uncaught exception: Parent entity is not in the parent entity set for this association.

Question

User299698256 posted

I am getting this uncaught exception: Parent entity is not in the parent entity set for this association. using upshotjs. I think the problem is that even though i declare my data model is not matching or binded to the metadata model.

I have something like this in my ViewModel

UserModel ={

CountryModel

LanguageModel

}

        var dataSourceOptions = {
            providerParameters: { url: options.serviceUrl, operationName: "GetUsers" },
            entityType: entityType,
            bufferChanges: true,
            mapping: MyApp.User
        };
        var editorDataSource = new upshot.RemoteDataSource(dataSourceOptions);

        var countriesDataSource = new upshot.RemoteDataSource({
            providerParameters: { url: options.serviceUrl, operationName: "GetCountryOptionsForUser", operationParameters: parentEntitiesOperationParameters },
            entityType: "Country:#MyApp.Core.Entities",
            dataContext: editorDataSource.getDataContext()
        });

the countriesDataSource gets all the countries and languages.

CountryModel={

Name

Languages <- Array of Language Models

}

If I supply the dataContext option then this is not a problem but I have another model inside the Country Model call Languages and this Language model is not binded or mapped to the one supplyed by the metadata model. How can I bind the raw data to the DataSource? I try using the editorDataSource.getDataContext().addMapping(MyApp.Language.Type, MyApp.Language) but this does not seem to work.

Answer 1

User1364817430 posted

The mapping must represent the data you get back from the service. If you retrieve your data from the server it's always an IQueryable of a certain type. The complete model of this type must recreated in a JS object, then this object can be mapped an represent your object(s) you get back from the server. In your case i think you have only mapped one of the child objects.

greetings

Kristof

Answer 2

User299698256 posted

could you please explain how to map my child objects. As I understand when you fetch data using RemoteDataSource and if you supply the mapping model then I thought it would automatically mapped all the child objects as well.

Answer 3

User1364817430 posted

Hi,

You can do this as follow:

function TodoItem(properties) {
   var self = this;
   properties = properties || {};
   self.TodoItemId = ko.observable(properties.TodoItemId || 0);
   self.Title = ko.observable(properties.Title);
   self.IsDone = ko.observable(properties.IsDone);
   // Added for updating entities.
   upshot.map(properties, "TodoItem:#Ria4HTMLWithoutSPA.Models", self); // Add properties from the server. 
   upshot.addEntityProperties(self); // add properties managed by upshot
};

For more info you can take a look at my sample application http://ria4htmldemo.codeplex.com/

Greetings

Kristof

 

Answer 4

User299698256 posted

yes i understand that part. The problem here and i think is a bug or something is that when you get the Json from the server it gets a __type: property with upshot and i think upshot need this __type to bind the model but the problem is that if you have class as below:

[DataContract(Name = "Country")]

public class CountryViewModel()

{

[Key]

[DataMember]

public int Id {get;set;}

[DataMember]

public string Name {get;set;}

[DataMember]

public IEnumerable<Language> Languages {get;set;}

}

[DataContract(Name = "Language")]

public class LanguageViewModel()

{

[Key]

[DataMember]

public int Id {get;set;}

[DataMember]

public string Name {get;set;}

}

If you do a remotedataaccess then this would fetch a json data something like this :

{"Results":[
{"__type":"Country:MyApp.Core.Entities",
"Id":1,
"Languages":[{"Id":1,"Name":"English"},
{"Id":2,"Name":"Spanish"}],"Name":"USA"}
}],
"TotalCount":1}

This data when binded, upshot only knows the one with the __type Model and but for the Language model it does not have the __type so it does not bind properly. How can I get the __type on the Languages property?

Answer 5

User1364817430 posted

I think the problem you are struggling with is:

you need to provide the metadata of your objects. If you use Steven Sandersons demo, you can use the following line of code:

@(Html.UpshotContext(bufferChanges: true).DataSource<DataServiceController>(x => x.MethodToRetrieveData())) 

This will configure the metadata u need and configure upshot for you.

Take a look what it generates, and then you can use it manually if you want to.

greetings

Kristof