ASP.NET Core – How to receive requests with XML content

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Receiving requests with XML content is straightforward. You have to register the built-in XML InputFormatter (otherwise you get 415 – Unsupported Media Type errors). When a request comes in with an XML Content-Type (such as application/xml), it uses this InputFormatter to deserialize the request body XML.

In this article, I’ll show step-by-step how to receive a request with XML by registering the built-in XML InputFormatter, adding a model class, and configuring the action method.

Note: There are actually two XML InputFormatters to pick from. One that uses XmlSerializer and one that uses DataContractSerializer. I prefer XmlSerializer since it’s easier to use.

1 – Register the XML InputFormatter

In the initialization code, call AddXmlSerializerFormatters() to register the built-in XML InputFormatter:

using Microsoft.Extensions.DependencyInjection;

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddControllers().AddXmlSerializerFormatters();

//the rest of the initialization code
Code language: C# (cs)

This essentially adds the built-in XmlSerializerInputFormatter class to the collection of InputFormatters. Note: It also adds the XML output formatter, which you need for returning XML responses.

2 – Add a model class

Add a model class that matches the XML structure:

public class Recipe
{
	public string Name { get; set; }
	public int Servings { get; set; }
}
Code language: C# (cs)

Note: Property order doesn’t matter when you use XmlSerializer and no attributes are required.

3 – Configure the action method

Now add the model class as a parameter on the action method and optionally add the [Consumes] attribute:

[HttpPost()]
[Consumes("application/xml")] //OPTIONAL: this constrains it to only allow XML
public IActionResult Post(Recipe recipe)
{
	return Ok($"Posted recipe {recipe.Name}");
}
Code language: C# (cs)

The Recipe is a complex type, so it’s implicitly bound to the request body (don’t need to annotate it with [FromBody]).

Note: You don’t need to add [Consumes(“application/xml”)] to get it to work with XML. This attribute is used to constrain the allowed Content-Types. If you don’t add this, the client can actually send the request as either JSON or XML, so it’s more flexible.

Example of sending an XML request

Here’s an example of sending an XML request to the action method shown above:

POST /Recipe

Content-Type: application/xml

Body:
<Recipe>
    <Name>Pizza</Name>
    <Servings>4</Servings>
</Recipe>Code language: plaintext (plaintext)

Because the XML InputFormatter is registered, it’s able to deserialize the XML request body. This returns a 200 (OK) response with the following output:

Posted recipe PizzaCode language: plaintext (plaintext)

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