, Name = "The Equalizer", Classification = "R", RunningTime = 132 }
		};
	}

	[EnableQuery]
	public List<Movie> Get()
	{
		return Movies;
	}
}

6. Pass query options in request body

Using an API client such as Postman, send a POST request to http://localhost:PORT/odata/Movies/$query.

• Set Content-Type header to text/plain
• Set request body to $filter=contains(Name,'li')&$orderby=Name desc&$select=Id,Name,Classification,RunningTime

You should get the following response:

{
    "@odata.context": "http://localhost:PORT/odata/$metadata#Movies(Id,Name,Classification,RunningTime)",
    "value": [
        {
            "Id": 5,
            "Name": "The Equalizer",
            "Classification": "R",
            "RunningTime": 132
        },
        {
            "Id": 3,
            "Name": "Dolittle",
            "Classification": "PG",
            "RunningTime": 101
        }
    ]
}

The feature also allows you split the query options between the request body and the request URL.

Example

POST: http://ServiceRoot/Movies/$query?$orderby=Name%20desc
Content-Type: text/plain
Body: $filter=contains(Name,'li')&$select=Id,Name,Classification,RunningTime

You can visit this page to learn how you can implement and plug in a custom parser for query options in the request body.