restores the MB enable flag

src/Umbraco.ModelsBuilder.Embedded/Configuration/ModelsBuilderConfig.cs

@@ -22,11 +22,18 @@ namespace Umbraco.ModelsBuilder.Embedded.Configuration
         {
             const string prefix = "Umbraco.ModelsBuilder.";
 
+            // giant kill switch, default: false
+            // must be explicitely set to true for anything else to happen
+            Enable = ConfigurationManager.AppSettings[prefix + "Enable"] == "true";
+
             // ensure defaults are initialized for tests
             ModelsNamespace = DefaultModelsNamespace;
             ModelsDirectory = IOHelper.MapPath(DefaultModelsDirectory);
             DebugLevel = 0;
 
+            // stop here, everything is false
+            if (!Enable) return;
+
             // mode
             var modelsMode = ConfigurationManager.AppSettings[prefix + "ModelsMode"];
             if (!string.IsNullOrWhiteSpace(modelsMode))
@@ -94,6 +101,7 @@ namespace Umbraco.ModelsBuilder.Embedded.Configuration
         /// Initializes a new instance of the <see cref="ModelsBuilderConfig"/> class.
         /// </summary>
         public ModelsBuilderConfig(
+            bool enable = false,
             ModelsMode modelsMode = ModelsMode.Nothing,
             string modelsNamespace = null,
             bool enableFactory = true,
@@ -102,6 +110,7 @@ namespace Umbraco.ModelsBuilder.Embedded.Configuration
             bool acceptUnsafeModelsDirectory = false,
             int debugLevel = 0)
         {
+            Enable = enable;
             ModelsMode = modelsMode;
 
             ModelsNamespace = string.IsNullOrWhiteSpace(modelsNamespace) ? DefaultModelsNamespace : modelsNamespace;
@@ -143,6 +152,15 @@ namespace Umbraco.ModelsBuilder.Embedded.Configuration
             throw new ConfigurationErrorsException($"Invalid models directory \"{config}\".");
         }
 
+        /// <summary>
+        /// Gets a value indicating whether the whole models experience is enabled.
+        /// </summary>
+        /// <remarks>
+        ///     <para>If this is false then absolutely nothing happens.</para>
+        ///     <para>Default value is <c>false</c> which means that unless we have this setting, nothing happens.</para>
+        /// </remarks>
+        public bool Enable { get; }
+
         /// <summary>
         /// Gets the models mode.
         /// </summary>