# RequestHeadersTransformExtensions

- Kind: `class`
- Package: [Aspire.Hosting.Yarp](/reference/api/csharp/aspire.hosting.yarp.md)
- Version: `13.4.0`
- Namespace: `Aspire.Hosting.Yarp.Transforms`
- Target framework: `net8.0`
- Source: [GitHub](https://github.com/microsoft/aspire/blob/cbc352350f1a9bafbaff10d14a2c8de4ac186a48/src/Aspire.Hosting.Yarp/ConfigurationBuilder/Transforms/RequestHeadersTransformExtensions.cs)

Extensions for adding request header transforms.

## Definition

```csharp
namespace Aspire.Hosting.Yarp.Transforms;

public static class RequestHeadersTransformExtensions
{
    // ...
}
```

## Methods

- [WithTransformCopyRequestHeaders(YarpRoute, bool)](/reference/api/csharp/aspire.hosting.yarp/requestheaderstransformextensions/methods.md#withtransformcopyrequestheaders-yarproute-bool) : [YarpRoute](/reference/api/csharp/aspire.hosting.yarp/yarproute.md) `extension` `ats export` -- Adds the transform which will enable or suppress copying request headers to the proxy request.
- [WithTransformRequestHeader(YarpRoute, string, string, bool)](/reference/api/csharp/aspire.hosting.yarp/requestheaderstransformextensions/methods.md#withtransformrequestheader-yarproute-string-string-bool) : [YarpRoute](/reference/api/csharp/aspire.hosting.yarp/yarproute.md) `extension` `ats export` -- Adds the transform which will append or set the request header.
- [WithTransformRequestHeaderRemove(YarpRoute, string)](/reference/api/csharp/aspire.hosting.yarp/requestheaderstransformextensions/methods.md#withtransformrequestheaderremove-yarproute-string) : [YarpRoute](/reference/api/csharp/aspire.hosting.yarp/yarproute.md) `extension` `ats export` -- Adds the transform which will remove the request header.
- [WithTransformRequestHeaderRouteValue(YarpRoute, string, string, bool)](/reference/api/csharp/aspire.hosting.yarp/requestheaderstransformextensions/methods.md#withtransformrequestheaderroutevalue-yarproute-string-string-bool) : [YarpRoute](/reference/api/csharp/aspire.hosting.yarp/yarproute.md) `extension` `ats export` -- Adds the transform which will append or set the request header from a route value.
- [WithTransformRequestHeadersAllowed(YarpRoute, string[])](/reference/api/csharp/aspire.hosting.yarp/requestheaderstransformextensions/methods.md#withtransformrequestheadersallowed-yarproute-string) : [YarpRoute](/reference/api/csharp/aspire.hosting.yarp/yarproute.md) `extension` `ats export` -- Adds the transform which will only copy the allowed request headers. Other transforms that modify or append to existing headers may be affected if not included in the allow list.
- [WithTransformUseOriginalHostHeader(YarpRoute, bool)](/reference/api/csharp/aspire.hosting.yarp/requestheaderstransformextensions/methods.md#withtransformuseoriginalhostheader-yarproute-bool) : [YarpRoute](/reference/api/csharp/aspire.hosting.yarp/yarproute.md) `extension` `ats export` -- Adds the transform which will copy the incoming request Host header to the proxy request.