/// <summary>
/// This method will either add or update the necessary HTTP response headers needed to provide entity tag header information.
/// </summary>
/// <param name="response">The <see cref="HttpResponse"/> to extend.</param>
/// <param name="request">An instance of the <see cref="HttpRequest"/> object.</param>
/// <param name="builder">A <see cref="ChecksumBuilder"/> that represents the integrity of the client.</param>
/// <param name="isWeak">A value that indicates if this entity-tag header is a weak validator.</param>
public static void SetEntityTagHeaderInformation(this HttpResponse response, HttpRequest request, ChecksumBuilder builder, bool isWeak = false)
{
Validator.ThrowIfNull(response, nameof(response));
Validator.ThrowIfNull(request, nameof(request));
Validator.ThrowIfNull(builder, nameof(builder));
builder = builder.CombineWith(request.Headers[HeaderNames.Accept]);
if (response.IsSuccessStatusCode() && request.IsClientSideResourceCached(builder))
{
response.StatusCode = StatusCodes.Status304NotModified;
}
response.Headers.AddOrUpdate(HeaderNames.ETag, new StringValues(builder.ToEntityTag(isWeak).ToString()));
}
/// <summary>
/// This method will either add or update the necessary HTTP response headers needed to provide entity tag header information.
/// </summary>
/// <param name="response">The <see cref="HttpResponse"/> to extend.</param>
/// <param name="request">An instance of the <see cref="HttpRequest"/> object.</param>
/// <param name="builder">A <see cref="ChecksumBuilder"/> that represents the integrity of the client.</param>
/// <param name="isWeak">A value that indicates if this entity-tag header is a weak validator.</param>
public static void SetEntityTagHeaderInformation(this HttpResponse response, HttpRequest request, ChecksumBuilder builder, bool isWeak = false)
{
Validator.ThrowIfNull(response, nameof(response));
Validator.ThrowIfNull(request, nameof(request));
Validator.ThrowIfNull(builder, nameof(builder));
builder = builder.CombineWith(request.Headers["Accept"]);
DateTime utcNow = DateTime.UtcNow;
if (request.IsClientSideResourceCached(builder))
{
response.StatusCode = StatusCodes.Status304NotModified;
}
else
{
response.Headers.AddOrUpdate(HeaderNames.LastModified, new StringValues(utcNow.ToString("R", DateTimeFormatInfo.InvariantInfo)));
}
response.Headers.AddOrUpdate(HeaderNames.ETag, new StringValues(builder.ToEntityTag(isWeak).ToString()));
}