ContentAtXPath > JsonReaderException: Unexpected character encountered while parsing value

[deekoulos]

Which Umbraco version are you using? (Please write the exact version, example: 10.1.0)

10.2.0

Bug summary

Umbraco.ContentAtXPath("//home").ToList(); throws the following exception - (Using nested content and dropdowns in element types):

An unhandled exception occurred while processing the request.
JsonReaderException: Unexpected character encountered while parsing value: F. Path '', line 0, position 0.
Newtonsoft.Json.JsonTextReader.ParseValue()
Newtonsoft.Json.JsonReader.ReadForType(JsonContract contract, bool hasConverter)
Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, bool checkAdditionalContent)
Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)
Newtonsoft.Json.JsonConvert.DeserializeObject(string value, Type type, JsonSerializerSettings settings)
Umbraco.Cms.Core.PropertyEditors.ValueConverters.FlexibleDropdownPropertyValueConverter.ConvertSourceToIntermediate(IPublishedElement owner, IPublishedPropertyType propertyType, object source, bool preview)
Umbraco.Cms.Core.Models.PublishedContent.PublishedPropertyType.ConvertSourceToInter(IPublishedElement owner, object source, bool preview)
Umbraco.Cms.Infrastructure.PublishedCache.Property.GetInterValue(string culture, string segment)
Umbraco.Cms.Infrastructure.PublishedCache.Property.GetXPathValue(string culture, string segment)
Umbraco.Cms.Core.Xml.XPath.NavigableNavigator.MoveToFirstChildProperty()
Umbraco.Cms.Core.Xml.XPath.NavigableNavigator.MoveToFirstChild()
MS.Internal.Xml.XPath.XPathDescendantIterator.MoveNext()
MS.Internal.Xml.XPath.DescendantQuery.Advance()
MS.Internal.Xml.XPath.XPathSelectionIterator.MoveNext()
Umbraco.Cms.Infrastructure.PublishedCache.ContentCache.GetByXPath(XPathNodeIterator iterator)+MoveNext()
System.Collections.Generic.List<T>..ctor(IEnumerable<T> collection)
System.Linq.Enumerable.ToList<TSource>(IEnumerable<TSource> source)
AspNetCore.Views_Partials_Widgets__heroWithSearch.ExecuteAsync() in _heroWithSearch.cshtml
+
    var test = Umbraco.ContentAtXPath("//home").ToList();
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageCoreAsync(IRazorPage page, ViewContext context)
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageAsync(IRazorPage page, ViewContext context, bool invokeViewStarts)
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderAsync(ViewContext context)
Microsoft.AspNetCore.Mvc.ViewFeatures.HtmlHelper.RenderPartialCoreAsync(string partialViewName, object model, ViewDataDictionary viewData, TextWriter writer)
Microsoft.AspNetCore.Mvc.ViewFeatures.HtmlHelper.PartialAsync(string partialViewName, object model, ViewDataDictionary viewData)
AspNetCore.Views_Partials_Widgets__RenderWidgets.<ExecuteAsync>g__RenderWidget|0_0(IPublishedElement widget, int order) in _RenderWidgets.cshtml
+
        @(await Html.PartialAsync(partialView, widget))
AspNetCore.Views_Partials_Widgets__RenderWidgets.ExecuteAsync() in _RenderWidgets.cshtml
+
        await RenderWidget(widget, index);
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageCoreAsync(IRazorPage page, ViewContext context)
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageAsync(IRazorPage page, ViewContext context, bool invokeViewStarts)
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderAsync(ViewContext context)
Microsoft.AspNetCore.Mvc.ViewFeatures.HtmlHelper.RenderPartialCoreAsync(string partialViewName, object model, ViewDataDictionary viewData, TextWriter writer)
Microsoft.AspNetCore.Mvc.ViewFeatures.HtmlHelper.PartialAsync(string partialViewName, object model, ViewDataDictionary viewData)
AspNetCore.Views_Page.ExecuteAsync() in Page.cshtml
+
@await Html.PartialAsync("~/Views/Partials/Widgets/_RenderWidgets.cshtml")
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageCoreAsync(IRazorPage page, ViewContext context)
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderPageAsync(IRazorPage page, ViewContext context, bool invokeViewStarts)
Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderAsync(ViewContext context)
Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor.ExecuteAsync(ViewContext viewContext, string contentType, Nullable<int> statusCode)
Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor.ExecuteAsync(ViewContext viewContext, string contentType, Nullable<int> statusCode)
Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor.ExecuteAsync(ActionContext actionContext, IView view, ViewDataDictionary viewData, ITempDataDictionary tempData, string contentType, Nullable<int> statusCode)
Microsoft.AspNetCore.Mvc.ViewFeatures.ViewResultExecutor.ExecuteAsync(ActionContext context, ViewResult result)
Microsoft.AspNetCore.Mvc.ViewResult.ExecuteResultAsync(ActionContext context)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResultFilterAsync>g__Awaited|30_0<TFilter, TFilterAsync>(ResourceInvoker invoker, Task lastTask, State next, Scope scope, object state, bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResultExecutedContextSealed context)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.ResultNext<TFilter, TFilterAsync>(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeResultFilters()
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|25_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, object state, bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
Umbraco.Cms.Web.Common.Middleware.BasicAuthenticationMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
Microsoft.AspNetCore.Builder.UseMiddlewareExtensions+<>c__DisplayClass6_1+<<UseMiddlewareInterface>b__1>d.MoveNext()
Umbraco.Cms.Web.BackOffice.Middleware.BackOfficeExternalLoginProviderErrorMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
Microsoft.AspNetCore.Builder.UseMiddlewareExtensions+<>c__DisplayClass6_1+<<UseMiddlewareInterface>b__1>d.MoveNext()
Microsoft.AspNetCore.Session.SessionMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Session.SessionMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Localization.RequestLocalizationMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
SixLabors.ImageSharp.Web.Middleware.ImageSharpMiddleware.Invoke(HttpContext httpContext, bool retry)
StackExchange.Profiling.MiniProfilerMiddleware.Invoke(HttpContext context) in MiniProfilerMiddleware.cs
Umbraco.Cms.Web.Common.Middleware.UmbracoRequestMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
Umbraco.Cms.Web.Common.Middleware.UmbracoRequestMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
Microsoft.AspNetCore.Builder.UseMiddlewareExtensions+<>c__DisplayClass6_1+<<UseMiddlewareInterface>b__1>d.MoveNext()
Umbraco.Cms.Web.Common.Middleware.PreviewAuthenticationMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
Microsoft.AspNetCore.Builder.UseMiddlewareExtensions+<>c__DisplayClass6_1+<<UseMiddlewareInterface>b__1>d.MoveNext()
Umbraco.Cms.Web.Common.Middleware.UmbracoRequestLoggingMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
Microsoft.AspNetCore.Builder.UseMiddlewareExtensions+<>c__DisplayClass6_1+<<UseMiddlewareInterface>b__1>d.MoveNext()
Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

It doesn't matter if we use typed return or just toList(). Same exception:

var test = Umbraco.ContentAtXPath("//home").OfType<Home>().ToList();

In our case the documentTypes are using nested contents and dropdowns in element type fields. If we change the data type to something else than dropdowns it works. And it does not matter what values your dropdown has, it's crashing.

Btw, is it planned to switch to System.Text.Json instead of NewtonSoft?

Specifics

No response

Steps to reproduce

1. create document types and element types.
2. within the element types use dropdown for a field, and create one dropdown with some items in it.
3. use the element type in your document type.
4. create a page using that document type
5. add values in the page for the dropdown field of the nested content item
6. in the corresponding .cshtml file use var test = Umbraco.ContentAtXPath("//yourType").ToList();

Expected result / actual result

No response

[github-actions[bot]]

Hi there @deekoulos!

Firstly, a big thank you for raising this issue. Every piece of feedback we receive helps us to make Umbraco better.

We really appreciate your patience while we wait for our team to have a look at this but we wanted to let you know that we see this and share with you the plan for what comes next.

• We'll assess whether this issue relates to something that has already been fixed in a later version of the release that it has been raised for.
• If it's a bug, is it related to a release that we are actively supporting or is it related to a release that's in the end-of-life or security-only phase?
• We'll replicate the issue to ensure that the problem is as described.
• We'll decide whether the behavior is an issue or if the behavior is intended.

We wish we could work with everyone directly and assess your issue immediately but we're in the fortunate position of having lots of contributions to work with and only a few humans who are able to do it. We are making progress though and in the meantime, we will keep you in the loop and let you know when we have any questions.

Thanks, from your friendly Umbraco GitHub bot :robot: :slightly_smiling_face: