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JSON 配置源

JSON 是最常用的配置格式,Apq.Cfg 核心包内置支持。

安装

JSON 配置源包含在核心包中,无需额外安装:

bash
dotnet add package Apq.Cfg

基本用法

加载 JSON 文件

csharp
var cfg = new CfgBuilder()
    .AddJson("config.json", level: 0, writeable: false)
    .Build();

可选文件

csharp
var cfg = new CfgBuilder()
    .AddJson("config.json", level: 0, writeable: false)
    .AddJson("config.local.json", level: 1, writeable: false, optional: true)
    .Build();

启用重载

csharp
var cfg = new CfgBuilder()
    .AddJson("config.json", level: 0, writeable: false, reloadOnChange: true)
    .Build();

可写配置

csharp
var cfg = new CfgBuilder()
    .AddJson("config.json", level: 0, writeable: true, isPrimaryWriter: true)
    .Build();

// 修改配置
cfg.Set("App:Name", "NewName");
await cfg.SaveAsync();

JSON 文件格式

基本结构

json
{
  "App": {
    "Name": "MyApplication",
    "Version": "1.0.0"
  },
  "Database": {
    "Host": "localhost",
    "Port": 5432,
    "Database": "mydb",
    "Username": "admin",
    "Password": "secret"
  },
  "Logging": {
    "Level": "Information",
    "EnableConsole": true
  }
}

数组配置

json
{
  "Servers": [
    "server1.example.com",
    "server2.example.com",
    "server3.example.com"
  ],
  "Endpoints": [
    {
      "Name": "api",
      "Url": "https://api.example.com",
      "Timeout": 30
    },
    {
      "Name": "auth",
      "Url": "https://auth.example.com",
      "Timeout": 10
    }
  ]
}

读取数组

csharp
// 按索引访问
var firstServer = cfg.Get("Servers:0");
var firstEndpointName = cfg.Get("Endpoints:0:Name");

// 获取配置节
var serversSection = cfg.GetSection("Servers");
var endpointsSection = cfg.GetSection("Endpoints");

键路径映射

JSON 结构会被扁平化为冒号分隔的键路径:

JSON 路径配置键
App.NameApp:Name
Database.HostDatabase:Host
Servers[0]Servers:0
Endpoints[0].NameEndpoints:0:Name

高级选项

指定编码

csharp
var options = new EncodingOptions
{
    ReadStrategy = EncodingReadStrategy.Specified,
    ReadEncoding = Encoding.UTF8
};

var cfg = new CfgBuilder()
    .AddJson("config.json", level: 0, writeable: false, encoding: options)
    .Build();

从流加载

csharp
using var stream = File.OpenRead("config.json");
var cfg = new CfgBuilder()
    .AddSource(new JsonStreamCfgSource(stream, level: 0))
    .Build();

环境特定配置

典型模式

csharp
var environment = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT") ?? "Production";

var cfg = new CfgBuilder()
    .AddJson("config.json", level: 0, writeable: false)
    .AddJson($"config.{environment}.json", level: 1, writeable: false, optional: true)
    .AddEnvironmentVariables(level: 2, prefix: "APP_")
    .Build();

配置文件示例

config.json (基础配置):

json
{
  "Logging": {
    "Level": "Warning"
  },
  "Database": {
    "Host": "localhost",
    "Port": 5432
  }
}

config.Development.json (开发环境):

json
{
  "Logging": {
    "Level": "Debug"
  }
}

config.Production.json (生产环境):

json
{
  "Database": {
    "Host": "prod-db.example.com"
  }
}

下一步

基于 MIT 许可发布