基于 abp vNext 和 .NET Core 开发博客项目

上一篇文章完成了项目的全局异常处理和日志记录。

在日志记录中使用的静态方法有人指出写法不是很优雅，遂优化一下上一篇中日志记录的方法，具体操作如下：

在.ToolKits层中新建扩展方法Log4NetExtensions.cs。

//Log4NetExtensions.cs
using log4net;
using log4net.Config;
using Microsoft.Extensions.Hosting;
using System.IO;
using System.Reflection;namespace Meowv.Blog.ToolKits.Extensions
{public static class Log4NetExtensions{public static IHostBuilder UseLog4Net(this IHostBuilder hostBuilder){var log4netRepository = LogManager.GetRepository(Assembly.GetEntryAssembly());XmlConfigurator.Configure(log4netRepository, new FileInfo("log4net.config"));return hostBuilder;}}
}

配置log4net，然后我们直接返回IHostBuilder对象，便于在Main方法中链式调用。

//Program.cs
using Meowv.Blog.ToolKits.Extensions;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Hosting;
using System.Threading.Tasks;namespace Meowv.Blog.HttpApi.Hosting
{public class Program{public static async Task Main(string[] args){await Host.CreateDefaultBuilder(args).UseLog4Net().ConfigureWebHostDefaults(builder =>{builder.UseIISIntegration().UseStartup<Startup>();}).UseAutofac().Build().RunAsync();}}
}

然后修改MeowvBlogExceptionFilter过滤器，代码如下：

//MeowvBlogExceptionFilter.cs
using log4net;
using Microsoft.AspNetCore.Mvc.Filters;namespace Meowv.Blog.HttpApi.Hosting.Filters
{public class MeowvBlogExceptionFilter : IExceptionFilter{private readonly ILog _log;public MeowvBlogExceptionFilter(){_log = LogManager.GetLogger(typeof(MeowvBlogExceptionFilter));}/// <summary>/// 异常处理/// </summary>/// <param name="context"></param>/// <returns></returns>public void OnException(ExceptionContext context){// 错误日志记录_log.Error($"{context.HttpContext.Request.Path}|{context.Exception.Message}", context.Exception);}}
}

可以删掉之前添加的LoggerHelper.cs类，运行一下，同样可以达到预期效果。

本篇将集成Redis，使用Redis来缓存数据，使用方法参考的微软官方文档：https://docs.microsoft.com/zh-cn/aspnet/core/performance/caching/distributed

关于Redis的介绍这里就不多说了，这里有一篇快速入门的文章：Redis快速入门及使用，对于不了解的同学可以看看。

直入主题，先在appsettings.json配置Redis的连接字符串。

//appsettings.json
..."Caching": {"RedisConnectionString": "127.0.0.1:6379,password=123456,ConnectTimeout=15000,SyncTimeout=5000"}
...

对应的，在AppSettings.cs中读取。

//AppSettings.cs
.../// <summary>/// Caching/// </summary>public static class Caching{/// <summary>/// RedisConnectionString/// </summary>public static string RedisConnectionString => _config["Caching:RedisConnectionString"];}
...

在.Application.Caching层添加包Microsoft.Extensions.Caching.StackExchangeRedis，然后在模块类MeowvBlogApplicationCachingModule中添加配置缓存实现。

//MeowvBlogApplicationCachingModule.cs
using Meowv.Blog.Domain;
using Meowv.Blog.Domain.Configurations;
using Microsoft.Extensions.DependencyInjection;
using Volo.Abp.Caching;
using Volo.Abp.Modularity;namespace Meowv.Blog.Application.Caching
{[DependsOn(typeof(AbpCachingModule),typeof(MeowvBlogDomainModule))]public class MeowvBlogApplicationCachingModule : AbpModule{public override void ConfigureServices(ServiceConfigurationContext context){context.Services.AddStackExchangeRedisCache(options =>{options.Configuration = AppSettings.Caching.RedisConnectionString;//options.InstanceName//options.ConfigurationOptions});}}
}

options.Configuration是 Redis 的连接字符串。

options.InstanceNam是 Redis 实例名称，这里没填。

options.ConfigurationOptions是 Redis 的配置属性，如果配置了这个字，将优先于 Configuration 中的配置，同时它支持更多的选项。我这里也没填。

紧接着我们就可以直接使用了，直接将IDistributedCache接口依赖关系注入即可。

可以看到默认已经实现了这么多常用的接口，已经够我这个小项目用的了，同时在Microsoft.Extensions.Caching.Distributed.DistributedCacheExtensions中微软还给我们提供了很多扩展方法。

于是，我们我就想到写一个新的扩展方法，可以同时处理获取和添加缓存的操作，当缓存存在时，直接返回，不存在时，添加缓存。

新建MeowvBlogApplicationCachingExtensions.cs扩展方法，如下：

//MeowvBlogApplicationCachingExtensions.cs
using Meowv.Blog.ToolKits.Extensions;
using Microsoft.Extensions.Caching.Distributed;
using System;
using System.Threading.Tasks;namespace Meowv.Blog.Application.Caching
{public static class MeowvBlogApplicationCachingExtensions{/// <summary>/// 获取或添加缓存/// </summary>/// <typeparam name="TCacheItem"></typeparam>/// <param name="cache"></param>/// <param name="key"></param>/// <param name="factory"></param>/// <param name="minutes"></param>/// <returns></returns>public static async Task<TCacheItem> GetOrAddAsync<TCacheItem>(this IDistributedCache cache, string key, Func<Task<TCacheItem>> factory, int minutes){TCacheItem cacheItem;var result = await cache.GetStringAsync(key);if (string.IsNullOrEmpty(result)){cacheItem = await factory.Invoke();var options = new DistributedCacheEntryOptions();if (minutes != CacheStrategy.NEVER){options.AbsoluteExpiration = DateTimeOffset.Now.AddMinutes(minutes);}await cache.SetStringAsync(key, cacheItem.ToJson(), options);}else{cacheItem = result.FromJson<TCacheItem>();}return cacheItem;}}
}

我们可以在DistributedCacheEntryOptions中可以配置我们的缓存过期时间，其中有一个判断条件，就是当minutes = -1的时候，不指定过期时间，那么我们的缓存就不会过期了。

GetStringAsync()、SetStringAsync()是DistributedCacheExtensions的扩展方法，最终会将缓存项cacheItem转换成JSON格式进行存储。

CacheStrategy是在.Domain.Shared层定义的缓存过期时间策略常量。

//MeowvBlogConsts.cs
.../// <summary>/// 缓存过期时间策略/// </summary>public static class CacheStrategy{/// <summary>/// 一天过期24小时/// </summary>public const int ONE_DAY = 1440;/// <summary>/// 12小时过期/// </summary>public const int HALF_DAY = 720;/// <summary>/// 8小时过期/// </summary>public const int EIGHT_HOURS = 480;/// <summary>/// 5小时过期/// </summary>public const int FIVE_HOURS = 300;/// <summary>/// 3小时过期/// </summary>public const int THREE_HOURS = 180;/// <summary>/// 2小时过期/// </summary>public const int TWO_HOURS = 120;/// <summary>/// 1小时过期/// </summary>public const int ONE_HOURS = 60;/// <summary>/// 半小时过期/// </summary>public const int HALF_HOURS = 30;/// <summary>/// 5分钟过期/// </summary>public const int FIVE_MINUTES = 5;/// <summary>/// 1分钟过期/// </summary>public const int ONE_MINUTE = 1;/// <summary>/// 永不过期/// </summary>public const int NEVER = -1;}
...

接下来去创建缓存接口类和实现类，然后再我们的引用服务层.Application中进行调用，拿上一篇中接入GitHub的几个接口来做新增缓存操作。

和.Application层格式一样，在.Application.Caching中新建Authorize文件夹，添加缓存接口IAuthorizeCacheService和实现类AuthorizeCacheService。

注意命名规范，实现类肯定要继承一个公共的CachingServiceBase基类。在.Application.Caching层根目录添加MeowvBlogApplicationCachingServiceBase.cs，继承ITransientDependency。

//MeowvBlogApplicationCachingServiceBase.cs
using Microsoft.Extensions.Caching.Distributed;
using Volo.Abp.DependencyInjection;namespace Meowv.Blog.Application.Caching
{public class CachingServiceBase : ITransientDependency{public IDistributedCache Cache { get; set; }}
}

然后使用属性注入的方式，注入IDistributedCache。这样我们只要继承了基类：CachingServiceBase，就可以愉快的使用缓存了。

添加要缓存的接口到IAuthorizeCacheService，在这里我们使用Func()方法，我们的接口返回什么类型由Func()来决定，于是添加三个接口如下：

//IAuthorizeCacheService.cs
using Meowv.Blog.ToolKits.Base;
using System;
using System.Threading.Tasks;namespace Meowv.Blog.Application.Caching.Authorize
{public interface IAuthorizeCacheService{/// <summary>/// 获取登录地址(GitHub)/// </summary>/// <returns></returns>Task<ServiceResult<string>> GetLoginAddressAsync(Func<Task<ServiceResult<string>>> factory);/// <summary>/// 获取AccessToken/// </summary>/// <param name="code"></param>/// <param name="factory"></param>/// <returns></returns>Task<ServiceResult<string>> GetAccessTokenAsync(string code, Func<Task<ServiceResult<string>>> factory);/// <summary>/// 登录成功，生成Token/// </summary>/// <param name="access_token"></param>/// <param name="factory"></param>/// <returns></returns>Task<ServiceResult<string>> GenerateTokenAsync(string access_token, Func<Task<ServiceResult<string>>> factory);}
}

是不是和IAuthorizeService代码很像，的确，我就是直接复制过来改的。

在AuthorizeCacheService中实现接口。

//AuthorizeCacheService.cs
using Meowv.Blog.ToolKits.Base;
using Meowv.Blog.ToolKits.Extensions;
using System;
using System.Threading.Tasks;
using static Meowv.Blog.Domain.Shared.MeowvBlogConsts;namespace Meowv.Blog.Application.Caching.Authorize.Impl
{public class AuthorizeCacheService : CachingServiceBase, IAuthorizeCacheService{private const string KEY_GetLoginAddress = "Authorize:GetLoginAddress";private const string KEY_GetAccessToken = "Authorize:GetAccessToken-{0}";private const string KEY_GenerateToken = "Authorize:GenerateToken-{0}";/// <summary>/// 获取登录地址(GitHub)/// </summary>/// <param name="factory"></param>/// <returns></returns>public async Task<ServiceResult<string>> GetLoginAddressAsync(Func<Task<ServiceResult<string>>> factory){return await Cache.GetOrAddAsync(KEY_GetLoginAddress, factory, CacheStrategy.NEVER);}/// <summary>/// 获取AccessToken/// </summary>/// <param name="code"></param>/// <param name="factory"></param>/// <returns></returns>public async Task<ServiceResult<string>> GetAccessTokenAsync(string code, Func<Task<ServiceResult<string>>> factory){return await Cache.GetOrAddAsync(KEY_GetAccessToken.FormatWith(code), factory, CacheStrategy.FIVE_MINUTES);}/// <summary>/// 登录成功，生成Token/// </summary>/// <param name="access_token"></param>/// <param name="factory"></param>/// <returns></returns>public async Task<ServiceResult<string>> GenerateTokenAsync(string access_token, Func<Task<ServiceResult<string>>> factory){return await Cache.GetOrAddAsync(KEY_GenerateToken.FormatWith(access_token), factory, CacheStrategy.ONE_HOURS);}}
}

代码很简单，每个缓存都有固定KEY值，根据参数生成KEY，然后调用前面写的扩展方法，再给一个过期时间即可，可以看到KEY里面包含了冒号 :，这个冒号 : 可以起到类似于文件夹的操作，在界面化管理工具中可以很友好的查看。

这样我们的缓存就搞定了，然后在.Application层对应的Service中进行调用。代码如下：

//AuthorizeService.cs
using Meowv.Blog.Application.Caching.Authorize;
using Meowv.Blog.Domain.Configurations;
using Meowv.Blog.ToolKits.Base;
using Meowv.Blog.ToolKits.Extensions;
using Meowv.Blog.ToolKits.GitHub;
using Microsoft.IdentityModel.Tokens;
using System;
using System.IdentityModel.Tokens.Jwt;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Security.Claims;
using System.Threading.Tasks;namespace Meowv.Blog.Application.Authorize.Impl
{public class AuthorizeService : ServiceBase, IAuthorizeService{private readonly IAuthorizeCacheService _authorizeCacheService;private readonly IHttpClientFactory _httpClient;public AuthorizeService(IAuthorizeCacheService authorizeCacheService,IHttpClientFactory httpClient){_authorizeCacheService = authorizeCacheService;_httpClient = httpClient;}/// <summary>/// 获取登录地址(GitHub)/// </summary>/// <returns></returns>public async Task<ServiceResult<string>> GetLoginAddressAsync(){return await _authorizeCacheService.GetLoginAddressAsync(async () =>{var result = new ServiceResult<string>();var request = new AuthorizeRequest();var address = string.Concat(new string[]{GitHubConfig.API_Authorize,"?client_id=", request.Client_ID,"&scope=", request.Scope,"&state=", request.State,"&redirect_uri=", request.Redirect_Uri});result.IsSuccess(address);return await Task.FromResult(result);});}/// <summary>/// 获取AccessToken/// </summary>/// <param name="code"></param>/// <returns></returns>public async Task<ServiceResult<string>> GetAccessTokenAsync(string code){var result = new ServiceResult<string>();if (string.IsNullOrEmpty(code)){result.IsFailed("code为空");return result;}return await _authorizeCacheService.GetAccessTokenAsync(code, async () =>{var request = new AccessTokenRequest();var content = new StringContent($"code={code}&client_id={request.Client_ID}&redirect_uri={request.Redirect_Uri}&client_secret={request.Client_Secret}");content.Headers.ContentType = new MediaTypeHeaderValue("application/x-www-form-urlencoded");using var client = _httpClient.CreateClient();var httpResponse = await client.PostAsync(GitHubConfig.API_AccessToken, content);var response = await httpResponse.Content.ReadAsStringAsync();if (response.StartsWith("access_token"))result.IsSuccess(response.Split("=")[1].Split("&").First());elseresult.IsFailed("code不正确");return result;});}/// <summary>/// 登录成功，生成Token/// </summary>/// <param name="access_token"></param>/// <returns></returns>public async Task<ServiceResult<string>> GenerateTokenAsync(string access_token){var result = new ServiceResult<string>();if (string.IsNullOrEmpty(access_token)){result.IsFailed("access_token为空");return result;}return await _authorizeCacheService.GenerateTokenAsync(access_token, async () =>{var url = $"{GitHubConfig.API_User}?access_token={access_token}";using var client = _httpClient.CreateClient();client.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.14 Safari/537.36 Edg/83.0.478.13");var httpResponse = await client.GetAsync(url);if (httpResponse.StatusCode != HttpStatusCode.OK){result.IsFailed("access_token不正确");return result;}var content = await httpResponse.Content.ReadAsStringAsync();var user = content.FromJson<UserResponse>();if (user.IsNull()){result.IsFailed("未获取到用户数据");return result;}if (user.Id != GitHubConfig.UserId){result.IsFailed("当前账号未授权");return result;}var claims = new[] {new Claim(ClaimTypes.Name, user.Name),new Claim(ClaimTypes.Email, user.Email),new Claim(JwtRegisteredClaimNames.Exp, $"{new DateTimeOffset(DateTime.Now.AddMinutes(AppSettings.JWT.Expires)).ToUnixTimeSeconds()}"),new Claim(JwtRegisteredClaimNames.Nbf, $"{new DateTimeOffset(DateTime.Now).ToUnixTimeSeconds()}")};var key = new SymmetricSecurityKey(AppSettings.JWT.SecurityKey.SerializeUtf8());var creds = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);var securityToken = new JwtSecurityToken(issuer: AppSettings.JWT.Domain,audience: AppSettings.JWT.Domain,claims: claims,expires: DateTime.Now.AddMinutes(AppSettings.JWT.Expires),signingCredentials: creds);var token = new JwtSecurityTokenHandler().WriteToken(securityToken);result.IsSuccess(token);return await Task.FromResult(result);});}}
}

直接return我们的缓存接口，当查询到Redis中存在KEY值的缓存就不会再走我们的具体的实现方法了。

注意注意，千万不要忘了在.Application层的模块类中添加依赖缓存模块MeowvBlogApplicationCachingModule，不然就会报错报错报错(我就是忘了添加...)

//MeowvBlogApplicationCachingModule.cs
using Meowv.Blog.Domain;
using Meowv.Blog.Domain.Configurations;
using Microsoft.Extensions.DependencyInjection;
using Volo.Abp.Caching;
using Volo.Abp.Modularity;namespace Meowv.Blog.Application.Caching
{[DependsOn(typeof(AbpCachingModule),typeof(MeowvBlogDomainModule))]public class MeowvBlogApplicationCachingModule : AbpModule{public override void ConfigureServices(ServiceConfigurationContext context){context.Services.AddStackExchangeRedisCache(options =>{options.Configuration = AppSettings.Caching.RedisConnectionString;});}}
}

此时项目的层级目录结构。