在.NE6 WebApi中使用分布式缓存Redis

首先安装Redis
https://github.com/MicrosoftArchive/redis/releases

https://github.com/cinience/RedisStudio/releases

Redis 启动和关闭
安装好之后，我们可以通过服务启动和关闭 Redis 了，我们可以查看系统的任务管理器，检查是否启动了 redis-server，下面是 redis-server 的启动和关闭命令：

$ redis-server.exe  --service-start # 启动
$ redis-server.exe  --service-stop # 关闭

使用 cli
确认 redis-server 启动之后，我们可以执行 redis 目录里面的 redis-cli.exe 文件，这样就可以连接上 Redis 了。当然，我们也可以通过命令行 CMD 来链接 Redis。

可以直接进行 Redis 存取了：

$ redis-cli.exe -h 127.0.0.1 -p 6379
127.0.0.1:6379> set firstKey "moyufed"
OK
127.0.0.1:6379> get firstKey
"moyufed"
127.0.0.1:6379>

增加密码
在 Redis 的安装目录中，有 redis.windows.conf ，redis.windows-service.conf 两个文件，我们使用记事本打开（推荐Notepad++），找到需要设置密码的行，可以 Ctrl + F 查找 “requirepass” 的行（大概386行位置），分别设置 Redis 密码（去掉前面的 “#”），例子：

requirepass moyufed

使用 Redis
修改好之后重启 redis-server ，此时连接 Redis 之后进行 Redis 存取需要登录，例子：

Administrator@WIN-1706081829 C:\Users\Administrator
$ redis-server.exe  --service-stop
[42636] 25 Feb 18:42:53.622 # Redis service successfully stopped.

Administrator@WIN-1706081829 C:\Users\Administrator
$ redis-server.exe  --service-start
[38828] 25 Feb 18:42:58.576 # Redis service successfully started.

Administrator@WIN-1706081829 C:\Users\Administrator
$ redis-cli.exe -h 127.0.0.1 -p 6379
127.0.0.1:6379> set firstKey "moyufed"
(error) NOAUTH Authentication required.
127.0.0.1:6379> auth moyufed
OK
127.0.0.1:6379> set firstKey "moyufed"
OK
127.0.0.1:6379> get firstKey
"moyufed"
127.0.0.1:6379>

参考文档
Window配置Redis环境和简单使用：https://www.cnblogs.com/wxjnew/p/9160855.html

Windows下Redis安装配置和使用注意事项：https://www.cnblogs.com/LMJBlogs/p/11550170.html

首先配置.NET6的安装环境

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net6.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.Extensions.Caching.StackExchangeRedis" Version="6.0.4" />
	  <PackageReference Include="Swashbuckle.AspNetCore" Version="6.2.3" />
	  <PackageReference Include="Microsoft.EntityFrameworkCore" Version="6.0.3" />
	  <PackageReference Include="Microsoft.EntityFrameworkCore.Abstractions" Version="6.0.3" />
	  <PackageReference Include="Microsoft.EntityFrameworkCore.Relational" Version="6.0.3" />
	  <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="6.0.3" />
	  <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="6.0.3">
		  <PrivateAssets>all</PrivateAssets>
		  <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
	  </PackageReference>
	  <PackageReference Include="Microsoft.Extensions.Configuration" Version="6.0.1" />
	  <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="6.0.0" />
	  <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="6.0.0" />
	  <PackageReference Include="Microsoft.Extensions.Options" Version="6.0.0" />
	  <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
	  <PackageReference Include="NModbus4.NetCore" Version="2.0.1" />
	  <PackageReference Include="Pomelo.EntityFrameworkCore.MySql" Version="6.0.1" />
  </ItemGroup>

</Project>

配置数据仓库:

public record Book
{
    
	public int Id {
     get; set; }
	public string Name {
     get; set; }
	public double Price {
     get; set; }
}

using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata.Builders;

class BookConfig : IEntityTypeConfiguration<Book>
{
    
    public void Configure(EntityTypeBuilder<Book> builder)
    {
    
        builder.ToTable("Books");
        builder.HasKey(x => x.Id);
    }
}

using Microsoft.EntityFrameworkCore;

public class MyDbContext : DbContext
{
    
	private ConfigurationBuilder cfgBuilder = new ConfigurationBuilder();
	private string path = Directory.GetCurrentDirectory();
	public DbSet<Book> Books {
     get; set; }
	public MyDbContext()
	{
    
		//configuration = new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory()).AddJsonFile("Ipcfg.json").Build();
	}
	protected override void OnModelCreating(ModelBuilder modelBuilder)
	{
    
		base.OnModelCreating(modelBuilder);
		modelBuilder.ApplyConfigurationsFromAssembly(this.GetType().Assembly);
	}

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
    
        base.OnConfiguring(optionsBuilder);
		cfgBuilder.AddJsonFile("VariableNode.json", optional: true, reloadOnChange: true);
		IConfigurationRoot configRoot = cfgBuilder.Build();
		string conn = configRoot.GetSection("ConnectionStrings:SqliteConnectionString").Value;
		string connString = "Data Source=" + path + conn;
		optionsBuilder.UseSqlite(connString);
	}
}

{
    
  "ConnectionStrings": {
    
    "SqliteConnectionString": "\\bin\\Debug\\net6.0\\Database\\DbSqlite.db",
    "MySQLConnectionString": "server=192.168.85.102; database=OneToMany; uid=root; pwd=123456;"
  },
  "ModbusNode": {
    
    "Id": 1,
    "NodeClassId": 1,
    "Name": "ModbusTCPClient",
    "Description": "1#ZG上位机测试",
    "ModbusType": "2000",
    "ConnectTimeOut": "2000",
    "CreateTime": "0",
    "ReConnectTime": "5000",
    "IsActive": "True",
    "MaxErrorTimes": "1",
    "KeyWay": "VarName",
    "UseAlarmCheck": "True",
    "ServerURL": "127.0.0.1",
    "Port": "502",
    "DataFormat": "ABCD",
    "VarNum": "6",
    "Type": "ModbusTCP",
    "SlaveID": "1",
    "Length": "10",
    "Start": "0",
    "Variable": [
      {
    
        "Id": 1,
        "Number": "1",
        "Name": "Float1",
        "Description": "40001-40002",
        "Type": "ModbusTCP",
        "VarAddress": 0,
        "Scale": "1",
        "Offset": "0",
        "Start": "0",
        "AccessProperty": "读写",
        "AlarmEnable": "True",
        "ArchiveEnable": "True",
        "SetLimitEnable": "True",
        "AlarmType": "True",
        "DiscreteAlarmType": "False",
        "DiscreteAlarmPriority": "0",
        "DiscreteAlarmNote": "null",
        "LoLoAlarmEnable": "True",
        "LoLoAlarmValue": "0",
        "LoLoAlarmPriority": "0",
        "LoLoAlarmNote": "40001-40002低低报警",
        "LowAlarmEnable": "True",
        "LowAlarmValue": "20",
        "LowAlarmPriority": "0",
        "LowAlarmNote": "40001-40002低报警",
        "HighAlarmEnable": "True",
        "HighAlarmValue": "80",
        "HighAlarmPriority": "0",
        "HighAlarmNote": "40001-40002高报警",
        "HiHiAlarmEnable": "True",
        "HiHiAlarmValue": "100",
        "HiHiAlarmPriority": "0",
        "HiHiAlarmNote": "40001-40002高高报警",
        "ArchivePeriod": "80",
        "SetLimitMax": "100",
        "SetLimitMin": "0",
        "VarType": "Float",
        "StoreType": "HoldingRegister4x",
        "InsertTime": "0",
        "Value": "0",
        "ModbusGroupId": 1
      },
      {
    
        "Id": 2,
        "Number": "2",
        "Name": "Float2",
        "Description": "40003-40004",
        "Type": "ModbusTCP",
        "VarAddress": 2,
        "Scale": "1",
        "Offset": "0",
        "Start": "0",
        "AccessProperty": "读写",
        "AlarmEnable": "True",
        "ArchiveEnable": "True",
        "SetLimitEnable": "True",
        "AlarmType": "True",
        "DiscreteAlarmType": "False",
        "DiscreteAlarmPriority": "0",
        "DiscreteAlarmNote": "null",
        "LoLoAlarmEnable": "True",
        "LoLoAlarmValue": "0",
        "LoLoAlarmPriority": "0",
        "LoLoAlarmNote": "40003-40004低低报警",
        "LowAlarmEnable": "True",
        "LowAlarmValue": "20",
        "LowAlarmPriority": "0",
        "LowAlarmNote": "40003-40004低报警",
        "HighAlarmEnable": "True",
        "HighAlarmValue": "80",
        "HighAlarmPriority": "0",
        "HighAlarmNote": "40003-40004高报警",
        "HiHiAlarmEnable": "True",
        "HiHiAlarmValue": "100",
        "HiHiAlarmPriority": "0",
        "HiHiAlarmNote": "40003-40004高高报警",
        "ArchivePeriod": "80",
        "SetLimitMax": "100",
        "SetLimitMin": "0",
        "VarType": "Float",
        "StoreType": "HoldingRegister4x",
        "InsertTime": "0",
        "Value": "0",
        "ModbusGroupId": 1
      },
      {
    
        "Id": 3,
        "Number": "3",
        "Name": "Float3",
        "Description": "40005-40006",
        "Type": "ModbusTCP",
        "VarAddress": 4,
        "Scale": "1",
        "Offset": "0",
        "Start": "0",
        "AccessProperty": "读写",
        "AlarmEnable": "True",
        "ArchiveEnable": "True",
        "SetLimitEnable": "True",
        "AlarmType": "True",
        "DiscreteAlarmType": "False",
        "DiscreteAlarmPriority": "0",
        "DiscreteAlarmNote": "null",
        "LoLoAlarmEnable": "True",
        "LoLoAlarmValue": "0",
        "LoLoAlarmPriority": "0",
        "LoLoAlarmNote": "40005-40006低低报警",
        "LowAlarmEnable": "True",
        "LowAlarmValue": "20",
        "LowAlarmPriority": "0",
        "LowAlarmNote": "40005-40006低报警",
        "HighAlarmEnable": "True",
        "HighAlarmValue": "80",
        "HighAlarmPriority": "0",
        "HighAlarmNote": "40005-40006高报警",
        "HiHiAlarmEnable": "True",
        "HiHiAlarmValue": "100",
        "HiHiAlarmPriority": "0",
        "HiHiAlarmNote": "40005-40006高高报警",
        "ArchivePeriod": "80",
        "SetLimitMax": "100",
        "SetLimitMin": "0",
        "VarType": "Float",
        "StoreType": "HoldingRegister4x",
        "InsertTime": "0",
        "Value": "0",
        "ModbusGroupId": 1
      },
      {
    
        "Id": 4,
        "Number": "4",
        "Name": "Float4",
        "Description": "40007-40008",
        "Type": "ModbusTCP",
        "VarAddress": 6,
        "Scale": "1",
        "Offset": "0",
        "Start": "0",
        "AccessProperty": "读写",
        "AlarmEnable": "True",
        "ArchiveEnable": "True",
        "SetLimitEnable": "True",
        "AlarmType": "True",
        "DiscreteAlarmType": "False",
        "DiscreteAlarmPriority": "0",
        "DiscreteAlarmNote": "null",
        "LoLoAlarmEnable": "True",
        "LoLoAlarmValue": "0",
        "LoLoAlarmPriority": "0",
        "LoLoAlarmNote": "40003-40004低低报警",
        "LowAlarmEnable": "True",
        "LowAlarmValue": "20",
        "LowAlarmPriority": "0",
        "LowAlarmNote": "40003-40004低报警",
        "HighAlarmEnable": "True",
        "HighAlarmValue": "80",
        "HighAlarmPriority": "0",
        "HighAlarmNote": "40003-40004高报警",
        "HiHiAlarmEnable": "True",
        "HiHiAlarmValue": "100",
        "HiHiAlarmPriority": "0",
        "HiHiAlarmNote": "40003-40004高高报警",
        "ArchivePeriod": "80",
        "SetLimitMax": "100",
        "SetLimitMin": "0",
        "VarType": "Float",
        "StoreType": "HoldingRegister4x",
        "InsertTime": "0",
        "Value": "0",
        "ModbusGroupId": 1
      },
      {
    
        "Id": 5,
        "Number": "5",
        "Name": "Ushort1",
        "Description": "40009",
        "Type": "ModbusTCP",
        "VarAddress": 8,
        "Scale": "1",
        "Offset": "0",
        "Start": "0",
        "AccessProperty": "读写",
        "AlarmEnable": "True",
        "ArchiveEnable": "True",
        "SetLimitEnable": "True",
        "AlarmType": "True",
        "DiscreteAlarmType": "False",
        "DiscreteAlarmPriority": "0",
        "DiscreteAlarmNote": "null",
        "LoLoAlarmEnable": "True",
        "LoLoAlarmValue": "0",
        "LoLoAlarmPriority": "0",
        "LoLoAlarmNote": "40009低低报警",
        "LowAlarmEnable": "True",
        "LowAlarmValue": "20",
        "LowAlarmPriority": "0",
        "LowAlarmNote": "40009低报警",
        "HighAlarmEnable": "True",
        "HighAlarmValue": "80",
        "HighAlarmPriority": "0",
        "HighAlarmNote": "40009高报警",
        "HiHiAlarmEnable": "True",
        "HiHiAlarmValue": "100",
        "HiHiAlarmPriority": "0",
        "HiHiAlarmNote": "40009高高报警",
        "ArchivePeriod": "80",
        "SetLimitMax": "100",
        "SetLimitMin": "0",
        "VarType": "UShort",
        "StoreType": "HoldingRegister4x",
        "InsertTime": "0",
        "Value": "0",
        "ModbusGroupId": 1
      },
      {
    
        "Id": 6,
        "Number": "6",
        "Name": "Ushort2",
        "Description": "40010",
        "Type": "ModbusTCP",
        "VarAddress": 9,
        "Scale": "1",
        "Offset": "0",
        "Start": "0",
        "AccessProperty": "读写",
        "AlarmEnable": "True",
        "ArchiveEnable": "True",
        "SetLimitEnable": "True",
        "AlarmType": "True",
        "DiscreteAlarmType": "False",
        "DiscreteAlarmPriority": "0",
        "DiscreteAlarmNote": "null",
        "LoLoAlarmEnable": "True",
        "LoLoAlarmValue": "0",
        "LoLoAlarmPriority": "0",
        "LoLoAlarmNote": "40009低低报警",
        "LowAlarmEnable": "True",
        "LowAlarmValue": "20",
        "LowAlarmPriority": "0",
        "LowAlarmNote": "40009低报警",
        "HighAlarmEnable": "True",
        "HighAlarmValue": "80",
        "HighAlarmPriority": "0",
        "HighAlarmNote": "40009高报警",
        "HiHiAlarmEnable": "True",
        "HiHiAlarmValue": "100",
        "HiHiAlarmPriority": "0",
        "HiHiAlarmNote": "40009高高报警",
        "ArchivePeriod": "80",
        "SetLimitMax": "100",
        "SetLimitMin": "0",
        "VarType": "UShort",
        "StoreType": "HoldingRegister4x",
        "InsertTime": "0",
        "Value": "0",
        "ModbusGroupId": 1
      }
    ]
  }
}

namespace RedisDemonWebApi
{
    
    public interface IRepository
    {
    
        Book? GetBooksByIdAsync(int a);
    }
}

namespace RedisDemonWebApi
{
    
    public class Repository : IRepository
    {
    
        private MyDbContext db;

        public Repository(MyDbContext db)
        {
    
            this.db = db;
        }


        public Book? GetBooksByIdAsync(int a)
        {
    
            Book? book = db.Books.Where(x => x.Id == a).SingleOrDefault();
            if (book==null)
            {
    
                return null;
            }
            else
            {
    
                return book;
            }
            //return db.Books.Single(x => x.Id == a);
        }
    }
}

依赖注入 :

global using RedisDemonWebApi;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
builder.Services.AddMemoryCache();//内存缓存
builder.Services.AddScoped<IMemoryCacheHelper, MemoryCacheHelper>();
builder.Services.AddDbContext<MyDbContext>();
builder.Services.AddScoped<IRepository, Repository>();
builder.Services.AddStackExchangeRedisCache(opt =>
{
    
    opt.Configuration = "localhost";
    opt.InstanceName = "cache1_";
});

var app = builder.Build();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();

app.UseAuthorization();

app.MapControllers();

app.Run();

控制器:

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Caching.Distributed;
using Microsoft.Extensions.Caching.Memory;
using System.Text.Json;

namespace RedisDemonWebApi.Controllers
{
    
    [Route("api/[controller]/[action]")]
    [ApiController]
    public class TestController : ControllerBase
    {
    
        private readonly IDistributedCache distCache;
        private readonly IDistributedCacheHelper helper;
        private readonly ILogger <TestController> logger;
        private readonly IMemoryCache memCache;
        private readonly IRepository repository;


        public TestController(IRepository repository, IMemoryCache memCache, ILogger<TestController> logger, IDistributedCache distCache)
        {
    
            //this.distCache = distCache;
            //this.helper = helper;
            this.repository = repository;
            this.memCache = memCache;
            this.logger = logger;
            this.distCache = distCache;
        }

        //[HttpGet]
        //public string Now()
        //{
    
        // string s = distCache.GetString("Now");
        // if (s == null)
        // {
    
        // s = DateTime.Now.ToString();
        // var opt = new DistributedCacheEntryOptions();
        // opt.AbsoluteExpirationRelativeToNow = TimeSpan.FromSeconds(30);
        // distCache.SetString("Now", s, opt);
        // }
        // return s;
        //}

        [HttpGet]
        //public ActionResult<Book?> GetBookById(int Id)
        //{
    
        // Book? book = repository.GetBooksByIdAsync(Id);
        // return Ok(book);
        //}

        //内存缓存
        public async Task<ActionResult<Book?>> GetBookById(int Id)
        {
    
            logger.LogInformation($"开始执行GetBookById,Id={
      Id}");
            //先查找内存缓存, 没有再进入repository查找
            Book? b = await memCache.GetOrCreateAsync("Book" + Id, async (e) =>
               {
    
                   logger.LogInformation($"缓存中没找到,去数据库,Id={
      Id}");
                   return repository.GetBooksByIdAsync(Id);
               });
            logger.LogInformation($"GetOrCreateAsync结果{
      b}");
            if (b == null)
            {
    
                return NotFound("找不到");
            }
            else
            {
    
                return Ok(b);
            }
        }

        //分布式缓存
        [HttpGet]
        public async Task<ActionResult<Book?>> GetBookFromRedisById(int Id)
        {
    
            Book? book=null;
            logger.LogInformation($"开始执行GetBookById,Id={
      Id}");
            //先去分布式缓存中寻找
            string? s = await distCache.GetStringAsync("Book" + Id);
            //如果没找到, 去数据库中去找, 然后存入分布式缓存
            if (s==null)
            {
    
                logger.LogInformation($"缓存中没找到,去数据库找,Id={
      Id}");
                book = repository.GetBooksByIdAsync(Id);

                //设置Redis中的过期时间opt
                var opt = new DistributedCacheEntryOptions();
                opt.AbsoluteExpirationRelativeToNow = TimeSpan.FromSeconds(30);
                //json序列化成字符串存入缓存中
                await distCache.SetStringAsync("Book" + Id, JsonSerializer.Serialize(book), opt);
                logger.LogInformation($"在数据库中找到,Id={
      Id},将其序列化为字符串存入Redis");
            }

            //如果在缓存中找到, 需要将缓存中的字符串s反序列化为book
            else
            {
    
                book = JsonSerializer.Deserialize<Book?>(s);
                logger.LogInformation($"直接在Redis中找到了,Id={
      Id}");
            }

            //都没找到就是不存在了
            if (book==null)
            {
    
                logger.LogInformation($"数据库和Redis中都不存在Id={
      Id}的书籍");
                return NotFound("不存在");
            }
            else
            {
    
                return book;
            }
        }



    }
}

使用Swagger 测试 :

日志 :

info: Microsoft.Hosting.Lifetime[14]
      Now listening on: https://localhost:7063
info: Microsoft.Hosting.Lifetime[14]
      Now listening on: http://localhost:5063
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
      Content root path: D:\cSharpe\code\RedisDemon1\RedisDemonWebApi\
info: RedisDemonWebApi.Controllers.TestController[0]
      开始执行GetBookById,Id=2
info: RedisDemonWebApi.Controllers.TestController[0]
      缓存中没找到,去数据库找,Id=2
info: RedisDemonWebApi.Controllers.TestController[0]
      在数据库中找到,Id=2,将其序列化为字符串存入Redis
info: RedisDemonWebApi.Controllers.TestController[0]
      开始执行GetBookById,Id=2
info: RedisDemonWebApi.Controllers.TestController[0]
      直接在Redis中找到了,Id=2

Redis中 :

如果查询的Id对应的内容不存在, 则Redis也会把null值存在Redis, 这样避免了缓存穿透的问题