02_Web Api使用Jwt

JWT（JSON Web Token）是一種用於在網絡應用之間傳遞信息的開放標準（RFC 7519）。它使用 JSON 對象在安全可靠的方式下傳遞信息，通常用於身份驗證和信息交換。

在Web API中，JWT通常用於對用戶進行身份驗證和授權。當用戶登錄成功後，服務器會生成一個Token並返回給客戶端，客戶端在接下來的請求中攜帶該Token來進行身份驗證。

使用：

安裝包：JWT

1.添加一個Web Api項目

appsettings.json設置

"JWT": { 
    "SecretKey": "123456789ffffffffffffffffffffffffffffffffffff", //私鑰
    "Issuer": "zhansan", //發佈者
    "Audience": "lisi" //接收者
  }

 

2.添加一個控制器用於獲取Token

    [Route("api/[controller]/[action]")]
    [ApiController]
    public class TokenController : ControllerBase
    {
        public readonly IConfiguration configuration;
        public TokenController(IConfiguration configuration)
        {
            this.configuration = configuration;
        }

        [HttpGet]
        public string GetToken()
        {//HmacSha256算法
            var signingAlogorithm = SecurityAlgorithms.HmacSha256;
            //存放用戶信息 
            var claims = new[]
            {
                new Claim(JwtRegisteredClaimNames.Sub,"userId"),
                new Claim(ClaimTypes.Role,"admin"),
                new Claim(ClaimTypes.Name,"ClaimTypesName"),new Claim("policy","EmployeeNumber"),
            };//取出私鑰並以utf8編碼字節輸出
            var secretByte = Encoding.UTF8.GetBytes(configuration["JWT:SecretKey"]);
            //使用非對稱算法對私鑰進行加密
            var signingKey = new SymmetricSecurityKey(secretByte);
            //使用HmacSha256來驗證加密後的私鑰生成數字簽名
            var signingCredentials = new SigningCredentials(signingKey, signingAlogorithm);
            //生成Token
            var Token = new JwtSecurityToken(
                    issuer: configuration["JWT:Issuer"],        //發佈者
                    audience: configuration["JWT:Audience"],    //接收者
                    claims: claims,                             //存放的用戶信息
                    notBefore: DateTime.UtcNow,                 //發佈時間
                    expires: DateTime.UtcNow.AddDays(1),        //有效期設置爲1天
                    signingCredentials                           //數字簽名
                );
            //生成字符串token
            var _Tokenstring = new JwtSecurityTokenHandler().WriteToken(Token);

            return _Tokenstring;
        }
    }

 

3.Program.cs設置

public class Program
    {
        public static void Main(string[] args)
        {
            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(c =>
            {
                //版本控制
                foreach (FieldInfo field in typeof(EditionV).GetFields())
                {
                    c.SwaggerDoc(field.Name, new OpenApiInfo()
                    {
                        Title = field.Name + "版本",
                        Version = field.Name,
                        Description = $"{field.Name}版本"
                    });
                }
                //爲swagger UI設置xml文檔註釋路徑
                var file = Path.Combine(AppContext.BaseDirectory, "WebApiApp.xml");  // xml文檔絕對路徑
                var path = Path.Combine(AppContext.BaseDirectory, file); // xml文檔絕對路徑
                c.IncludeXmlComments(path, true); // true : 顯示控制器層註釋
                c.OrderActionsBy(o => o.RelativePath); // 對action的名稱進行排序，如果有多個，就可以看見效果了。

                //註冊到swagger中
                c.AddSecurityDefinition("Bearer", new OpenApiSecurityScheme
                {
                    Description = "Value: Bearer {token}",
                    Name = "Authorization",
                    In = ParameterLocation.Header,
                    Type = SecuritySchemeType.ApiKey,
                    Scheme = "Bearer"
                });

                c.AddSecurityRequirement(new OpenApiSecurityRequirement()
                {{
                    new OpenApiSecurityScheme
                    {
                        Reference = new OpenApiReference
                        {
                            Type = ReferenceType.SecurityScheme,
                            Id = "Bearer"
                        }, Scheme = "oauth2", Name = "Bearer", In = ParameterLocation.Header }, new List<string>()
                    }
                });
            });

            //策略授權
            builder.Services.AddAuthorization(options =>
            {
                options.AddPolicy("policy", policy => policy.RequireClaim("policy"));
            });

            //身份認證--如何鑑權 
            builder.Services.AddAuthentication(options =>
            {
                //options.DefaultScheme = JwtBearerDefaults.AuthenticationScheme;
                options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
                options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
            })
            .AddJwtBearer(options =>
            {
                //取出私鑰
                var secretByte = Encoding.UTF8.GetBytes(builder.Configuration["JWT:SecretKey"]);
                options.TokenValidationParameters = new TokenValidationParameters()
                {
                    //驗證發佈者
                    ValidateIssuer = true,
                    ValidIssuer = builder.Configuration["JWT:Issuer"],
                    //驗證接收者
                    ValidateAudience = true,
                    ValidAudience = builder.Configuration["JWT:Audience"],
                    //ValidateIssuerSigningKey= true,//是否驗證SigningKey
                    //驗證是否過期
                    ValidateLifetime = true,
                    //驗證私鑰
                    IssuerSigningKey = new SymmetricSecurityKey(secretByte)
                };
            });

            //配置跨域服務
            builder.Services.AddCors(options =>
            {
                options.AddPolicy("cross", p =>
                {
                    p.AllowAnyOrigin()
                    .AllowAnyMethod()
                    .AllowAnyHeader();
                });
            });

            var app = builder.Build();

            // Configure the HTTP request pipeline.
            if (app.Environment.IsDevelopment())
            {
                app.UseSwagger();
                app.UseSwaggerUI(c =>
                {
                    foreach (FieldInfo field in typeof(EditionV).GetFields())
                    {
                        c.SwaggerEndpoint($"/swagger/{field.Name}/swagger.json", $"{field.Name}");
                    }
                });
            }
            app.UseCors("cross");  //跨域
            app.UseHttpsRedirection();

            app.UseAuthentication(); //鑑權
            app.UseAuthorization();//授權

            app.MapControllers();
            app.Run();
        }
    }

 

4.swagger設置

    /// <summary>
    /// 版本
    /// </summary>
    public static class EditionV
    {
        public static string V1;
        public static string V2;
        public static string V3;
        public static string V4;
        public static string V5;
    }

添加一個WebApiApp.xml文件，屬性：複製到輸出目錄：始終複製

項目--->屬性--->文檔文件勾上。

 

5.添加一個UserInfoController.cs用於測試

    [Route("api/[controller]/[action]")]
    [ApiController]
    [ApiExplorerSettings(GroupName =nameof(EditionV.V1))]
    public class UserInfoController : ControllerBase
    {
        /// <summary>
        /// 獲取用戶
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        [HttpGet]
        [Authorize]
        public string GetUser(string id)
        {
            return $"用戶id{id}---姓名：張三";
        }

        /// <summary>
        /// 獲取用戶名
        /// </summary>
        /// <returns></returns>
        [Authorize(Roles = "admin")]
        [HttpPost]
        public string GetUserName()
        {
            return "你好，我是李四";
        }
/// <summary>
        /// 獲取用戶顏色
        /// </summary>
        /// <returns></returns>
        [Authorize(Policy = "policy")]
        [HttpPost]
        public string GetUserColour()
        {
            return "我衣服的顏色爲紅色";
        }
    }