edit

XLAB2/Infrastructure/DatabaseConfiguration.cs

@@ -0,0 +1,73 @@
+using Microsoft.Extensions.Configuration;
+using System;
+using System.Threading;
+
+namespace XLAB2.Infrastructure;
+
+internal static class DatabaseConfiguration
+{
+    private static readonly Lazy<DatabaseOptions> Options = new(LoadOptions, LazyThreadSafetyMode.ExecutionAndPublication);
+
+    public static DatabaseOptions Current => Options.Value;
+
+    private static DatabaseOptions LoadOptions()
+    {
+        var configuration = new ConfigurationBuilder()
+            .SetBasePath(AppContext.BaseDirectory)
+            .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
+            .AddEnvironmentVariables(prefix: "XLAB2_")
+            .Build();
+
+        var options = configuration.GetSection("Database").Get<DatabaseOptions>() ?? new DatabaseOptions();
+        Validate(options);
+        return options;
+    }
+
+    private static void Validate(DatabaseOptions options)
+    {
+        if (string.IsNullOrWhiteSpace(options.Server))
+        {
+            throw new InvalidOperationException("Database:Server is required.");
+        }
+
+        if (string.IsNullOrWhiteSpace(options.Database))
+        {
+            throw new InvalidOperationException("Database:Database is required.");
+        }
+
+        if (options.ConnectTimeoutSeconds <= 0)
+        {
+            throw new InvalidOperationException("Database:ConnectTimeoutSeconds must be greater than zero.");
+        }
+
+        if (options.CommandTimeoutSeconds <= 0)
+        {
+            throw new InvalidOperationException("Database:CommandTimeoutSeconds must be greater than zero.");
+        }
+
+        if (options.MinPoolSize < 0)
+        {
+            throw new InvalidOperationException("Database:MinPoolSize cannot be negative.");
+        }
+
+        if (options.MaxPoolSize <= 0)
+        {
+            throw new InvalidOperationException("Database:MaxPoolSize must be greater than zero.");
+        }
+
+        if (options.MinPoolSize > options.MaxPoolSize)
+        {
+            throw new InvalidOperationException("Database:MinPoolSize cannot be greater than Database:MaxPoolSize.");
+        }
+
+        if (options.ConnectRetryCount < 0)
+        {
+            throw new InvalidOperationException("Database:ConnectRetryCount cannot be negative.");
+        }
+
+        if (options.ConnectRetryIntervalSeconds < 1)
+        {
+            throw new InvalidOperationException("Database:ConnectRetryIntervalSeconds must be greater than zero.");
+        }
+    }
+}