修改 CloudProduct ImageCache 项目改为 插件

Core/MAX.Plugins/IPlugin.cs

@@ -0,0 +1,13 @@
+using Microsoft.AspNetCore.Builder;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace MAX.Plugins;
+
+/// <summary>独立插件入口。实现类必须具有无参构造函数。</summary>
+public interface IPlugin
+{
+    string Id { get; }
+    int Priority { get; }
+    void ConfigureServices(IServiceCollection services, PluginContext context);
+    void Configure(IApplicationBuilder app, PluginContext context);
+}

Core/MAX.Plugins/MAX.Plugins.csproj

@@ -0,0 +1,3 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <ItemGroup><FrameworkReference Include="Microsoft.AspNetCore.App" /></ItemGroup>
+</Project>

Core/MAX.Plugins/PluginBase.cs

@@ -0,0 +1,32 @@
+using Microsoft.AspNetCore.Builder;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace MAX.Plugins;
+
+public abstract class PluginBase : IPlugin
+{
+    public abstract string Id { get; }
+    public virtual int Priority => 0;
+    protected PluginContext Context { get; private set; } = null!;
+
+    public void ConfigureServices(IServiceCollection services, PluginContext context)
+    {
+        ArgumentNullException.ThrowIfNull(services);
+        ArgumentNullException.ThrowIfNull(context);
+        if (!string.Equals(Id, context.Id, StringComparison.Ordinal))
+            throw new ArgumentException("插件上下文标识不匹配。", nameof(context));
+        if (Context is not null) throw new InvalidOperationException($"插件 {Id} 已注册。");
+        Context = context;
+        RegisterServices(services);
+    }
+
+    public void Configure(IApplicationBuilder app, PluginContext context)
+    {
+        if (!ReferenceEquals(Context, context))
+            throw new InvalidOperationException($"插件 {Id} 尚未注册或上下文不匹配。");
+        ConfigureApplication(app);
+    }
+    protected abstract void RegisterServices(IServiceCollection services);
+    protected virtual void ConfigureApplication(IApplicationBuilder app) { }
+    protected string RequireConfiguration(string key) => Context.RequireConfiguration(key);
+}

Core/MAX.Plugins/PluginContext.cs

@@ -0,0 +1,39 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.Hosting;
+
+namespace MAX.Plugins;
+
+/// <summary>插件独立配置，不合并宿主或其他插件配置。</summary>
+public sealed class PluginContext : IDisposable
+{
+    private int disposed;
+    public string Id { get; }
+    public string DirectoryPath { get; }
+    public IHostEnvironment Environment { get; }
+    public IConfigurationRoot Configuration { get; }
+
+    public PluginContext(string id, string directoryPath, IHostEnvironment environment)
+    {
+        ArgumentException.ThrowIfNullOrWhiteSpace(id);
+        ArgumentNullException.ThrowIfNull(environment);
+        Id = id;
+        DirectoryPath = Path.GetFullPath(directoryPath);
+        Environment = environment;
+        Configuration = new ConfigurationBuilder()
+            .SetBasePath(DirectoryPath)
+            .AddJsonFile("appsettings.json", optional: false, reloadOnChange: false)
+            .AddJsonFile($"appsettings.{environment.EnvironmentName}.json", optional: true, reloadOnChange: false)
+            .AddEnvironmentVariables($"Plugins__{id}__")
+            .Build();
+    }
+
+    public string RequireConfiguration(string key) =>
+        !string.IsNullOrWhiteSpace(Configuration[key]) ? Configuration[key]!
+            : throw new InvalidOperationException($"插件 {Id} 缺少配置 {key}，请检查 {Path.Combine(DirectoryPath, "appsettings.json")}。");
+
+    public void Dispose()
+    {
+        if (Interlocked.Exchange(ref disposed, 1) == 0)
+            (Configuration as IDisposable)?.Dispose();
+    }
+}