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How do I make the code card not require a connection to the database?

Question:
How do I make the code card not require a connection to the database?
Description
I'm trying to figure out the project.
I built a code map.
When I click on a project on the code map, I get an error.
I use: Visual Studio-2022 Enterprise
Error:
The XML content of this document cannot be represented as a graph because it contains unexpected errors. Open the XML editor to fix these errors and try to reopen the graph.
The detected error is described below.
Unable to connect to the specified database.
An exception occurred or an attempt was made to connect to the database using the following connection string:
Data Source=(Local)\MSSQLLocalDB;AttachDbFilename=;Initial Catalog=master;Integrated Security=True;Enlist=False;Asynchronous Processing=True;MultipleActiveResultSets=True;Connect Timeout=30.
Verify that the specified instance of SQL Server exists and the service is running.
Call Stack:
in Microsoft.Repository.SqlInteraction.OpenAndConfigureConnection(SqlConnection connection)
in Microsoft.Repository.SqlInteraction.<>c__DisplayClass7_0.b__0()
in Microsoft.Repository.SqlInteraction.ExecuteRepositoryAction(Action action)
in Microsoft.Repository.SqlInteraction.UsingMasterConnection(String connectionString, Action`1 act)
in Microsoft.Repository.Utilities.GetDbStateAndFileNames(SqlConnectionStringBuilder builder)
in Microsoft.Repository.Utilities.GetDatabaseState(String connectionString)
in Microsoft.VisualStudio.ArchitectureTools.ProgressiveReveal.PRUtilities.CanQuery(ActionContext context, IProgressionCacheSettings settings)
in Microsoft.VisualStudio.ArchitectureTools.ProgressiveReveal.GetRepositoryTimestampsCommand.Execute(ActionContext context, IGraphStatus statusReporter, IProgressionCacheSettings settings)
in Microsoft.VisualStudio.Progression.ActionManager.CallNormalActions(Action action, ActionContext actionContext, Boolean propagateCancellation)
Pictures:
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Nesper - LoaderExceptions

I am building a Nesper application and after deployment it throws this error:
System.Reflection.ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.
at System.Reflection.RuntimeModule.GetTypes(RuntimeModule module)
at System.Reflection.RuntimeModule.GetTypes()
at System.Reflection.Assembly.GetTypes()
at com.espertech.esper.script.ScriptingServiceImpl.DiscoverEngines(Assembly assembly, Predicate`1 isEngine)
at com.espertech.esper.script.ScriptingServiceImpl.DiscoverEngines(Predicate`1 isEngine)
at com.espertech.esper.core.service.EPServicesContextFactoryDefault.CreateServicesContext(EPServiceProvider epServiceProvider, ConfigurationInformation configSnapshot)
at com.espertech.esper.core.service.EPServiceProviderImpl.DoInitialize(Nullable`1 startTime)
at com.espertech.esper.core.service.EPServiceProviderImpl..ctor(Configuration configuration, String engineURI, IDictionary`2 runtimes)
at com.espertech.esper.client.EPServiceProviderManager.GetProvider(String providerURI, Configuration configuration)

After I printed the LoaderExceptions, it shows that these two libraries are missing:
DevExpress.Printing.v13.2.Core
DevExpress.Sparkline.v13.2.Core

ResolutionFailedException with Unity

I'm using Patterns and Practices' Unity to inject dependencies into my objects and have hit a weird (to me, anyway) issue. Here's my class definitions:
public class ImageManager : IImageManager
{
IImageFileManager fileManager;
public ImageManager(IImageFileManager fileMgr)
{
this.fileManager = fileMgr;
}
}
public class ImageFileManager : IImageFileManager
{
public ImageFileManager(string folder)
{
FileFolder = folder;
}
}
And here's the code to register my classes
container.RegisterInstance<MainWindowViewModel>(new MainWindowViewModel())
.RegisterType<IPieceImageManager, PieceImageManager>(
new InjectionConstructor(typeof(string)))
.RegisterType<IImageFileManager, ImageFileManager>()
.RegisterType<IImageManager, ImageManager>(
new InjectionConstructor(typeof(IImageFileManager)));
I originally resolved this in the code behind (I know, it defeats the purpose. Bear with me.) of the XAML file like this
IImageManager imageManager = MvvmViewModelLocator.Container.Resolve<IImageManager>(
new ParameterOverride("folder", "/images"));
And it worked. But I created a view model for my main view and when I copied the same line into it, I get an exception. Here are the two most inner exceptions:
InnerException: Microsoft.Practices.Unity.ResolutionFailedException
HResult=-2146233088
Message=Resolution of the dependency failed, type = "SwapPuzzleApp.Model.IImageManager", name = "(none)".
Exception occurred while: while resolving.
Exception is: InvalidOperationException - The type IImageManager does not have an accessible constructor.
At the time of the exception, the container was:
Resolving SwapPuzzleApp.Model.IImageManager,(none)
Source=Microsoft.Practices.Unity
TypeRequested=IImageManager
StackTrace:
at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object existing, String name, IEnumerable`1 resolverOverrides)
at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, String name, IEnumerable`1 resolverOverrides)
at Microsoft.Practices.Unity.UnityContainer.Resolve(Type t, String name, ResolverOverride[] resolverOverrides)
at Microsoft.Practices.Unity.UnityContainerExtensions.Resolve[T](IUnityContainer container, ResolverOverride[] overrides)
at SwapPuzzleApp.ViewModel.MainWindowViewModel..ctor() in c:\Users\Carole\Documents\Visual Studio 2012\Projects\SwapPuzzle\SwapPuzzle\ViewModel\MainWindowViewModel.cs:line 17
at SwapPuzzleApp.ViewModel.MvvmViewModelLocator..cctor() in c:\Users\Carole\Documents\Visual Studio 2012\Projects\SwapPuzzle\SwapPuzzle\ViewModel\MvvmViewModelLocator.cs:line 51
InnerException: System.InvalidOperationException
HResult=-2146233079
Message=The type IImageManager does not have an accessible constructor.
Source=Microsoft.Practices.Unity
StackTrace:
StackTrace:
at Microsoft.Practices.ObjectBuilder2.DynamicMethodConstructorStrategy.ThrowForNullExistingObject(IBuilderContext context)
at lambda_method(Closure , IBuilderContext )
at Microsoft.Practices.ObjectBuilder2.DynamicBuildPlanGenerationContext.<>c__DisplayClass1.<GetBuildMethod>b__0(IBuilderContext context)
at Microsoft.Practices.ObjectBuilder2.DynamicMethodBuildPlan.BuildUp(IBuilderContext context)
at Microsoft.Practices.ObjectBuilder2.BuildPlanStrategy.PreBuildUp(IBuilderContext context)
at Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context)
at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object existing, String name, IEnumerable`1 resolverOverrides)
InnerException:
I'm not sure what the problem is, as ImageManager clearly has a public constructor. I thought it might be due to an invalid path, but if I concretely instantiate the object, everything works.
// this line has no problems
IImageManager imageManager = new ImageManager(new ImageFileManager("/images"));
I also wondered if I needed to pass in new InjectionConstructor(typeof(string)) when I register IImageManager, but it doesn't seem to help and why would it be needed now and not before? So I'm stumped. This is my first attempt at using Dependency Injection, so it's probably something basic. I'm just not seeing what, though.

Look very closely at the error message. Notice this part:
Message=The type IImageManager does not have an accessible constructor.
Notice the type name is IImageManager, not ImageManager. Somewhere along the line you lost your type mapping.
Your registration of FileImageManager has a problem as well, since you don't specify the folder parameter in the registration, so Unity has no idea what string to pass.

I was using the examples in this article as my guide. Either the examples in there are way too advanced for an introduction, or there's misinformation in that topic.
After consulting other sources (mainly PluarlSight), I came up with a much simpler and more logical solution.
container.RegisterInstance<TimerViewModel>(new TimerViewModel());
container.RegisterType<IPieceImageManager, PieceImageManager>();
container.RegisterType<IImageFileManager, ImageFileManager>
(new InjectionConstructor("/images"));
container.RegisterType<IImageManager, ImageManager>();

I ran into a similar issue with this error tied directly to a Mock (using automoq) that I was doing for an operation. In this case it turned out that because there were a number of member methods that get called with the object being mocked, that I had to define all of those in the automoq chain to get it to resolve properly
I realize this is an example in instance code, but it could occur in Moqs also. So if you read this and are wondering about an example related to Moqs, look into that first.

Linq- Random Item with same key has already been added Error

I am getting error "An item with the same key has already been added." I get this error randomly when many user try to access the same page on site in production at the same time.
In the code docid is passed and relevant help is displayed to user. As each user is viewing the same page so same ID is passed for all users. There is no insert operation in this call
Stack trace and souce code of mentioned line is given as follows
public string DocDescription(int docid)
{
DocumentRepository _Documentrepository = new DocumentRepository();
return _Documentrepository.GetDocDescription(docid);
}
}
public string GetDocDescription(int DocID)
{
if (DocID != 0)
return db.sysDocuments.SingleOrDefault(p => p.DocumentID == DocID).Description==null?"No Description Available":db.sysDocuments.SingleOrDefault(p => p.DocumentID == DocID).Description;
else
return "No Description Available";
}
Stack Trace excerpt:
System.Web.HttpException (0x80004005): Error executing child request for handler 'System.Web.Mvc.HttpHandlerUtil+ServerExecuteHttpHandlerWrapper'. ---> System.Web.HttpUnhandledException (0x80004005): Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> System.Web.HttpException (0x80004005): Error executing child request for handler 'System.Web.Mvc.HttpHandlerUtil+ServerExecuteHttpHandlerAsyncWrapper'. ---> System.ArgumentException: An item with the same key has already been added.
at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
at System.Data.Linq.DataContext.GetTable(MetaTable metaTable)
at System.Data.Linq.DataContext.GetTable[TEntity]()
at UserManagement.Models.DocumentRepository.GetDocDescription(Int32 DocID) in D:\Myproj\UserManagement\UserManagement\Models\DocumnetRepository.cs:line 109
at lambda_method(Closure , ControllerBase , Object[] )
at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters)
at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
at Castle.Proxies.ControllerActionInvokerProxy.InvokeActionMethod_callback(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at Castle.Proxies.Invocations.ControllerActionInvoker_InvokeActionMethod.InvokeMethodOnTarget()
at Castle.DynamicProxy.AbstractInvocation.Proceed()
at Glimpse.Net.Interceptor.InvokeActionMethodInterceptor.Intercept(IInvocation invocation)
at Castle.DynamicProxy.AbstractInvocation.Proceed()

From your code and comments, I get that you store db context in a static variable. This is generally a bad idea when working with entities.
DbContext is not thread safe. So, multiple users working with your site will cause such errors in context.
The general suggestion for working with context is to prefer short lived context. So just create a new instance, when you need it, and then forget it. For the web sites, it is quite common to use inversion of control container like Unity, Castle.Winsdor etc, and configure it to return one instance per web request for your DbContext. This will give you enough performance, so all entities needed for the current request are cached, and will not cause threading issues at the same time.

See comment too, static members are application scoped variables thus they're sharing the same dictionary which can throw errors like this if multiple requests add the same key.

DotNetNuke Action Menu Error

I'm using DotNetNuke 5.3. I add one menu item in ModuleActionCollection. Then I add this page to Module definition also. But I got this error:
Error: is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException:
Object reference not set to an
instance of an object. --->
System.NullReferenceException: Object
reference not set to an instance of an
object. at
DotNetNuke.UI.Modules.ModuleHost.LoadModuleControl()
--- End of inner exception stack trace

Are you using the ModuleActions property from the IActionable interface? Can you attach a debugger to that property and see if the NullReferenceException is happening in there? If you remove the IActionable interface from the module, does that get rid of the error?
Can you provide your implementation of ModuleActions?