Exception when generating Postman collection for request bodies containing a property of type IList<string>

[Aleksandr-Khvalov]

When generating postman collection, an exception occurs if a controller request body contains a property of type IList<string>. The issue arises because the code attempts to instantiate string elements using Activator.CreateInstance, which is not supported for the string type.

Error Message

Unhandled exception. System.MissingMethodException: Cannot dynamically create an instance of type 'System.String'. Reason: Uninitialized Strings cannot be created.
   at System.RuntimeType.ActivatorCache..ctor(RuntimeType rt)
   at System.RuntimeType.IGenericCacheEntry`1.CreateAndCache(RuntimeType type)
   at System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean wrapExceptions)
   at Simplify.Web.Postman.Assembly.Collection.PartBuilders.RequestBuilder.InitializeListsSingleEmptyValues(Object model)
   at Simplify.Web.Postman.Assembly.Collection.PartBuilders.RequestBuilder.BuildRequestJsonData(Type modelType)
   at Simplify.Web.Postman.Assembly.Collection.PartBuilders.RequestBuilder.TryBuildBody(IControllerMetadata metaData)
   at Simplify.Web.Postman.Assembly.Collection.PartBuilders.RequestBuilder.Build(IControllerMetadata metaData, KeyValuePair`2 route)
   at Simplify.Web.Postman.Assembly.Collection.PartBuilders.CollectionItemsBuilder.BuildRequestCollectionItem(IControllerMetadata metaData, KeyValuePair`2 route)
   at Simplify.Web.Postman.Assembly.Collection.PartBuilders.CollectionItemsBuilder.Build(CollectionModel model)
   at Simplify.Web.Postman.Assembly.Collection.CollectionBuilder.Create()
   at Simplify.Web.Postman.Generators.FileBasedCollectionGenerator.Generate()
   at Simplify.Web.Postman.Generators.FileBasedPostmanGenerator.Generate()
   at Simplify.Web.Postman.Setup.SimplifyDIContextHandlerExtensions.GeneratePostmanData(IDIContextHandler contextHandler)

Steps to Reproduce

1. Create a controller with a request model containing a IList<string> property.
2. Attempt to generate a Postman collection.
3. Observe the MissingMethodException during collection generation.

Expected Behavior

The package should handle IList<string> and string properties gracefully, initializing string elements as empty strings or with a suitable default value, so that Postman collections can be generated for all valid request models without exceptions.

Solution

The fix involves:

• Checking for string types before attempting to use Activator.CreateInstance.
• Returning string.Empty for string types instead of using the activator.