修改 CloudProduct ImageCache 项目改为 插件

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();
+    }
+}