Falcon.SugarApi/Falcon.SugarApi/Swagger/SwaggerBasicAuthMiddleware.cs

using Microsoft.AspNetCore.Http;
using System;
using System.Collections.Generic;
using System.Net;
using System.Net.Http.Headers;
using System.Text;
using System.Threading.Tasks;

namespace Falcon.SugarApi.Swagger
{
    /// <summary>
    /// Swagger接口基础认证
    /// <para>安全认证只对swagger接口页面进行保护</para>
    /// </summary>
    public class SwaggerBasicAuthMiddleware
    {
        /// <summary>
        /// 下一步请求
        /// </summary>
        private readonly RequestDelegate Next;
        /// <summary>
        /// 配置
        /// </summary>
        public SwaggerOptions Options { get; private set; }

        /// <summary>
        /// 构造中间件
        /// </summary>
        /// <param name="next">下一步</param>
        /// <param name="options">配置</param>
        public SwaggerBasicAuthMiddleware(RequestDelegate next,SwaggerOptions options) {
            Next = next;
            this.Options = options;
        }

        /// <summary>
        /// 执行中间件
        /// </summary>
        /// <param name="context">HttpContext</param>
        /// <returns>任务</returns>
        public virtual async Task InvokeAsync(HttpContext context) {
            if(this.Options == null) {
                await ToNext(context);
                return;
            }
            if(!this.Options.UseAuth) {
                await ToNext(context);
                return;
            }
            var protectPaths = new List<string> { };
            var pf = this.Options.Prefix.StartsWith("/") ? this.Options.Prefix : "/" + this.Options.Prefix;
            protectPaths.Add(pf);
            protectPaths.Add(pf + "/index.html");
            if(!protectPaths.Contains(context.Request.Path)) {
                await ToNext(context);
                return;
            }
            string? authHeader = context.Request.Headers["Authorization"];
            if(authHeader == null || !authHeader.StartsWith("Basic ")) {
                needAuth(context);
                return;
            }
            var header = AuthenticationHeaderValue.Parse(authHeader);
            if(header == null || header.Parameter == null) {
                needAuth(context);
                return;
            }
            var inBs = Convert.FromBase64String(header.Parameter);
            var cred = Encoding.UTF8.GetString(inBs).Split(':');
            var (un, pw) = (cred[0], cred[1]);
            //var un = cred[0];
            //var pw = cred[1];
            if(un == this.Options.AuthName && pw == this.Options.AuthPassword) {
                await ToNext(context);
                return;
            }
            needAuth(context);
        }

        /// <summary>
        /// 进入下一个中间件
        /// </summary>
        public virtual async Task ToNext(HttpContext context) {
            await Next.Invoke(context).ConfigureAwait(false);
            return;
        }
        /// <summary>
        /// 需要认证
        /// </summary>
        public virtual void needAuth(HttpContext context) {
            context.Response.Headers["WWW-Authenticate"] = "Basic";
            context.Response.StatusCode = (int)HttpStatusCode.Unauthorized;
        }

    }
}