Is there a way to dynamically add EntitySets to an ODataConventionModelBuilder.
I'm working on an OData service in .net. Some of the entities we'll be returning are coming from an external assembly. I read the the assembly just fine and get the relevant types but since those types are variables I'm not sure how to define them as entity sets.
Example:
public static void Register(HttpConfiguration config)
{
//some config house keeping here
config.MapODataServiceRoute("odata", null, GetEdmModel(), new DefaultODataBatchHandler(GlobalConfiguration.DefaultServer));
//more config housekeeping
}
private static IEdmModel GetEdmModel()
{
ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
builder.Namespace = "SomeService";
builder.ContainerName = "DefaultContainer";
//These are the easy, available, in-house types
builder.EntitySet<Dog>("Dogs");
builder.EntitySet<Cat>("Cats");
builder.EntitySet<Horse>("Horses");
// Schema manager gets the rest of the relevant types from reading an assembly. I have them, now I just need to create entity sets for them
foreach (Type t in SchemaManager.GetEntityTypes)
{
builder.AddEntityType(t); //Great! but what if I want EntitySET ?
builder.Function(t.Name).Returns<IQueryable>(); //See if you can put correct IQueryable<Type> here.
//OR
builder.EntitySet<t>(t.Name); //exception due to using variable as type, even though variable IS a type
}
return builder.GetEdmModel();
}
Figured it out. Just add this line inside the loop:
builder.AddEntitySet(t.Name, builder.AddEntityType(t));
Related
I am using MapStruct to convert a Page object to a custom object of my application. I am using this mapping in order to convert the content field of the Page object to a list of custom objects found in my data model:
#Mapping(target = "journeys", source = "content")
While this works OK and does convert the elements when content is present, this does not work correctly in case of no Page content. Taking a look at the code seems to show that the following check is added in the generated mapper class:
if ( page.hasContent() ) {
List<JourneyDateViewResponseDto> list = page.getContent();
journeyDateViewPageResponseDto.setJourneys( new ArrayList<JourneyDateViewResponseDto>( list ) );
}
When this is added the mapping action of the inner objects is omitted, meaning that I end up with a null list. I am not really sure as to why and how this check is added but I would like to find a way of disabling it and simply end up with an empty list of elements. Is there a way this can be done using MapStruct?
MapStruct has the concept of presence checkers (methods that have the pattern hasXXX). This is used to decide if a source property needs to be mapped.
In case you want to have a default value in your object I would suggest making sure that your object is instantiated with an empty collection or provide an #ObjectFactory for your object in which you are going to set the empty collection.
e.g.
Default value in class
public class JourneyDateViewPageResponseDto {
protected List<JourneyDateViewResponseDto> journeys = new ArrayList<>();
//...
}
Using #ObjectFactory
#Mapper
public interface MyMapper {
JourneyDateViewPageResponseDto map(Page< JourneyDateViewResponseDto> page);
#ObjectFactory
default JourneyDateViewPageResponseDto createDto() {
JourneyDateViewPageResponseDto dto = new JourneyDateViewPageResponseDto();
dto.setJourneys(new ArrayList<>());
return dto;
}
}
#Mapping(target = "journeys", source = "content", defaultExpression = "java(java.util.List.of())")
I know how to retrieve a bean from a service in a datafetcher:
public class MyDataFetcher implements DataFetcher {
...
#Override
public Object get(DataFetchingEnvironment environment) {
return myService.getData();
}
}
But schemas with nested lists should use a BatchedExecutionStrategy and create batched DataFetchers with get() methods annotated #Batched (see graphql-java doc).
But where do I put my getData() call then?
///// Where to put this code?
List list = myService.getData();
/////
public class MyDataFetcher implements DataFetcher {
#Batched
public Object get(DataFetchingEnvironment environment) {
return list.get(environment.getIndex()); // where to get the index?
}
}
WARNING: The original BatchedExecutionStrategy has been deprecated and will get removed. The current preferred solution is the Data Loader library. Also, the entire execution engine is getting replaced in the future, and the new one will again support batching "natively". You can already use the new engine and the new BatchedExecutionStrategy (both in nextgen packages) but they have limited support for instrumentations. The answer below applies equally to both the legacy and the nextgen execution engine.
Look at it like this. Normal DataFetcherss receive a single object as source (DataFetchingEnvironment#getSource) and return a single object as a result. For example, if you had a query like:
{
user (name: "John") {
company {
revenue
}
}
Your company resolver (fetcher) would get a User object as source, and would be expected to somehow return a Company based on that e.g.
User owner = (User) environment.getSource();
Company company = companyService.findByOwner(owner);
return company;
Now, in the exact same scenario, if your DataFetcher was batched, and you used BatchedExecutionStrategy, instead of receiving a User and returning a Company, you'd receive a List<User> and would return a List<Company> instead.
E.g.
List<User> owners = (List<User>) environment.getSource();
List<Company> companies = companyService.findByOwners(owners);
return companies;
Notice that this means your underlying logic must have a way to fetch multiple things at once, otherwise it wouldn't be batched. So your myService.getData call would need to change, unless it can already fetch data for multiple source object in one go.
Also notice that batched resolution makes sense in nested queries only, as the top level resolver can already fetch a list of object, without the need for batching.
Inspired by this post dynamic-repositories-in-lightspeed I am trying to build my own like this.
I have a abstract GenericRepository like this. I have omitted most of the code for simplicity (Its just normal Add/Update/Filtering methods).
public abstract class GenericRepository<TEntity, TContext> :
DynamicObject,
IDataRepository<TEntity>
where TEntity : class, new()
where TContext : DbContext, new()
{
protected TContext context;
protected DbSet<TEntity> DbSet;
}
As you can see, my abstract GenericRepository extends from DynamicObject to support dynamic repositories.
I also have a abstract UnitOfWork implementation which generated a repository for a given entity at runtime like this. Again, base classes and other details are irrelevant for the question, but I'm happy to provide them if you require.
public abstract class UnitOfWorkBase<TContext> : IUnitOfWork
where TContext : DbContext, new()
{
public abstract IDataRepository<T> Repository<T>()
where T : class, IIdentifiableEntity, new();
// Code
}
Following class implements abstract method of the above class.
public class MyUnitOfWorkBase : UnitOfWorkBase<MyDataContext>
{
public override IDataRepository<T> Repository<T>()
{
if (Repositories == null)
Repositories = new Hashtable();
var type = typeof(T).Name;
if (!Repositories.ContainsKey(type))
{
var repositoryType = typeof(GenericRepositoryImpl<,>);
var genericType = repositoryType.MakeGenericType(typeof(T), typeof(InTeleBillContext));
var repositoryInstance = Activator.CreateInstance(genericType);
Repositories.Add(type, repositoryInstance);
}
return (IDataRepository<T>)Repositories[type];
}
}
Now, whenever I want to create a dynamic repository for basic CRUD functions, I can do it like this.
var uow = new MyUnitOfWorkBase();
var settingsRepo = uow.Repository<Settings>();
var settingsList = settingsRepo.Get().ToList();
Now, What I want to do is something like this.
dynamic settingsRepo = uow.Repository<Settings>();
var result = settingsRepo.FindSettingsByCustomerNumber(774278L);
Here, FindSettingsByCustomerNumber() is a dynamic method. I resolve this method using this code.
public class GenericRepositoryImpl<TEntity, TContext> :
GenericRepository<TEntity, TContext>
where TEntity : class, IIdentifiableEntity, new()
where TContext : DbContext, new()
{
public override bool TryInvokeMember(InvokeMemberBinder binder,
object[] args, out object result)
{
// Crude parsing for simplicity
if (binder.Name.StartsWith("Find"))
{
int byIndex = binder.Name.IndexOf("By");
if (byIndex >= 0)
{
string collectionName = binder.Name.Substring(4, byIndex - 4);
string[] attributes = binder.Name.Substring(byIndex + 2)
.Split(new[] { "And" }, StringSplitOptions.None);
var items = DbSet.ToList();
Func<TEntity, bool> predicate = entity => entity.GetType().GetProperty(attributes[0]).GetValue(entity).Equals(args[0]);
result = items.Where(predicate).ToList();
return true;
}
}
return base.TryInvokeMember(binder, args, out result);
}
}
This is the problem I am having.
using this line var items = DbSet.ToList(); works well, but if I were to query a large table with 1000's of data, then performance issues occur.
If I directly try to use the IQueryble interface and call it like this
Func predicate = entity => entity.GetType().GetProperty(attributes[0]).GetValue(entity).Equals(args[0]);
result = DbSet.Where(predicate).ToList();
It gives me an error saying there is no method GetProperty() in LINQ to Entities.
Is it possible to make it work using LINQ to Entities?
You need to know that LINQ-to-Entities needs to convert your expression (given by the predicate) into a SQL query. entity is replaced by the database column. Additionally LINQ2Entities supports various expressions (e.g. EqualExpression, etc.). However it cannot support the whole .NET Framework. Especially: what should GetType() on a database column return?
Therefore you need to use the Expresson API to generate the predicate and use only expressions supported by LINQ2Entities. For example: Use a MemberAccess expression for accessing a property (LINQ2Entities is able to map that to an SQL query).
Hint: we are doing predicate generation for Entity Framework and had to overcome some additional problems which we could solve using the library LinqKit.
If you do not know about the .NET Expression API yet, you need to gather skills in that area before you can resume your dynamic repository idea.
BTW: I don't think that it is a very good idea to have this kind of automatic calls. They are not refactoring safe (i.e. what if you rename the DB column? All your method calls run into problems, and it is not detectable by the compiler).
I would use it only to generate predicates for Where() clauses from Filter-like DTO types.
Unusual pattern - dynamic methods on a repository patterns.But that is another topic.
Dynamic invocation of the repository you have.
So now you need to understand Linq to Entities a little more.
Linq to Entities language reference what you can do with linq to Entities.
Given the expression tree has to be converted in to DB instructions,
it isnt surprising there are restrictions.
In case you are interested The EF provider specs and links to samples
So given you want to Dynamic EF, you have a few options.
I concentrate on dynamic wheres, but you can apply to other EF methods.
Check out
Dynamic Linq on codeplex
which allows things like
public virtual IQueryable<TPoco> DynamicWhere(string predicate, params object[] values) {
return Context.Set<TPoco>().Where(predicate, values);
}
This Where is an IQueryable extension that accepts strings...
Samples of using this string based predicate parser
LinqKit or even PM> Install-Package LinqKit
Linqkit takes dynamic EF to the next level,
Offers amazing features like
public IQueryable<TPoco> AsExpandable() {
return Context.Set<TPoco>().AsExpandable();
}
which allows you build AND and ORs progressively.
Expression trees
Expression Building API is the most powerful tool to support you here .
Learning the API is hard. using the tool harder.
eg Dealing with concatenation very hard. BUT if you can understand the API and how expressions work.
It is possible.
Here is a SIMPLE example. (imagine something complex)
public static Expression<Func<TPoco, bool>> GetContainsPredicate<TPoco>(string propertyName,
string containsValue)
{
// (tpoco t) => t.propertyName.Contains(value ) is built
var parameterExp = Expression.Parameter(typeof(TPoco), #"t");
var propertyExp = Expression.Property(parameterExp, propertyName);
MethodInfo method = typeof(string).GetMethod(#"Contains", new[] { typeof(string) });
var someValue = Expression.Constant(containsValue, typeof(string));
var containsMethodExp = Expression.Call(propertyExp, method, someValue);
return Expression.Lambda<Func<TPoco, bool>>(containsMethodExp, parameterExp);
}
I'm trying to bring test layer to my project but I'm not getting there :( hope someone can help me.
Controller (based on Automapper mapping and Dependency Injection Container):
public virtual ActionResult SearchCategories(string keywords)
{
var result = _categoryService.SearchCategories(keywords);
var resultViewModel = Mapper.
Map<IList<SearchCategoriesDto>,
IList<SearchCategoriesViewModel>>(result);
return View(resultViewModel);
}
Service Layer:
public IList<SearchCategoriesDto> SearchCategories(String keywords)
{
// Find the keywords in the Keywords table
var keywordQuery = _keywordRepository.Query;
foreach (string keyword in splitKeywords)
{
keywordQuery = keywordQuery.Where(p => p.Name == keyword);
}
// Get the Categories from the Search
var keywordAdCategoryQuery = _keywordAdCategoryRepository.Query;
var categoryQuery = _categoryRepository.Query;
var query = from k in keywordQuery
join kac in keywordAdCategoryQuery on k.Id equals kac.Keyword_Id
join c in categoryQuery on kac.Category_Id equals c.Id
select new SearchCategoriesDto
{
Id = c.Id,
Name = c.Name,
SearchCount = keywordAdCategoryQuery
.Where(s => s.Category_Id == c.Id)
.GroupBy(p => p.Ad_Id).Count(),
ListController = c.ListController,
ListAction = c.ListAction
};
var searchResults = query.Distinct().ToList();
return searchResults;
}
Test maded but not working:
[TestMethod]
public void Home_SearchCategories_Test()
{
// Setup
var catetoryService = new CategoryService(
_categoryRepository,
_keywordRepository,
_keywordAdCategoryRepository);
// Act
var result = catetoryService.SearchCategories("audi");
// Add verifications here
Assert.IsTrue(result.Count > 0);
}
Thanks.
I am assuming you want to create an integration test for your category service, using real repositories and database. (as oposed to an unit test where you would use stub\mocks for those repositories and test the service class in isolation)
So you would have a seaparated test assembly where you will add your integration tests, for example having a class for the integration tests at the service level.
On that class you will then create instances of all the repositories and the CategoryService before running each test, on a method with the attribute [TestInitialize]. (A method with this attribute will be run by msTest before each test)
As you are also truly working with the database you would like to be sure that any resources used are disposed. For example, disposing an entity framework context. In that case you would add a method with an attribute [TestCleanup] where you will perform any cleanup logic needed. (A method with this attribute will be run by msTest after each test)
With those methods you will make sure you have a fresh service and repositories instances on each test. Then you will implement each individual integration test following the AAA pattern (Arrange, Act, Assert)
So an example of your integration test class with that single test may look like:
public class CategoryServiceIntegrationTest
{
//dependencies of your class under test
private ICategoryRepository _categoryRepository;
private IKeywordRepository _keywordRepository;
private IKeywordAdCategoryRepository _keywordAdCategoryRepository;
//your class under test
private CategoryService _categoryService;
[TestInitialize]
public void InitializeBeforeRunningATest()
{
//manually create instances of the classes implementing the repositories
//I don´t know about how they are implemented but I guess
//you would need to provide the name of a connection string in the config file (in that case this should be in a config file of the test project)
//,the connection string itself
//or maybe you need to initialize an entity framework context
_categoryRepository = new CategoryRepository( /*whatever you need to provide*/);
_keywordRepository = new KeywordRepository( /*whatever you need to provide*/);
_keywordAdCategoryRepository = new KeywordAdCategoryRepository( /*whatever you need to provide*/);
//Create the class under test with all repositories dependencies
//as it is an integration test, they are your real objects and not mocks\stubs
_categoryService = new CategoryService(_categoryRepository,
_keywordRepository,
_keywordAdCategoryRepository);
}
[TestCleanup]
public void CleanDatabaseResources()
{
//just in case you need to do something like disposing an EF context object
}
[TestMethod]
public void Home_SearchCategories_Test()
{
// Arrange
var keywords = "audi";
// Act (the _categoryService instance was created in the initialize method)
var result = _categoryService.SearchCategories(keywords);
// Assert
Assert.IsTrue(result.Count > 0);
}
}
Solution to build an Integration test for a Service (in this case, Category Service), using Autofac, Automapper (not necessary in this Service but if it would be necessary, you would need to put in the TestInitialize method as you can see in the coment line in the following solution) and Entity Framework with Daniel J.G. help (thanks Daniel):
First of all I created a separated Test Project using MSTest (only because there is a lot of documentation about it).
Second you need to put the connection string for the Entity Framework where the test data is:
<connectionStrings>
<add name="DB" connectionString="Data Source=.\sqlexpress;Database=DBNAME;UID=DBUSER;pwd=DBPASSWORD;MultipleActiveResultSets=True;" providerName="System.Data.SqlClient" />
</connectionStrings>
In the < configuration > section after the < / configSections >
Third you create the class for the test:
namespace Heelp.Tests
{
[TestClass]
public class CategoryServiceIntegrationTest
{
// Respositories dependencies
private IRepository<Category> _categoryRepository;
private IRepository<Keyword> _keywordRepository;
private IRepository<KeywordAdCategory> _keywordAdCategoryRepository;
// Service under test: Category Service
private CategoryService _categoryService;
// Context under test: HeelpDB Connection String in app.config
private HeelpDbContext db;
[TestInitialize]
public void InitializeBeforeRunningATest()
{
// IoC dependencies registrations
AutofacConfig.RegisterDependencies();
// HERE YOU CAN CALL THE AUTOMAPPER CONFIGURE METHOD
// IN MY PROJECT I USE AutoMapperConfiguration.Configure();
// IT'S LOCATED IN THE App_Start FOLDER IN THE AutoMapperConfig.cs CLASS
// CALLED FROM GLOBAL.ASAX Application_Start() METHOD
// Database context initialization
db = new HeelpDbContext();
// Repositories initialization
_categoryRepository = new Repository<Category>(db);
_keywordRepository = new Repository<Keyword>(db);
_keywordAdCategoryRepository = new Repository<KeywordAdCategory>(db);
// Service initialization
_categoryService = new CategoryService(_categoryRepository,
_keywordRepository,
_keywordAdCategoryRepository);
}
[TestCleanup]
public void CleanDatabaseResources()
{
// Release the Entity Framework Context for other tests that will create a fresh new context.
// With this method, we will make sure that we have a fresh service and repositories instances on each test.
db.Dispose();
}
[TestMethod]
public void Home_SearchCategories_Test()
{
// Arrange
var keywords = "audi";
// Act (the _categoryService instance was created in the initialize method)
var result = _categoryService.SearchCategories(keywords);
// Assert
Assert.IsTrue(result.Count > 0);
}
}
}
Now you just have to run the test to see if it passes.
To garantee integration tests, I would recomend a second database identical from the original/production database in terms of tables, but with only your test data.
This will ensure that the tests results will remain the same based on your test data.
The only drawback is that you will need to keep sincronized the tables, but you can use SQL Admin Studio Freeware Tool from Simego to achieve that.
Regards.
I have two tables in my database connected by foreign keys: Page (PageId, other data) and PageTag (PageId, Tag). I've used LINQ to generate classes for these tables, with the page as the parent and the Tag as the child collection (one to many relationship). Is there any way to mark PageTag records for deletion from the database from within the Page class?
Quick Clearification:
I want the child objects to be deleted when the parent DataContext calls SubmitChanges(), not before. I want TagString to behave exactly like any of the other properties of the Page object.
I would like to enable code like the following:
Page page = mDataContext.Pages.Where(page => page.pageId = 1);
page.TagString = "new set of tags";
//Changes have not been written to the database at this point.
mDataContext.SubmitChanges();
//All changes should now be saved to the database.
Here is my situation in detail:
In order to make working with the collection of tags easier, I've added a property to the Page object that treats the Tag collection as a string:
public string TagString {
get {
StringBuilder output = new StringBuilder();
foreach (PageTag tag in PageTags) {
output.Append(tag.Tag + " ");
}
if (output.Length > 0) {
output.Remove(output.Length - 1, 1);
}
return output.ToString();
}
set {
string[] tags = value.Split(' ');
PageTags.Clear();
foreach (string tag in tags) {
PageTag pageTag = new PageTag();
pageTag.Tag = tag;
PageTags.Add(pageTag);
}
}
}
Basically, the idea is that when a string of tags is sent to this property, the current tags of the object are deleted and a new set is generated in their place.
The problem I'm encountering is that this line:
PageTags.Clear();
Doesn't actually delete the old tags from the database when changes are submitted.
Looking around, the "proper" way to delete things seems to be to call the DeleteOnSubmit method of the data context class. But I don't appear to have access to the DataContext class from within the Page class.
Does anyone know of a way to mark the child elements for deletion from the database from within the Page class?
After some more research, I believe I've managed to find a solution. Marking an object for deletion when it's removed from a collection is controlled by the DeleteOnNull parameter of the Association attribute.
This parameter is set to true when the relationship between two tables is marked with OnDelete Cascade.
Unfortunately, there is no way to set this attribute from within the designer, and no way to set it from within the partial class in the *DataContext.cs file. The only way to set it without enabling cascading deletes is to manually edit the *DataContext.designer.cs file.
In my case, this meant finding the Page association, and adding the DeleteOnNull property:
[Association(Name="Page_PageTag", Storage="_Page", ThisKey="PageId", OtherKey="iPageId", IsForeignKey=true)]
public Page Page
{
...
}
And adding the DeleteOnNull attribute:
[Association(Name="Page_PageTag", Storage="_Page", ThisKey="PageId", OtherKey="iPageId", IsForeignKey=true, DeleteOnNull = true)]
public Page Page
{
...
}
Note that the attribute needed to be added to the Page property of the PageTag class, not the other way around.
See also:
Beth Massi -- LINQ to SQL and One-To-Many Relationships
Dave Brace -- LINQ to SQL: DeleteOnNull
Sorry, my bad. That won't work.
It really looks like you need to be doing this in your repository, rather than in your Page class. There, you have access to your original data context.
There is a way to "attach" the original data context, but by the time you do that, it has become quite the code smell.
Do you have a relationship, in your Linq to SQL entity diagram, linking the Page and PageTags tables? If you don't, that is why you can't see the PageTags class from the Page class.
If the foreign key in the PageTags database table is set to Allow Nulls, Linq to SQL will not create the link when you drag the tables into the designer, even if you created a relationship on the SQL Server.
This is one of those areas where OR mapping can get kind of hairy. Providing this TagString property makes things a bit more convenient, but in the long run it obfuscates what is really happening when someone utilizes the TagString property. By hiding the fact that your performing data modification, someone can very easily come along and set the TagString without using your Page entity within the scope of a DataContext, which could lead to some difficult to find bugs.
A better solution would be to add a Tags property on the Page class with the L2S model designer, and require that the PageTags be edited directly on the Tags property, within the scope of a DataContext. Make the TagString property read only, so it can be genreated (and still provide some convenience), but eliminate the confusion and difficulty around setting that property. This kind of change clarifies intent, and makes it obvious what is happening and what is required by consumers of the Page object to make it happen.
Since Tags is a property of your Page object, as long as it is attached to a DataContext, any changes to that collection will properly trigger deletions or insertions in the database in response to Remove or Add calls.
Aaron,
Apparently you have to loop thru your PageTag records, calling DeleteOnSubmit for each one. Linq to SQL should create an aggregate query to delete all of the records at once when you call SubmitChanges, so overhead should be minimal.
replace
PageTags.Clear();
with
foreach (PageTag tag in PageTags)
myDataContext.DeleteOnSubmit(tag);
Aaron:
Add a DataContext member to your PageTag partial class.
partial class PageTag
{
DataClassesDataContext myDataContext = new DataClassesDataContext();
public string TagString {
..etc.
Larger code sample posted at Robert Harvey's request:
DataContext.cs file:
namespace MyProject.Library.Model
{
using Tome.Library.Parsing;
using System.Text;
partial class Page
{
//Part of Robert Harvey's proposed solution.
MyDataContext mDataContext = new TomeDataContext();
public string TagString {
get {
StringBuilder output = new StringBuilder();
foreach (PageTag tag in PageTags) {
output.Append(tag.Tag + " ");
}
if (output.Length > 0) {
output.Remove(output.Length - 1, 1);
}
return output.ToString();
}
set {
string[] tags = value.Split(' ');
//Original code, fails to mark for deletion.
//PageTags.Clear();
//Robert Harvey's suggestion, thorws exception "Cannot remove an entity that has not been attached."
foreach (PageTag tag in PageTags) {
mDataContext.PageTags.DeleteOnSubmit(tag);
}
foreach (string tag in tags) {
PageTag PageTag = new PageTag();
PageTag.Tag = tag;
PageTags.Add(PageTag);
}
}
}
private bool mIsNew;
public bool IsNew {
get {
return mIsNew;
}
}
partial void OnCreated() {
mIsNew = true;
}
partial void OnLoaded() {
mIsNew = false;
}
}
}
Repository Methods:
public void Save() {
mDataContext.SubmitChanges();
}
public Page GetPage(string pageName) {
Page page =
(from p in mDataContext.Pages
where p.FileName == pageName
select p).SingleOrDefault();
return page;
}
Usage:
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Edit(string pageName, FormCollection formValues) {
Page updatedPage = mRepository.GetPage(pageName);
//TagString is a Form value, and is set via UpdateModel.
UpdateModel(updatedPage, formValues.ToValueProvider());
updatedPage.FileName = pageName;
//At this point NO changes should have been written to the database.
mRepository.Save();
//All changes should NOW be saved to the database.
return RedirectToAction("Index", "Pages", new { PageName = pageName });
}