add StorageSettingsExtensions

Related to: aliencube#319

src/AzureOpenAIProxy.ApiApp/Extensions/StorageSettingsExtensions.cs

@@ -0,0 +1,26 @@
+using AzureOpenAIProxy.ApiApp.Configurations;
+
+
+namespace AzureOpenAIProxy.ApiApp.Extensions;
+
+/// <summary>
+/// This represents the extension entity for the <see cref="StorageSettings"/> class.
+/// </summary>
+public static class StorageSettingsExtensions
+{  
+    /// <summary>
+    /// Gets the Storage configuration settings by reading appsettings.json.
+    /// </summary>
+    /// <param name="services"><see cref="IServiceCollection"/> instance.</param>
+    /// <returns>Returns <see cref="StorageSettings"/> instance.</returns>
+    public static StorageSettings GetStorageSettings(this IServiceCollection services)
+    {
+        var configuration = services.BuildServiceProvider().GetService<IConfiguration>()
+            ?? throw new InvalidOperationException($"{nameof(IConfiguration)} service is not registered.");
+
+        var settings = configuration.GetSection(StorageSettings.Name).Get<StorageSettings>()
+            ?? throw new InvalidOperationException($"{nameof(StorageSettings)} could not be retrieved from the configuration.");
+
+        return settings;
+    }
+}