Database 配置源

数据库配置源支持从关系型数据库读取和写入配置，适合需要集中管理配置的场景。

安装

dotnet add package Apq.Cfg.Database

默认层级

该配置源的默认层级为 CfgSourceLevels.Database (100)。

如果不指定 level 参数，将使用默认层级：

// 使用默认层级 100
.AddDatabase(options => { ... })

// 指定自定义层级
.AddDatabase(options => { ... }, level: 150)

支持的数据库

数据库	Provider 值
Microsoft SQL Server	SqlServer
MySQL	MySql
PostgreSQL	PostgreSQL 或 Postgres
Oracle	Oracle
SQLite	SQLite

基本用法

using Apq.Cfg;
using Apq.Cfg.Database;

var cfg = new CfgBuilder()
    .AddDatabase(options =>
    {
        options.Provider = "SqlServer";
        options.ConnectionString = "Server=localhost;Database=ConfigDb;Trusted_Connection=True;";
        options.Table = "AppConfig";
        options.KeyColumn = "ConfigKey";
        options.ValueColumn = "ConfigValue";
    })  // 使用默认层级 100
    .Build();

// 读取配置
var connStr = cfg["Database:ConnectionString"];
var timeout = cfg.GetValue<int>("Database:Timeout");

方法签名

public static CfgBuilder AddDatabase(
    this CfgBuilder builder,
    Action<DatabaseOptions> configure,
    int level,
    bool isPrimaryWriter = false)

配置选项

完整配置

var cfg = new CfgBuilder()
    .AddDatabase(options =>
    {
        options.Provider = "SqlServer";
        options.ConnectionString = "Server=localhost;Database=ConfigDb;...";
        options.Table = "AppConfig";
        options.KeyColumn = "ConfigKey";
        options.ValueColumn = "ConfigValue";
        options.CommandTimeoutMs = 5000;
    }, isPrimaryWriter: true)  // 使用默认层级 100
    .Build();

选项说明

选项	类型	默认值	说明
Provider	string?	null	数据库提供程序名称
ConnectionString	string?	null	数据库连接字符串
Table	string?	null	配置表名
KeyColumn	string?	null	键列名
ValueColumn	string?	null	值列名
CommandTimeoutMs	int	5000	命令超时时间（毫秒）

数据表结构

SQL Server

CREATE TABLE AppConfig (
    ConfigKey NVARCHAR(256) PRIMARY KEY,
    ConfigValue NVARCHAR(MAX)
);

MySQL

CREATE TABLE app_config (
    config_key VARCHAR(256) PRIMARY KEY,
    config_value TEXT
);

PostgreSQL

CREATE TABLE app_config (
    config_key VARCHAR(256) PRIMARY KEY,
    config_value TEXT
);

SQLite

CREATE TABLE Config (
    Key TEXT PRIMARY KEY,
    Value TEXT
);

各数据库示例

SQL Server

var cfg = new CfgBuilder()
    .AddDatabase(options =>
    {
        options.Provider = "SqlServer";
        options.ConnectionString = "Server=.;Database=MyDb;Trusted_Connection=True;";
        options.Table = "AppConfig";
        options.KeyColumn = "Key";
        options.ValueColumn = "Value";
    })  // 使用默认层级 100
    .Build();

MySQL

var cfg = new CfgBuilder()
    .AddDatabase(options =>
    {
        options.Provider = "MySql";
        options.ConnectionString = "Server=localhost;Database=mydb;User=root;Password=...;";
        options.Table = "app_config";
        options.KeyColumn = "config_key";
        options.ValueColumn = "config_value";
    })  // 使用默认层级 100
    .Build();

PostgreSQL

var cfg = new CfgBuilder()
    .AddDatabase(options =>
    {
        options.Provider = "PostgreSQL";
        options.ConnectionString = "Host=localhost;Database=mydb;Username=postgres;Password=...;";
        options.Table = "app_config";
        options.KeyColumn = "config_key";
        options.ValueColumn = "config_value";
    })  // 使用默认层级 100
    .Build();

Oracle

var cfg = new CfgBuilder()
    .AddDatabase(options =>
    {
        options.Provider = "Oracle";
        options.ConnectionString = "Data Source=localhost:1521/ORCL;User Id=user;Password=...;";
        options.Table = "APP_CONFIG";
        options.KeyColumn = "CONFIG_KEY";
        options.ValueColumn = "CONFIG_VALUE";
    })  // 使用默认层级 100
    .Build();

SQLite

var cfg = new CfgBuilder()
    .AddDatabase(options =>
    {
        options.Provider = "SQLite";
        options.ConnectionString = "Data Source=config.db";
        options.Table = "Config";
        options.KeyColumn = "Key";
        options.ValueColumn = "Value";
    })  // 使用默认层级 100
    .Build();

可写配置

数据库配置源支持写入配置：

var cfg = new CfgBuilder()
    .AddDatabase(options =>
    {
        options.Provider = "SqlServer";
        options.ConnectionString = "Server=localhost;Database=ConfigDb;...";
        options.Table = "AppConfig";
        options.KeyColumn = "ConfigKey";
        options.ValueColumn = "ConfigValue";
    }, isPrimaryWriter: true)  // 使用默认层级 100
    .Build();

// 写入配置
cfg["App:Version"] = "2.0.0";
await cfg.SaveAsync();

与本地配置混合使用

var cfg = new CfgBuilder()
    // 本地基础配置
    .AddJsonFile("config.json")
    // 数据库配置（使用默认层级 100）
    .AddDatabase(options =>
    {
        options.Provider = "SqlServer";
        options.ConnectionString = "Server=localhost;Database=ConfigDb;...";
        options.Table = "AppConfig";
        options.KeyColumn = "ConfigKey";
        options.ValueColumn = "ConfigValue";
    }, isPrimaryWriter: true)
    // 环境变量（使用默认层级 400）
    .AddEnvironmentVariables(prefix: "APP_")
    .Build();

初始化数据

可以使用 SQL 脚本初始化配置数据：

-- SQL Server
INSERT INTO AppConfig (ConfigKey, ConfigValue) VALUES
('Database:Host', 'localhost'),
('Database:Port', '5432'),
('Database:Name', 'mydb'),
('App:Name', 'MyApplication'),
('App:Version', '1.0.0');

下一步

• Redis 配置源 - Redis 键值存储
• Consul 配置源 - HashiCorp Consul