|
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using Microsoft.Extensions.Primitives;
namespace Microsoft.AspNetCore.HeaderPropagation;
/// <summary>
/// Define the configuration of a header for the <see cref="HeaderPropagationMiddleware"/>.
/// </summary>
public class HeaderPropagationEntry
{
/// <summary>
/// Creates a new <see cref="HeaderPropagationEntry"/> with the provided <paramref name="inboundHeaderName"/>,
/// <paramref name="capturedHeaderName"/> and <paramref name="valueFilter"/>.
/// </summary>
/// <param name="inboundHeaderName">
/// The name of the header to be captured by <see cref="HeaderPropagationMiddleware"/>.
/// </param>
/// <param name="capturedHeaderName">
/// The name of the header to be added by <see cref="HeaderPropagationMessageHandler"/>.
/// </param>
/// <param name="valueFilter">
/// A filter delegate that can be used to transform the header value. May be null.
/// </param>
public HeaderPropagationEntry(
string inboundHeaderName,
string capturedHeaderName,
Func<HeaderPropagationContext, StringValues>? valueFilter)
{
ArgumentNullException.ThrowIfNull(inboundHeaderName);
ArgumentNullException.ThrowIfNull(capturedHeaderName);
InboundHeaderName = inboundHeaderName;
CapturedHeaderName = capturedHeaderName;
ValueFilter = valueFilter; // May be null
}
/// <summary>
/// Gets the name of the header that will be captured by the <see cref="HeaderPropagationMiddleware"/>.
/// </summary>
public string InboundHeaderName { get; }
/// <summary>
/// Gets the name of the header to be used by default by the <see cref="HeaderPropagationMessageHandler"/> for the
/// outbound http requests.
/// </summary>
public string CapturedHeaderName { get; }
/// <summary>
/// Gets or sets a filter delegate that can be used to transform the header value.
/// </summary>
/// <remarks>
/// <para>
/// When present, the delegate will be evaluated once per request to provide the transformed
/// header value. The delegate will be called regardless of whether a header with the name
/// corresponding to <see cref="InboundHeaderName"/> is present in the request. If the result
/// of evaluating <see cref="ValueFilter"/> is null or empty, it will not be added to the propagated
/// values.
/// </para>
/// </remarks>
public Func<HeaderPropagationContext, StringValues>? ValueFilter { get; }
}
|