Hi,

We are implementing usage of ExamineX in Umbraco v9, but upon the call to CreateQuery("content") an NPE occurs, stating the fields parameter is null.

IQuery query = index.Searcher.CreateQuery(IndexTypes.Content);

call stack:

System.ArgumentNullException: Value cannot be null. (Parameter 'fields')
   at ExamineX.AzureSearch.AzureSearchQuery.A(IReadOnlyList`1 , String )
   at ExamineX.AzureSearch.AzureSearchQuery..ctor(SearchClient indexClient, ILoggerFactory loggerFactory, String analyzer, String category, AzureSearchFieldReferences fields, BooleanOperation occurance)
   at ExamineX.AzureSearch.AzureSearchSearcher.CreateQuery(String category, BooleanOperation defaultOperation)
   at Umb.Platform.Web.Core.Controller.ActueelPageController.Init(ActueelPageModel lhs, IPublishedContent rhs, HttpRequest request) in C:\disk\d\dev\umb.platform\Umb.Platform.Web.Core\Controller\ActueelPageController.cs:line 123
   at Umb.Platform.Web.Core.Controller.ActueelPageController.Index() in C:\disk\d\dev\umb.platform\Umb.Platform.Web.Core\Controller\ActueelPageController.cs:line 200
   at lambda_method289(Closure , Object , Object[] )
   at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.SyncActionResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeActionMethodAsync>g__Logged|12_1(ControllerActionInvoker invoker)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeNextActionFilterAsync>g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextExceptionFilterAsync>g__Awaited|25_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ExceptionContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeNextResourceFilter()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Logged|17_1(ResourceInvoker invoker)
   at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
   at Umbraco.StorageProviders.AzureBlob.AzureBlobFileSystemMiddleware.HandleRequestAsync(HttpContext context, RequestDelegate next)
   at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
--- End of stack trace from previous location ---
   at Umbraco.Cms.Web.Common.Middleware.BasicAuthenticationMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
   at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
--- End of stack trace from previous location ---
   at Umbraco.Cms.Web.BackOffice.Middleware.BackOfficeExternalLoginProviderErrorMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
   at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Builder.Extensions.MapMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Session.SessionMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Session.SessionMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Localization.RequestLocalizationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
   at SixLabors.ImageSharp.Web.Middleware.ImageSharpMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.StatusCodePagesMiddleware.Invoke(HttpContext context)
   at StackExchange.Profiling.MiniProfilerMiddleware.Invoke(HttpContext context) in C:\projects\dotnet\src\MiniProfiler.AspNetCore\MiniProfilerMiddleware.cs:line 121
   at Umbraco.Cms.Web.Common.Middleware.UmbracoRequestMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
   at Umbraco.Cms.Web.Common.Middleware.UmbracoRequestMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
   at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
--- End of stack trace from previous location ---
   at Umbraco.Cms.Web.Common.Middleware.PreviewAuthenticationMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
   at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
--- End of stack trace from previous location ---
   at Umbraco.Cms.Web.Common.Middleware.UmbracoRequestLoggingMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
   at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

https://github.com/SDKits/ExamineX/issues/51