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New Comment on "T4RIA Documentation"

valeriuz — Fri, 24 May 2013 08:56:52 GMT

How to use GeneratedMetadataProvider and attributes on client side?

Updated Wiki: EntityTools

ColinBlair — Thu, 23 Aug 2012 18:53:22 GMT

Description

EntityTools is modeled after Silverlight Contrib/Silverlight Extensions. It currently has a library of extentions for the Entity and EntitySet which provide data import and export abilities.

Documentation

Online documentation can be found at http://www.riaservicesblog.net/RiaServicesContrib.EntityTools
Offline documentation is available at http://www.riaservicesblog.net/RiaServicesContrib.EntityTools/Entity%20Tools.chm

Examples

Entity cloning

Person newPerson = newPerson();
newPerson.ApplyState(Nothing, existingPerson.ExtractState(ExtractType.ModifiedState);
newPerson.PersonId = Guid.NewGuid();
context.Persons.Add(newPerson);

Partial Save (i.e. save only a single change instead of the whole DomainContext)

PersonDomainContext tempContext = new PersonDomainContext();
Person savePerson = newPerson();
tempContext.Persons.Add(savePerson);
savePerson.ApplyState(originalPerson.ExtractState(ExtractType.OriginalState, ExtractType.ModifiedState);
tempContext.SubmitChanges();

A more powerful example of performing a partial save can be found at http://riaservicescontrib.codeplex.com/wikipage?title=PartialSaveWithEntityGraph&referringTitle=EntityGraphs%20

Export EntityList and save to Isolated Storage

using IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication()
{
    using IsolatedStorageFileStream isfs = new IsolatedStorageFileStream(fileName, FileMode.OpenOrCreate, isf)
    {
        DataContractSerializer serializer = new DataContractSerializer(typeof(List<EntityStateSet>));
        serializer.WriteObject(isfs, context.Persons.Export());
        isfs.Close();
    }
}

Import information from Isolated Storage into EntityList

using IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication()
{
    using IsolatedStorageFileStream isfs = new IsolatedStorageFileStream(fileName, FileMode.Open, isf)
    {
        DataContractSerializer serializer = new DataContractSerializer(typeof(List<EntityStateSet>));
        context.Persons.Import(serializer.ReadObject(isfs));
        isfs.Close();
    }
}

Some things which might not be obvious is that the Export functionality can also be done against a LINQ query, allowing partial exports of entities.

Updated Wiki: FluentMetadata for WCF RIA Services

MdeJ — Tue, 05 Jun 2012 12:21:26 GMT

FluentMetadata, a Fluent API for defining metadata for WCF RIA Services entities

With permission of Nikhil Kothari, I've added the source code of Nikhil's Fluent API for defining WCF Ria Services Metadata to RIA Services Contrib. I've made a couple of changes. Most noticeable is the ability to attach a MetadataClass to your domain service using the FluentMetadata attribute. This class mimics the OnModelCreating method in EntityFramework DbContext and allows you to instantiate your Metadata classes. The original version is available here.

The main advantage of this package is that it allows you to separate your datamodel and metadata in separate projects/assemblies. This is not possible with the standard RIA services approach of buddy classes. These have to be defined in the same project as your datamodel. The drawbacks of this are a pollution of your datamodel and (most importantly) that your datamodel project becomes dependent on RIA services-specific assemblies. With the FluentMetadata package you can define metadata in any assembly you like.

Download: the package is available as a Nuget package.

Changes in version 0.2.69239.0

The fluent API now supports defining associations, e.g.

metadataContainer.Entity<Bar>()
    .Projection(x => x.FooSet)
        .Association()
            .WithName("MyAssociation")
            .WithThisKey(x => x.Id2, x=>x.Id)
            .WithOtherKey(x => x.Id2, x=>x.Id);

Metadata can be defined in a Metadata class per type or directly in your IFluentMetadataConfiguration
The Fluent API is more open such that it can be extended in third-party libraries

Using FluentMetadata

Install the FluentMetadata Nuget package (or download its source code)
Define a MetadataConfiguration class containing the fluent metadata for your entities. For example:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Entity<Foo>().Projection(x => x.SomeProperty).Exclude();
    }
}

Alternatively, you can define the metadat for each entity in separate MetadataClass classes. For example

public class FooMetadata : MetadataClass<Foo>
{
    public FooMetadata()
    {
        this.Projection(x => x.ExcludedString).Exclude();
        this.Validation(x => x.RequiredString).Required();
        this.Validation(x => x.RegularExpressionString).RegularExpression("[a-z]");
    }
}

... and instantiate it from your FluentMetadataConfiguration class, like so:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Add(new FooMetadata());
    }
}

... both mechanisms can be combined.
Lastly, add the FluentMetadata attribute to your domain service:

[EnableClientAccess()]
[FluentMetadata(typeof(FluentMetadataConfiguration))]
public class FluentMetadataTestDomainService : DomainService
{
}

Updated Wiki: FluentMetadata for WCF RIA Services

MdeJ — Mon, 04 Jun 2012 20:48:59 GMT

FluentMetadata, a Fluent API for defining metadata for WCF RIA Services entities

The fluent API now supports defining associations
Metadata can be defined in a Metadata class per type or directly in your IFluentMetadataConfiguration
The Fluent API is more open such that it can be extended in third-party libraries

To make use of FluentMetadata:

Install the FluentMetadata Nuget package (or download its source code)
Define a MetadataConfiguration class containing the fluent metadata for your entities. For example:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Entity<Foo>().Projection(x => x.SomeProperty).Exclude();
    }
}

Alternatively, you can define the metadat for each entity in separate MetadataClass classes. For example

public class FooMetadata : MetadataClass<Foo>
{
    public FooMetadata()
    {
        this.Projection(x => x.ExcludedString).Exclude();
        this.Validation(x => x.RequiredString).Required();
        this.Validation(x => x.RegularExpressionString).RegularExpression("[a-z]");
    }
}

... and instantiate it from your FluentMetadataConfiguration class, like so:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Add(new FooMetadata());
    }
}

... both mechanisms can be combined.
Lastly, add the FluentMetadata attribute to your domain service:

[EnableClientAccess()]
[FluentMetadata(typeof(FluentMetadataConfiguration))]
public class FluentMetadataTestDomainService : DomainService
{
}

Updated Wiki: FluentMetadata for WCF RIA Services

MdeJ — Mon, 04 Jun 2012 20:45:42 GMT

FluentMetadata, a Fluent API for defining metadata for WCF RIA Services entities

Install the FluentMetadata Nuget package (or download its source code)
Define a MetadataConfiguration class containing the fluent metadata for your entities. For example:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Entity<Foo>().Projection(x => x.SomeProperty).Exclude();
    }
}

Alternatively, you can define the metadat for each entity in separate MetadataClass classes. For example

public class FooMetadata : MetadataClass<Foo>
{
    public FooMetadata()
    {
        this.Projection(x => x.ExcludedString).Exclude();
        this.Validation(x => x.RequiredString).Required();
        this.Validation(x => x.RegularExpressionString).RegularExpression("[a-z]");
    }
}

... and instantiate it from your FluentMetadataConfiguration class, like so:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Add(new FooMetadata());
    }
}

... both mechanisms can be combined.
Lastly, add the FluentMetadata attribute to your domain service:

[EnableClientAccess()]
[FluentMetadata(typeof(FluentMetadataConfiguration))]
public class FluentMetadataTestDomainService : DomainService
{
}

Updated Wiki: FluentMetadata for WCF RIA Services

MdeJ — Mon, 04 Jun 2012 20:23:16 GMT

FluentMetadata, a Fluent API for defining metadata for WCF RIA Services entities

With permission of Nikhil Kothari, I've added the source code of Nikhil's Fluent API for defining WCF Ria Services Metadata to RIA Services Contrib. I've made a couple of changes. Most noticeable is the ability to attach a MetadataClass to your domain service using the FluentMetadata attribute. This class mimics the OnModelCreating method in EntityFramework DbContext and allows you to instantiate your Metadata classes. The original version is available here.

The main advantage of this package is that it allows you to separate your datamodel and metadata in separate projects/assemblies. This is not possible with the standard RIA services approach of buddy classes. These have to be defined in the same project as your datamodel. The drawbacks of this are a pollution of your datamodel and (most importantly) that your datamodel project becomes dependent on RIA services-specific assemblies. With the FluentMetadata package you can define metadata in any assembly you like.

The package is also available as a Nuget package.

To make use of FluentMetadata:

Install the FluentMetadata Nuget package (or download its source code)
Define a MetadataConfiguration class containing the fluent metadata for your entities. For example:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Entity<Foo>().Projection(x => x.SomeProperty).Exclude();
    }
}

Alternatively, you can define the metadat for each entity in separate MetadataClass classes. For example

public class FooMetadata : MetadataClass<Foo>
{
    public FooMetadata()
    {
        this.Projection(x => x.ExcludedString).Exclude();
        this.Validation(x => x.RequiredString).Required();
        this.Validation(x => x.RegularExpressionString).RegularExpression("[a-z]");
    }
}

... and instantiate it from your FluentMetadataConfiguration class, like so:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Add(new FooMetadata());
    }
}

... both mechanisms can be combined.
Lastly, add the FluentMetadata attribute to your domain service:

[EnableClientAccess()]
[FluentMetadata(typeof(FluentMetadataConfiguration))]
public class FluentMetadataTestDomainService : DomainService
{
}

Updated Wiki: Documentation

MdeJ — Sun, 25 Mar 2012 20:22:54 GMT

For documentation about the features of WVF RIA Services Contrib click on one of the links below:

* ComboBoxExtensions
* Data Validation Framework
* Entity Tools
* EntityGraph
* FluentMetadata for WCF RIA Services
* T4RIA

Updated Wiki: Documentation

MdeJ — Sun, 25 Mar 2012 20:21:09 GMT

Updated Wiki: Home

MdeJ — Sun, 25 Mar 2012 20:20:26 GMT

Project Description

WCF RIA Services Contrib is a collection of tools for WCF RIA Services. Contributions are welcome.

WCF RIA Services Contrib has the following features:

ComboBoxExtensions	Is a collection of extensions to ComboBox that add asynchronous loading, cascading ComboBoxes and support for Entity associations to ComboBoxes.
Data Validation Framework	Is a generic validation framework that is much more flexible and feature-rich than the validation framework of WCF RIA Services.
Entity Tools	Is a collection of extension methods that add state manipulation functionality (such as cloning) to entities.
EntityGraph	Is a technology to separate generic operations (such as cloning iterating, validation) from your data model.
FluentMetadata	A Fluent API for defining metadata for WCF RIA Services entities.
T4RIA	is a T4 template that generates domain services, metadata and localization for WCF RIA Services from ADO.NET Entity Data Model.

Download and install

WCF RIA Services is available in the following forms:

Source code. If you need the most recent stuff of WCF RIA Services Contrib, or if you want to make (and contribute) your own changes, checking out the source code here is the way to go.
NuGet. This is the prefered way of using WCF RIA Services Contrib because it allows you to use only those parts that you need, because installation is very simple, and because most NuGet packages are released more frequently then the binary release of WCF RIA Services Contrib, described below. The following sub-components of WCF RIA Services Contrib are distributed as NuGet Packages:
Binary zip file. This bundles EntityTools, ComboBoxExtensions, and T4RIA. You can obtain this distribution via the Downloads tab. The zip file is no longer being maintained.

Please Contribute

If you have any RIA Services related code which you would like to add to this project please let me know. I welcome anyone willing to contribute.

Updated Wiki: FluentMetadata for WCF RIA Services

MdeJ — Sun, 25 Mar 2012 20:19:49 GMT

FluentMetadata, a Fluent API for defining metadata for WCF RIA Services entities

With permission of Nikhil Kothari, I've added the source code of Nikhil's Fluent API for defining WCF Ria Services Metadata to RIA Services Contrib. I've made a couple of changes. Most noticeable is the ability to attach a MetadataClass to your domain service using the FluentMetadata attribute. This class mimics the OnModelCreating method in EntityFramework DbContext and allows you to instantiate your Metadata classes. The original version is available here.

The main advantage of this package is that it allows you to separate your datamodel and metadata in separate projects/assemblies. This is not possible with the standard RIA services approach of buddy classes. These have to be defined in the same project as your datamodel. The drawbacks of this are a pollution of your datamodel and (most importantly) that you datamodel project becomes dependent on RIA services-specific assemblies. With the FluentMetadata package you can define metadata in any assembly you like.

The package is also available as a Nuget package.

To make use of FluentMetadata:

Install the FluentMetadata Nuget package (or download its source code)
Define metadata classes for your entities (this is pretty similar to EntityFramework). For example:

public class FooMetadata : MetadataClass<Foo>
{
    public FooMetadata()
    {
        this.Projection(x => x.ExcludedString).Exclude();
        this.Validation(x => x.RequiredString).Required();
        this.Validation(x => x.RegularExpressionString).RegularExpression("[a-z]");
    }
}

Define a MetadataConfiguration class that instantiates all your metadata classes. For example:

public class FluentMetadataConfiguration : IFluentMetadataConfiguration
{
    public void OnTypeCreation(MetadataContainer metadataContainer)
    {
        metadataContainer.Add(new FooMetadata());
    }
}

Add the FluentMetadata attribute to your domain service:

[EnableClientAccess()]
[FluentMetadata(typeof(FluentMetadataConfiguration))]
public class FluentMetadataTestDomainService : DomainService
{
}

Updated Wiki: Home

ColinBlair — Tue, 14 Feb 2012 16:01:17 GMT

Project Description

WCF RIA Services Contrib is a collection of tools for WCF RIA Services. Contributions are welcome.

WCF RIA Services Contrib has the following features:

ComboBoxExtensions	Is a collection of extensions to ComboBox that add asynchronous loading, cascading ComboBoxes and support for Entity associations to ComboBoxes.
Data Validation Framework	Is a generic validation framework that is much more flexible and feature-rich than the validation framework of WCF RIA Services.
Entity Tools	Is a collection of extension methods that add state manipulation functionality (such as cloning) to entities.
EntityGraph	Is a technology to separate generic operations (such as cloning iterating, validation) from your data model.
FluentMetadata	A package that enables to define metadata for entities using a Fluent API.
T4RIA	is a T4 template that generates domain services, metadata and localization for WCF RIA Services from ADO.NET Entity Data Model.

Download and install

WCF RIA Services is available in the following forms:

Source code. If you need the most recent stuff of WCF RIA Services Contrib, or if you want to make (and contribute) your own changes, checking out the source code here is the way to go.
NuGet. This is the prefered way of using WCF RIA Services Contrib because it allows you to use only those parts that you need, because installation is very simple, and because most NuGet packages are released more frequently then the binary release of WCF RIA Services Contrib, described below. The following sub-components of WCF RIA Services Contrib are distributed as NuGet Packages:
Binary zip file. This bundles EntityTools, ComboBoxExtensions, and T4RIA. You can obtain this distribution via the Downloads tab. The zip file is no longer being maintained.

Please Contribute

If you have any RIA Services related code which you would like to add to this project please let me know. I welcome anyone willing to contribute.

Updated Wiki: Home

MdeJ — Thu, 01 Dec 2011 10:38:59 GMT

Project Description

WCF RIA Services Contrib is a collection of tools for WCF RIA Services. Contributions are welcome.

WCF RIA Services Contrib has the following features:

ComboBoxExtensions	Is a collection of extensions to ComboBox that add asynchronous loading, cascading ComboBoxes and support for Entity associations to ComboBoxes.
Data Validation Framework	Is a generic validation framework that is much more flexible and feature-rich than the validation framework of WCF RIA Services.
Entity Tools	Is a collection of extension methods that add state manipulation functionality (such as cloning) to entities.
EntityGraph	Is a technology to separate generic operations (such as cloning iterating, validation) from your data model.
FluentMetadata	A package that enables to define metadata for entities using a Fluent API.
T4RIA	is a T4 template that generates domain services, metadata and localization for WCF RIA Services from ADO.NET Entity Data Model.

Download and install

WCF RIA Services is available in the following forms:

Source code. If you need the most recent stuff of WCF RIA Services Contrib, or if you want to make (and contribute) your own changes, checking out the source code here is the way to go.
NuGet. This is the prefered way of using WCF RIA Services Contrib because it allows you to use only those parts that you need, because installation is very simple, and because most NuGet packages are released more frequently then the binary release of WCF RIA Services Contrib, described below. The following sub-components of WCF RIA Services Contrib are distributed as NuGet Packages:
Binary zip file. This bundles EntityTools, ComboBoxExtensions, and T4RIA. You can obtain this distribution via the Downloads tab.

Please Contribute

If you have any RIA Services related code which you would like to add to this project please let me know. I welcome anyone willing to contribute.

Updated Wiki: Home

MdeJ — Thu, 01 Dec 2011 10:14:12 GMT

Project Description

WCF RIA Services Contrib is a collection of tools for WCF RIA Services. Contributions are welcome.

WCF RIA Services Contrib has the following features:

ComboBoxExtensions	Is a collection of extensions to ComboBox that add asynchronous loading, cascading ComboBoxes and support for Entity associations to ComboBoxes.
Data Validation Framework	Is a generic validation framework that is much more flexible and feature-rich than the validation framework of WCF RIA Services.
Entity Tools	Is a collection of extension methods that add state manipulation functionality (such as cloning) to entities.
EntityGraph	Is a technology to separate generic operations (such as cloning iterating, validation) from your data model.
FluentMetadata	A package that enables to define metadata for entities using a Fluent API.
T4RIA	is a T4 template that generates domain services, metadata and localization for WCF RIA Services from ADO.NET Entity Data Model.

Download and install

WCF RIA Services is available in the following forms:

Source code. If you need the most recent stuff of WCF RIA Services Contrib, or if you want to make (and contribute) your own changes, checking out the source code here is the way to go.
NuGet. This is the prefered way of using WCF RIA Services Contrib because it allows you to use only those parts that you need, because installation is very simple, and because most NuGet packages are released more frequently then the binary release of WCF RIA Services Contrib, described below. The following sub-components of WCF RIA Services Contrib are distributed as NuGet Packages:
Binary zip file. This bundles EntityTools, ComboBoxExtensions, and T4RIA.

Please Contribute

If you have any RIA Services related code which you would like to add to this project please let me know. I welcome anyone willing to contribute.

Updated Wiki: PartialSaveWithEntityGraph

MdeJ — Thu, 01 Dec 2011 09:31:00 GMT

How to partially save entities in your domain context?

Introduction

A RIA services domain context is used to manage your entities and to submit changes to your domain service following the unit of work pattern. The domain context gives little or no control over what entities are going to be communicated to a domain service when the SubmitChanges() method is invoked. There are many situations where just submitting all pending changes is too coarse grained. In this post I will explain how EntityGraph can give control over which entities are submitted to your domain context (but see Disclaimer below).

EntityGraph in a Nutshell

An entity graph is defined as a collection of entities connected through their associations that forms a logical unit. An entity graph is defined by means of an entity graph shape. For example:

var shape = new EntityGraphShape()
   .Edge<Car, Wheel>(x => Wheels)
   .Edge<Car, Engine>(x => Engine);

This defines the shape of an entity graph spanning the associations between Car, its Wheels, and its Engine.

Given an Car instance called car, we can create a corresponding EntityGraph as follows:

var graph = new EntityGraph(car, shape);

There are many things you can now do with this entity graph. E.g., see http://riaservicescontrib.codeplex.com/wikipage?title=EntityGraphs.

For partial save I'm going to focus on the Clone() method. I.e., we can create a clone of car like this:

var clone = graph.Clone();

This example creates an identical copy of car and all entities that are reachable according to the edges in shape (i.e., it includes identical copies of the wheels and the engine of the car).

Implementing Partial Save

Lets assume that car is contained in the domain context CarExampleContext and that we want to submit the changes of this single Car instance together with its associated wheels and engine. This basically means that we want to submit only the pending changes for the entities contained in the entity graph we just created. Of course, we can't just call SubmitChanges() on the CarExampleContext because that may also submit pending changes of entities that are not part of the graph.

For a partial save of car, this is what we are going to do:

Create a new instance of CarExampleContext called partialSaveContext
Duplicate the entity graph for car in this new context
Call SubmitChanges() on partialSaveContext
On success, synchronize the entities in the original domain context with the entities in partialSaveContext.

A clone cannot be present in the same domain context as its source. The reason is that the cloned entities have the same primary keys. Adding them will lead to an exception indicating that an entity with the same key is already present in the context. The Clone() method that we used above therefore returns a cloned entity (and its associations) that is not attached to any domain context. A consequence is that the cloned entities no longer contain state information (since they are not managed by a context). They all have an EntityState of EntityState.Detached. Attaching them to partialSaveContext will give them an EntityState of EntityState.Unmodified. HasChanges will return false and calling SubmitChanges() will have no effect. This is clearly not what we have in mind for a partial save method.

In order to make a clone of car that includes proper state information, the cloned entities must be attached to a domain context. For this purpose, EntityGraph also provides a state-preserving Clone() method. It attaches the cloned entities to another context and restores the entity state. This is the method we're going to use:

var partialSaveContext = new CarExampleContext();
var clone = graph.Clone(partialSaveContext);

After calling Clone(), partialSaveContext will contain a clone of car and all entities in this domain context have the same EntityState as the entities in the entity graph graph. This means that partialSaveContext.HasChanges yields true and that we can now call SubmitChanges() on the context:

partialSaveContext.SubmitChanges();

This will submit the pending changes of the cloned entity graph rooted at car to the server. Nothing more, nothing less.

If SubmitChanges() completes without an error, you can verify that partialSaveContext.HasChanges yields false, as expected. However, the original context still has changes pending. This can be observed by inspecting context.HasChanges and graph.HasChanges. Both properties yield true. This is because the source domain context still contains the original entities with their changes pending. Moreover, since we've submitted the changes to the server, some of the properties of the entities in partialSaveContext may have been updated with server-provided values (this is for instance the case with generated keys). As a final step we therefore have to synchronize the entities in the original context with the entities in partialSaveContext. This can be done with the Synchronize method of EntityGraph:

graph.Synchronize(clone);

This updates the entities in the EntityGraph graph according to the entities in the EntityGraph clone. This includes updating the entity states. As a result, graph and clone are identical clones and both have no more pending changes (you can verify that all entities in graph have their EntityState set to EntityState.Unmodified, exactly what is needed. This completes the partial save mechanism. Observe that partialSaveContext is no longer needed.

Disclaimer

There is one situation where the partial save method will/can not work correctly. This happens when an entity falls out the entity graph because a foreign key of the entity is changed. For example, by removing a wheel from car:

var wheel = car.Wheels.First();
car.Wheels.Remove(wheel)

Changing the foreign key forms a change of the owning entity (wheel in the example). But since it is no longer part of the entity graph, its change will not be submitted to the server during a partial save. The result is that after a partial save, the original context still has pending changes. It is not obvious how to deal with this. Please let me know if you have a solution.

Updated Wiki: PartialSaveWithEntityGraph

MdeJ — Wed, 30 Nov 2011 21:09:28 GMT

How to partially save entities in your domain context?

Introduction

EntityGraph in a Nutshell

An entity graph is defined as a collection of entities connected through their associations that forms a logical unit. An entity graph is defined by means of an entity graph shape. For example:

var shape = new EntityGraphShape()
   .Edge<Car, Wheel>(x => Wheels)
   .Edge<Car, Engine>(x => Engine);

This defines the shape of an entity graph spanning the associations between Car, its Wheels, and its Engine.

Given an Car instance called car, we can create a corresponding EntityGraph as follows:

var graph = new EntityGraph(car, shape);

var clone = graph.Clone();

This example creates an identical copy of car and all entities that are reachable according to the edges in shape (i.e., it includes identical copies of the wheels and the engine of the car).

Implementing Partial Save

Create a new instance of CarExampleContext called partialSaveContext
Duplicate the entity graph for car in this new context
Call SubmitChanges() on partialSaveContext
On success, synchronize the entities in the original domain context with the entities in partialSaveContext.

var partialSaveContext = new CarExampleContext();
var clone = graph.Clone(partialSaveContext);

partialSaveContext.SubmitChanges();

graph.Synchronize(clone);

This updates the entities in the EntityGraph graph according to the entities in the EntityGraph clonedGraph. This includes updating the entity states. As a result, graph and clonedGraph are identical clones and both have no more pending changes (you can verify that all entities in graph have their EntityState set to EntityState.Unmodified, exactly what is needed. This completes the partial save mechanism. Observe that partialSaveContext is no longer needed.

Disclaimer

var wheel = car.Wheels.First();
car.Wheels.Remove(wheel)

Updated Wiki: PartialSaveWithEntityGraph

MdeJ — Tue, 29 Nov 2011 20:25:01 GMT

How to partially save entities in your domain context?

Introduction

EntityGraph in a Nutshell

An entity graph is defined as a collection of entities connected through their associations that forms a logical unit. An entity graph is defined by means of an entity graph shape. For example:

var shape = new EntityGraphShape()
   .Edge<Car, Wheel>(x => Wheels)
   .Edge<Car, Engine>(x => Engine);

This defines the shape of an entity graph spanning the associations between Car, its Wheels, and its Engine.

Given an Car instance called car, we can create a corresponding EntityGraph as follows:

var graph = new EntityGraph(car, shape);

var clone = graph.Clone();

This example creates an identical copy of car and all entities that are reachable according to the edges in shape (i.e., it includes identical copies of the wheels and the engine of the car).

Implementing Partial Save

Create a new instance of CarExampleContext called partialSaveContext
Duplicate the entity graph for car in this new context
Call SubmitChanges() on partialSaveContext
On success, synchronize the entities in the original domain context with the entities in partialSaveContext.

var partialSaveContext = new CarExampleContext();
var clone = graph.Clone(partialSaveContext);

partialSaveContext.SubmitChanges();

var clonedGraph =  new EntityGraph(clone, shape);
graph.Synchronize(clonedGraph);

Disclaimer

var wheel = car.Wheels.First();
car.Wheels.Remove(wheel)

New Comment on "PartialSaveWithEntityGraph"

joebrockhaus — Mon, 28 Nov 2011 21:11:37 GMT

I thought I overlooked something, but I can't find where the cloned entities had their newly updated states copied back onto the originals in the non-partial-save context?

Updated Wiki: PartialSaveWithEntityGraph

MdeJ — Mon, 28 Nov 2011 16:48:48 GMT

How to partially save entities in your domain context?

Introduction

EntityGraph in a Nutshell

An entity graph is defined as a collection of entities connected through their associations that forms a logical unit. An entity graph is defined by means of an entity graph shape. For example:

var shape = new EntityGraphShape()
   .Edge<Car, Wheel>(x => Wheels)
   .Edge<Car, Engine>(x => Engine);

This defines the shape of an entity graph spanning the associations between Car, its Wheels, and its Engine.

Given an Car instance called car, we can create a corresponding EntityGraph as follows:

var graph = new EntityGraph(car, shape);

var clone = graph.Clone();

This example creates an identical copy of car and all entities that are reachable according to the edges in shape (i.e., it includes identical copies of the wheels and the engine of the car).

Implementing Partial Save

Create a new instance of CarExampleContext called partialSaveContext
Duplicate the entity graph for car in this new context
Call SubmitChanges() on partialSaveContext
On success, accept the changes on the car entity graph in the orignal domain context.

var partialSaveContext = new CarExampleContext();
var clone = graph.Clone(partialSaveContext);

partialSaveContext.SubmitChanges();

This will submit the pending changes of the cloned entity graph rooted at car to the server. Nothing more, nothing less.

If SubmitChanges() completes without an error, you can verify that partialSaveContext.HasChanges yields false, as expected. However, the original context still has changes pending. This can be observed by inspecting context.HasChanges and graph.HasChanges. Both properties yield true. This is because the source domain context still contains the original entities with their changes pending. Since we've submitted the changes to the server, we should, as a final step, instruct context to just accept the pending changes on the entities in graph. This can be done using the System.ComponentModel.IChangeTracking interface that is defined on entities and on entity graphs:

graph.AcceptChanges()

This will set the EntityState of all entities in our entity graph to EntityState.Unmodified, exactly what is needed. This completes the partial save mechanism. Observe that partialSaveContext is no longer needed.

Disclaimer

var wheel = car.Wheels.First();
car.Wheels.Remove(wheel)

Updated Wiki: PartialSaveWithEntityGraph

MdeJ — Mon, 28 Nov 2011 16:42:38 GMT

How to partially save entities in your domain context?

Introduction

EntityGraph in a Nutshell

An entity graph is defined as a collection of entities connected through their associations that forms a logical unit. An entity graph is defined by means of an entity graph shape. For example:

var shape = new EntityGraphShape()
   .Edge<Car, Wheel>(x => Wheels)
   .Edge<Car, Engine>(x => Engine);

This defines the shape of an entity graph spanning the associations between Car, its Wheels, and its Engine.

Given an Car instance called car, we can create a corresponding EntityGraph as follows:

var graph = new EntityGraph(car, shape);

var clone = graph.Clone();

This example creates an identical copy of car and all entities that are reachable according to the edges in shape (i.e., it includes identical copies of the wheels and the engine of the car).

Implementing Partial Save

Create a new instance of CarExampleContext called partialSaveContext
Duplicate the entity graph for ar in this new context
Call SubmitChanges() on partialSaveContext
On success, accept the changes on the car entity graph in the orignal domain context.

var partialSaveContext = new CarExampleContext();
var clone = graph.Clone(partialSaveContext);

partialSaveContext.SubmitChanges();

This will submit the pending changes of the cloned entity graph rooted at car to the server. Nothing more, nothing less.

If SubmitChanges() completes without an error, you can verify that partialSaveContext.HasChanges yields false, as expected. However, the original context still has changes pending. This can be observed by inspecting context.HasChanges and graph.HasChanges. Both properties yield true. This is because the source domain context still contains the original entities with their changes pending. Since we've submitted the changes to the server, we should, as a final step, instruct context to just accept the pending changes on the entities in graph. This can be done using the System.ComponentModel.IChangeTracking interface that is defined on entities and on entity graphs:

graph.AcceptChanges()

Disclaimer

var wheel = car.Wheels.First();
car.Wheels.Remove(wheel)

Updated Wiki: PartialSaveWithEntityGraph

MdeJ — Mon, 28 Nov 2011 16:39:45 GMT

How to partially save entities in your domain context?

var shape = new EntityGraphShape()
   .Edge<Car, Wheel>(x => Wheels)
   .Edge<Car, Engine>(x => Engine);

This defines the shape of an entity graph spanning the associations between Car, its Wheels, and its Engine.

Given an Car instance called car, we can create a corresponding EntityGraph as follows:

var graph = new EntityGraph(car, shape);

var clone = graph.Clone();

This example creates an identical copy of car and all entities that are reachable according to the edges in shape (i.e., it includes identical copies of the wheels and the engine of the car).

Lets assume that car is contained in the domain context CarExampleContext and that we want to submit the changes of this single Car instance together with its associated wheels and engine. This basically means that we want to submit only the pending changes for the entities contained in the entity graph we just created. Of course, we can't just call SubmitChanges() on the CarExampleContext because that may also submit pending changes of entities that are not part of the graph.

For a partial save of car, this is what we are going to do:

Create a new instance of CarExampleContext called partialSaveContext
Duplicate the entity graph for ar in this new context
Call SubmitChanges() on partialSaveContext
On success, accept the changes on the car entity graph in the orignal domain context.

var partialSaveContext = new CarExampleContext();
var clone = graph.Clone(partialSaveContext);

partialSaveContext.SubmitChanges();

This will submit the pending changes of the cloned entity graph rooted at car to the server. Nothing more, nothing less.

If SubmitChanges() completes without an error, you can verify that partialSaveContext.HasChanges yields false, as expected. However, the original context still has changes pending. This can be observed by inspecting context.HasChanges and graph.HasChanges. Both properties yield true. This is because the source domain context still contains the original entities with their changes pending. Since we've submitted the changes to the server, we should, as a final step, instruct context to just accept the pending changes on the entities in graph. This can be done using the System.ComponentModel.IChangeTracking interface that is defined on entities and on entity graphs:

graph.AcceptChanges()

Disclaimer

var wheel = car.Wheels.First();
car.Wheels.Remove(wheel)