Table of Contents

Class HttpResponseExtensions

Namespace
Cuemon.Extensions.AspNetCore.Http
Assembly
Cuemon.Extensions.AspNetCore.dll

Extension methods for the HttpResponse class.

public static class HttpResponseExtensions
Inheritance
HttpResponseExtensions

Examples

HttpResponseExtensions provides extension methods for HttpResponse to manage ETag and Last-Modified headers, write response bodies asynchronously, and transform HttpResponseMessage content into the ASP.NET Core response pipeline. This example calls AddOrUpdateEntityTagHeader with a ChecksumBuilder for ETag generation, AddOrUpdateLastModifiedHeader with a 2024-06-15T10:00:00Z UTC date, WriteBodyAsync with a byte array delegate, and OnStartingInvokeTransformer to transfer an HttpResponseMessage with status 200 OK and JSON content type. Each operation is demonstrated independently, with Console output confirming the header values and response modifications.

using System;
using System.Net;
using System.Net.Http;
using System.Threading.Tasks;
using Cuemon.Data.Integrity;
using Cuemon.Extensions.AspNetCore.Http;
using Cuemon.Security;
using Microsoft.AspNetCore.Http;

namespace MyApp.AspNetCore.Http
{
    public class HttpResponseExtensionsExample
    {
        public async Task DemonstrateAsync(HttpResponse response, HttpRequest request)
        {
            // Add or update an ETag header using a checksum builder
            var builder = new ChecksumBuilder(() => HashFactory.CreateFnv128());
            response.AddOrUpdateEntityTagHeader(request, builder, isWeak: false);
            // Response now has ETag: "..." header

            // Add or update a Last-Modified header with a specific date
            var lastModified = new DateTime(2024, 6, 15, 10, 0, 0, DateTimeKind.Utc);
            response.AddOrUpdateLastModifiedHeader(request, lastModified);
            // Response now has Last-Modified: "Sat, 15 Jun 2024 10:00:00 GMT" header

            // Write bytes to the response body from a delegate
            await response.WriteBodyAsync(() => new byte[] { 0x48, 0x65, 0x6C, 0x6C, 0x6F });
            // Response body now contains "Hello"

            // Transfer a HttpResponseMessage to the response pipeline
            var message = new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = new StringContent("{\"status\":\"ok\"}")
            };
            response.OnStartingInvokeTransformer(message, (msg, resp) =>
            {
                resp.StatusCode = (int)msg.StatusCode;
                resp.Headers["Content-Type"] = "application/json";
            });
            // The response will send the transformed content when the pipeline starts

}}
}

Methods

AddOrUpdateEntityTagHeader(HttpResponse, HttpRequest, ChecksumBuilder, bool)

Attempts to add or update the necessary HTTP response headers needed to provide entity tag header information.

public static void AddOrUpdateEntityTagHeader(this HttpResponse response, HttpRequest request, ChecksumBuilder builder, bool isWeak = false)

Parameters

response HttpResponse

The HttpResponse to extend.

request HttpRequest

An instance of the HttpRequest object.

builder ChecksumBuilder

A ChecksumBuilder that represents the integrity of the client.

isWeak bool

A value that indicates if this entity-tag header is a weak validator.

Exceptions

ArgumentNullException

response cannot be null -or- request cannot be null -or- builder cannot be null.

AddOrUpdateLastModifiedHeader(HttpResponse, HttpRequest, DateTime)

Attempts to add or update the necessary HTTP response headers needed to provide last-modified information.

public static void AddOrUpdateLastModifiedHeader(this HttpResponse response, HttpRequest request, DateTime lastModified)

Parameters

response HttpResponse

The HttpResponse to extend.

request HttpRequest

An instance of the HttpRequest object.

lastModified DateTime

A value that represents when the resource was either created or last modified.

Exceptions

ArgumentNullException

response cannot be null -or- request cannot be null.

OnStartingInvokeTransformer(HttpResponse, HttpResponseMessage, Action<HttpResponseMessage, HttpResponse>)

Transfers the specified message to the HTTP response pipeline using the transformer delegate.

public static void OnStartingInvokeTransformer(this HttpResponse response, HttpResponseMessage message, Action<HttpResponseMessage, HttpResponse> transformer)

Parameters

response HttpResponse

The HttpResponse to extend.

message HttpResponseMessage

The HttpResponseMessage to convert into an HTTP equivalent HttpResponse.

transformer Action<HttpResponseMessage, HttpResponse>

The delegate that converts a HttpResponseMessage to an HTTP equivalent HttpResponse.

WriteBodyAsync(HttpResponse, Func<byte[]>)

Asynchronously writes a sequence of bytes to the response body stream and advances the current position within this stream by the number of bytes written.

public static Task WriteBodyAsync(this HttpResponse response, Func<byte[]> body)

Parameters

response HttpResponse

The HttpResponse to extend.

body Func<byte[]>

The function delegate that resolves the bytes to write.

Returns

Task

A task that represents the asynchronous write operation.

Edit this page