Orchard data entry forms without admin - asp.net-mvc

We're working diligently at learning Orchard, with a goal of creating not websites, but business-centric web applications that we would normally write in months using MVC, but hope to be much more efficient by using the various Parts already available.
The last mile, though, seems to be a big block -- how to tell Orchard that it should create a shape that allows the end-user to edit some data? There's a good bit on most of end-user editing at Creating a module for Orchard that stores data from the front-end but it picks up after the data's already been entered and carries it through the controller's POST operation. What I can't figure out is how to get through the initial GET operation.
To elaborate, in straight MVC I might allow the user to enter information about themselves. So I'd have /Controllers/PersonController.cs and there write a Create() function. I'd add a View in /Views/Person/Create.cshtml and simply "return View()" from the controller. In Create(Person p), an HTTPGet method, I'd do the heavy lifting to save the object.
Now in Orchard I have my PersonPart and its PersonPartDriver which, as I understand from the above article, I would write my POST method to accept the PersonPart and save the object.
class PersonController : Controller
{
private readonly IRepository<PersonPartRecord> personRepository;
public PersonController(IRepository<PersonPartRecord> _personRepository) {
personRepository = _personRepository;
}
[HttpPost]
public Create(PersonPart part) {
personRepository.Create(part.Record);
}
}
All well, but how would I get Orchard to invoke the GET Editor(PersonPart, dynamic) method to get the form up for the user to do the initial data entry?
protected override DriverResult Editor(PersonPart part, dynamic shapeHelper)
{
return ContentShape("Parts_Person_Edit",
() => shapeHelper.EditorTemplate(
TemplateName: "Parts/Person",
Model: part,
Prefix: Prefix));
}
Or do I write the GET Create() method in the controller? If I do that, though, I'm bypassing the entire shape creation system, no? Something itches in the back of my brain saying I should rather be doing a Display() and, in the template, just making it an editable form, but I have a Display() for the readonly view of Person ... how to make it know I want the editable view?
Hope the question makes sense, and hope that someone can assist.
Thanks.

Have a look to Orchard.CustomForms
var model = _contentManager.BuildEditor(contentItem);
return View(model);
but you'll need something like the code above. You could return ShapeResult(this,model) too

Related

.NET MVC preventing forged POST

SITUATION:
I have a Model and based on a users Role I want to allow the user to only update certain parts of the model. Lets say the Model has three fields. (My Model is obviously more complex than this)
MyObject
Field1
Field2
Field3
My View looks something like this:
Html.TextBoxFor(#Model.Field1)
Html.TextBoxFor(#Model.Field2)
#if(UserIsAdmin())
Html.TextBoxFor(#Model.Field3)
else
#Model.Field3
Bearing with me on the syntax (and the poor design of the example), you can see what I'm trying to do. Upon the user posting the form my controller would just take the MyObject and save it back to the database, we are using EF.
QUESTION:
My question is, is there a way to stop a user from forging a POST to be able to save data he/she should not be able to. My current idea would be to do a check in the controller to see if the user modified values he should not have. Or I could save fields individually, but neither is a convient solution.
Is there a better one?
Thanks!
Additional Info:
Not sure if this artical is relevant at all: http://blog.stevensanderson.com/2008/09/01/prevent-cross-site-request-forgery-csrf-using-aspnet-mvcs-antiforgerytoken-helper/
All three fields are from the same database table and I'm using EF to get and save the entity.
You want to make sure the user is only able to update permitted fields.
You decided that the way to achieve this is to prevent the user "forging" a response using e.g. firebug, or F12 developer tools, or GreaseMonkey, and have asked how to do this.
But the correct/best method is to check which fields the user is attempting to update, and only update those which he is permitted to update. Then it doesn't matter if they forge the request or not, they still won't be able to access anything they shouldn't. In other words, check access rights at the point of access.
Anti-forgery tokens are there to solve a separate problem, namely XSRF.
Use a viewmodel that accepts only the fields that should be updated and then populate the model with those values. You could use something like AutoMapper for mapping between the two.
My current idea would be to do a check in the controller to see if the user modified values he should not have. Or I could save fields individually, but neither is a convient solution.
You're on the right track with that idea. A typical Add() operation would look like this:
public class FooController : Controller
{
public ActionResult Add(FooViewModel viewModel)
{
if (ModelState.IsValid)
{
FooDataModel dataModel = FooMapper.MapToDataModel(viewModel, User);
FooRepository.Add(dataModel);
}
}
}
Like #VimalStan said, your FooViewModel is then a model that contains only the fields you want to let the user update. Also this still doesn't solve your problem, which should be done in your mapper (in this case FooMapper) and still check every field as #Ben suggested:
public static class FooMapper
{
public static FooDataModel Map(FooViewModel viewModel, IPrincipal user)
{
var dataModel = new FooDataModel();
dataModel.Field1 = viewModel.Field1;
dataModel.Field2 = viewModel.Field2;
if (IsAllowedToUpdateField3(user))
{
dataModel.Field3 = viewModel.Field3;
}
return dataModel;
}
public static bool IsAllowedToUpdateField3(IPrincipal user)
{
return false; // your logic
}
}

EF Reference gets lost when Web API returns IQueryable

I have been looking for quite some time now on this problem.
Here's the deal.
I'm building a website that calls to a Web API to get its data. My Web API uses a library, working with repository pattern. My database model (EF Model-first) was build in the library. In that model I have a base class Pass. Then I have two derived classes, CustomerCard : Pass and Voucher : Pass. My model from EF Designer
I have a method to get all the CustomerCards.
public IQueryable<CustomerCard> GetAllPasses() {
IList<CustomerCard> allCards = new List<CustomerCard>();
var c_cards = context.Passes;
foreach (var c_card in c_cards) {
if (c_card is CustomerCard) {
allCards.Add((CustomerCard)c_card);
}
}
return allCards.AsQueryable<CustomerCard>();
}
In my ApiController, I use this method to get the passes and return them to the website, like this:
[HttpGet]
[Queryable]
public IQueryable<CustomerCard> GetAllPasses(string version) {
return passRepo.GetAllPasses().AsQueryable();
}
My Web API returns JSON format. This is my config to preserve referencing and stuff:
var json = config.Formatters.JsonFormatter;
json.SerializerSettings.PreserveReferencesHandling =
Newtonsoft.Json.PreserveReferencesHandling.Objects;
json.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Serialize;
config.Formatters.Remove(config.Formatters.XmlFormatter);
I'm using IQueryable because I want to be able to page the data on my website. The api method is available at '/api/v1/passes/all'.
Here's the strange part. To test my paging, I call 1 pass per page.
For my first Pass, it works fine. But when I go to my second page, he also gets the correct pass, but the reference to User is gone.
As you can see in my model, the CustomerCard class has a property User. This indicates who owns the customer card.
So this call loads the user from the pass: 'api/v1/passes/all?$top=1'
but when I call to this one, the user instance is NULL: 'api/v1/passes/all?$top=1&$skip=1'.
However, when I call to 'api/v1/passes/all?$top=2', the User for the second pass IS loaded.
So this is where my mind get's blown! I don't get it? Why doesn't the user-reference comes along with the second one? Could it have something to do with the Lazy loading feature of the EF?
EDIT
When I use the extension method Include on context.passes, an error is thrown:
A specified Include path is not valid. The EntityType 'LCS_Model.Pass'
does not declare a navigation property with the name 'User'.
This is because Passes as a dbset, contains CustomerCard as well as Voucher. Is there a way I can tell my context to expect or convert it to a CustomerCard?
Can someone please help me. If you don't understand my question, ask away!
Thanks allready!
EDIT 2
The method on my API controller is now
[HttpGet]
[Queryable]
public IQueryable<CustomerCard> GetAllPasses(string version) {
return context.Passes.Include("User").OfType<CustomerCard>();
}
This gives me my correct items. I have 2 customer cards in my db. Both are from the same user. My API has the user still loaded. The moment my website receives the response, the User property becomes null. My guess is that it's because it is still referencing to the same user from the first element of the array. Is that possible? And if yes, how can I prevent that from happening?
Yes, you need to make sure any related records are included when you do your query. See this for some examples. Secondly... I fail to understand why you are doing all that work with the for loop... That's a lot of absolutely needless and wasted work for the server to do if you want to do any paging. I'm thinking, besides any other filters you might want to apply, your GetAllPasses should look something like this.
public IQueryable<CustomerCard> GetAllPasses() {
return context.Passes.Include(r => r.User);
}
Edit (2): I need to read better. I have to confess, I'm not familiar with type inheritance in EF. I found some things that might work here: table per hierarchy, table per concrete type, and see also also MSDN Queryable.OfType<TResult>. This is a guess, but let's try:
public IQueryable<CustomerCard> GetAllPasses() {
return context.Passes.OfType<CustomerCard>().Include(r => r.User);
}

How can I create a binding in Ninject that changes based on the requested controller?

I have an ASP.NET MVC 3 app, and have run into the following situation. On my page, I have a side bar, which can contain related links specific to that page, i.e., determined by controller type. The links will be determined by the current page's content.
I have followed Phil Haack's blog post on rendering dynamic side bars such as this using Html.Action and a separate controller. I like the separation of concerns this approach gives me: my controllers don't know anything about the side bar at all, which is the way it should be.
I now want to inject an instance of a derived type of SideBar into my SideBarController, an action on which will be called to render the side bar itself. There is one derived type of SideBar per controller, and so I find myself wanting to write code similar to this:
kernel.Bind<SideBar>().ToMethod(_ => controllerName == "foo"
? new FooSideBar(kernel.Get<UrlHelper>())
: new BarSideBar(kernel.Get<UrlHelper>()));
but there's quite a lot that is wrong about that fragment of code, not least the fact that I can't get hold of the controller name in the lambda, and the question of what happens when a third type of controller comes along, and then a fourth, etc.
Note that I can't use WhenInjectedInto<T>(), as the SideBar instance will always be injected into the SideBarController.
For what it's worth, the instances of SideBar are currently being created via the Ninject Factory extension, so the relevant side bar bindings are as follows (I've hard-bound an implementation of SideBar just to prove the approach so far works):
kernel.Bind<ISideBarFactory>().ToFactory().InRequestScope();
kernel.Bind<SideBar>().To<FooSideBar>().InRequestScope();
Finally, I essentially have a one-to-one mapping between the derived types of SideBar and the controller types. It feels a little bit like there might be a bit of duplication here, but also it represents the relationship between the components, so I think I'm ok with it.
This all makes me think that my approach to this part of the problem is wrong, and so I would welcome suggestions on how to achieve a clean solution with Ninject.
I'll have a go at answering, but I'm not near a computer at the moment, and so it'll be a bit vague.
Fundamentally, you can pass another parameter to Html.Action, so if that parameter is either the Request or something gleaned from the Request (such as the controller name or Url parts) then you can use that to determine which sidebar to show. You may need to inject the factory into the sidebar controller, and use it to create the correct controller, or some other fiddling about, but once you know which sidebar is required, it becomes much easier.
I am not sure if this is possible using ninject but it is using ModelBinding like so:
public interface ISidebar
{
}
public class Sidebar1 : ISidebar
{
}
public class Sidebar2 : ISidebar
{
}
public class SidebarModelBinder : IModelBinder
{
public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
var controller = controllerContext.RouteData.Values["Controller"];
var action = controllerContext.RouteData.Values["Action"];
switch (controller.ToString())
{
case "Home":
return new Sidebar1();
default:
return new Sidebar2();
}
throw new NotImplementedException();
}
}
public class TestController : Controller
{
public TestController()
{
}
public string Index(ISidebar sidebar)
{
//Do something with it
return "OK";
}
}
//Add to the Application_Start
ModelBinders.Binders.Add(typeof(ISidebar), new SidebarModelBinder());
EDIT: Took me a while, but managed to get it working using Ninject.
Please read it at: http://blog.voltje.be/2012/08/22/creating-a-dynamic-sidebar-with-asp-net-mvc-ninject/
Suggestion:
Don't inject sidebar.
Instead inject [sidebar]ContentProvider.
Bind a default implementation in global asax (per request), then unbind and rebind if needed in the controller.

TryUpdateModel not working as expected

I'm working on an ASP.NET MVC project that will allow users to perform batch edits on the attributes of objects. The implementation is in a sort of "wizard" like form with four phases to the process as follows:
"Select the attributes you want to edit" - the first page will present the user with a list of checkboxes representing each of the attributes they want to edit. The user should check the attributes they wish to edit and select "Continue".
"Edit the selected attributes" - the second page will present the user with a list of distinct "editors" which will be unique for each of the attributes they selected on the first page.
"Review your changes" - this page will allow the user to review the changes they've made to the attributes they selected.
"Submit your changes" - this page will actually submit the information about the edits the user wishes to make to the selected attributes against the selected collection of objects.
Fairly straight-forward.
As I mentioned, the "editor" will be unique to each attribute, and could have any combination of different controls on it. Once a user has made their edits and the application posts that information to the "Review" page is where I'm currently having my problem.
We've developed the concept of an "EditorWorker" class that is unique to each attribute, which is responsible for generating the ViewModel necessary for each editor, but is also responsible for creating/returning (within the "Review" page controller action) an object that is the "model" object for the editor that the post data can be bound to, which can then be use to display the edited data for review. This object should have properties that match up with the IDs of the controls in the editor so that model binding can occur.
I've got the "EditorWorker" creating and returning the class needed, but for some reason, when I call TryUpdateModel and pass in that class, its properties aren't getting populated as a result of that method call as I would expect them to. I have verified that the values are in the posted FormCollection. Below is the code for my controller action where I'm attempting to do this. If someone can help me understand why TryUpdateModel isn't working in this scenario, I would be very appreciative.
[HttpPost]
public virtual ActionResult Review(ReviewBatchViewModel model)
{
var selectedAttributes = GetSelectedAttributes(model.SelectedAttributeIds.Split(',').Select(i => Int64.Parse(i)).ToArray());
var workers = new List<IEditorWorker>();
var reviewData = new Dictionary<ViewAttribute, IEditData>();
foreach (var attribute in selectedAttributes)
{
if (!string.IsNullOrEmpty(attribute.EditorWorker)) // If there is no EditorWorker defined for this object, move on...
{
var worker = ServiceLocator.Current.GetInstance(Type.GetType(string.Format("{0}.{1}", EditorWorkerNamespace, attribute.EditorWorker)));
var attributeEditData = ((IEditorWorker)worker).LoadEditData();
if (TryUpdateModel(attributeEditData))
model.EditData.Add(attributeEditData); // model.EditData is a List<IEditData> that will be iterated on the Review page
reviewData.Add(attribute, attributeEditData);
}
}
return View(model);
}
// ReviewBatchViewModel.cs
public class ReviewBatchViewModel : BaseViewModel
{
public ReviewBatchViewModel() { EditData = new List<IEditData>(); }
public string SelectedAttributeIds { get; set; }
public List<ViewAttribute> SelectedAttributes { get; set; }
public List<IEditData> EditData { get; set; }
}
// IEditData.cs
public interface IEditData
{
}
// BroadcastStatusEditData.cs
public class BroadcastStatusEditData : IEditData
{
public int BroadcastStatus { get; set; }
}
I totally understand that this controller action is incomplete in its current state. I'm presently working on just trying to get those EditData objects populated correctly before I move on. As mentioned, any thoughts would be greatly appreciated. Thanks.
UPDATE: With regards to #mare's comment, I should have explained that part more clearly, sorry. The call to TryUpdateModel actually is returning true, but the fields on the model object being passed into it aren't actually being populated from the values that have been confirmed present in the posted form data. The model object being passed into the call is not a List, its just a poco. The resulting, ultimately hopefully populated model object is then being added to a List collection of model objects that will then be used for displaying the posted data for review on the Review page. I'm not loading anything from a datastore at all. Unique editors for each selected attribute are being rendered to the Edit screen, and I'm attempting to capture the edit values for display on a Review screen prior to submitting the batch of edits to a service. Hopefully that's more clear. Thanks.
UPDATE 2: I've included the definition of the ReviewBatchViewModel class as requested by #mare in the comments. The use of the var keyword in most cases in this code sample is largely due to the fact that the methods that are populating those variables is going to be returning an object of a different type for each attribute selected, so I never know exactly what its going to be at runtime (although it will always implement an interface, in this case either IEditorWorker and/or IEditData). There is a single class in the Model called "Attribute". The provided code sample has three variables relative that class: 1) SelectedAttributeIds is a comma-separated list of the Id's of the attributes that the user has selected to edit, which gets passed from the Edit page to the Review page via hidden field, 2) selectedAttributes is a collection of the actual Attribute objects that correspond to those Ids that I can work with, and 3) attributeEditData is an instance of the IEditData class specific to each given attribute that I'm attempting to bind the posted data from the Edit page to.
Hopefully this additional information clears things up even more.
TryUpdateModel is a generic method, and therefore attempts to infer all type information based on the Generic Type Parameter.
From what I understand in your example above, you are always passing in a IEditData correct?
In effect you are saying:
TryUpdateModel<IEditData>(attributeEditData)
This is most likely the cause for not seeing any properties being set, since IEditData doesn't have any properties ;)
To do what you want you will probably have to create a custom ModelBinder.
As a quick code review side note, your solution seems overly complicated. I had to stare at your solution for a good while just to figure out where to start. Creating a custom model binder may solve your immediate problem, but you might be looking at a big time maintenance headache here. I'm willing to bet there is a simpler approach that will lead to fewer problems down the road.
Based on your comments I have changed the code around from System.Object to your IEditData interface, but everything still holds. I noticed in an earlier comment you mentioned using var because you didn't know the type until runtime. However, there is nothing magic about the var keyword. The only thing it does is give you implicit typing, but it is still statically typed.
The nice thing about MVC is that you can just pop over to Codeplex and have a look at the source for TryUpdateModel if you want. Digging down a few layers you will eventually find a call to this internal method:
protected internal bool TryUpdateModel<TModel>(TModel model, string prefix, string[] includeProperties, string[] excludeProperties, IDictionary<string, ValueProviderResult> valueProvider) where TModel : class {
if (model == null) {
throw new ArgumentNullException("model");
}
//valueProvider is passed into this internal method by
// referencing the public ControlerBase.ValueProvider property
if (valueProvider == null) {
throw new ArgumentNullException("valueProvider");
}
Predicate<string> propertyFilter = propertyName => BindAttribute.IsPropertyAllowed(propertyName, includeProperties, excludeProperties);
//Binders is an internal property that can be replaced by
// referencing the static class ModelBinders.Binders
IModelBinder binder = Binders.GetBinder(typeof(TModel));
ModelBindingContext bindingContext = new ModelBindingContext() {
Model = model,
ModelName = prefix,
ModelState = ModelState,
ModelType = typeof(TModel),
PropertyFilter = propertyFilter,
ValueProvider = valueProvider
};
binder.BindModel(ControllerContext, bindingContext);
return ModelState.IsValid;
}
Notice the use of typeof(TModel) everywhere... in your case that is getting translated into typeof(IEditData), which isn't very useful since it is only a marker interface. You should be able to adapt this code for your own use, making sure to use GetType() in order to get the actual type at runtime.
I hope this helps out!
P.S. I've added some comments to the above code to help out a little
#Josh, you were very helpful in helping me understand why TryUpdateModel wasn't working for me, and I appreciate that. Unfortunately, I think the larger issue here was that fact that I (not exactly sure which) was either unable or unwilling to try to document all of the details of the requirements for the problem I'm trying to solve here, which I think made it difficult for anyone to be able to provide much meaningful input. The biggest problem for us is that, because we have no idea until runtime which attributes a user has selected for editing, we don't know which objects we'll be working with in the context of these controller actions, or what their types will be. The one place that we safely can work with known data and types, is within the context of each of the unique EditorWorker objects, which is where I've chosen to do the heavy lifting here.
I was hoping and attempting to take advantage of all of the heavy lifting that MSFT has done for us within the MVC framework to handle model binding, but I've come to the conclusion at this point that I don't think that's going to work for us. The solution that I've come up with at this point, is to allow the LoadEditData method of the EditorWorker classes handle loading up the EditData classes for for me. As each EditorWorker class is unique to, and has knowledge of the attribute that it is associated with. The problem I was having originally was that I was letting the EditorWorker.LoadEditData method just return an empty instance of the specific type of EditData class that I needed for the attribute I was currently working with, and let the MVC framework handle model binding to that object for me. That wasn't working because that method is designed to return an object of type IEditData, and I never really knew exactly what type it was that I was currently working with, so I had no way of specifying the type in the call to either of the typed methods: TryUpdateModel<T> or UpdateModel<T>.
So the solution I've come up with, and am going with at least for now (re-education and/or refactoring may very well change this in the future, who knows) is to just pass the Request.Form object into the call to EditorWorker.LoadEditData and let that method handle actually loading up the EditData object that it knows it needs to return for the attribute it's responsible for, which it can do as it knows what information should be in the posted form collection to load up its EditData object.
So that's where I'm at for now. Thanks for the help.

ASP.NET MVC - State and Architecture

After a pair programming session, an interesting question came up which I think I know the answer for.
Question: Is there any other desired way in ASP.NET MVC to retain 'state' other than writing to database or a text file?
I'm going to define state here to mean that we have a collection of person objects, we create a new one, and go to another page, and expect to see the newly created person. (so no Ajax)
My thoughts are we don't want any kung-fu ViewState or other mechanisms, this framework is about going back to a stateless web.
What about user session? There are plenty of valid use cases to store things in session. And what about a distributed caching system like memcached? You also seem to leave out the query string - which is an excellent state saver (?page=2). To me those seem like other desirable methods to save state across requests...?
My thoughts are we don't want any kung-fu ViewState or other mechanisms, this framework is about going back to a stateless web.
The example you provided is pretty easy to do without any sort of "view state kung fu" using capabilities that are already in MVC. "User adds a person and sees that on the next screen." Let me code up a simple PersonController that does exactly what you want:
public ActionResult Add()
{
return View(new Person());
}
[HttpPost]
public ActionResult Add(PersonViewModel myNewPersonViewModel)
{
//validate, user entered everything correctly
if(!ModelState.IsValid)
return View();
//map model to my database/entity/domain object
var myNewPerson = new Person()
{
FirstName = myNewPersonViewModel.FirstName,
LastName = myNewPersonViewModel.LastName
}
// 1. maintains person state, sends the user to the next view in the chain
// using same action
if(MyDataLayer.Save(myNewPerson))
{
var persons = MyDataLayer.GetPersons();
persons.Add(myNewPersion);
return View("PersonGrid", persons);
}
//2. pass along the unique id of person to a different action or controller
//yes, another database call, but probably not a big deal
if(MyDataLayer.Save(myNewPerson))
return RedirecToAction("PersonGrid", ...etc pass the int as route value);
return View("PersonSaveError", myNewPersonViewModel);
}
Now, what I'm sensing is that you want person on yet another page after PersonSaveSuccess or something else. In that case, you probably want to use TempData[""] which is a single serving session and only saves state from one request to another or manage the traditional Session[""] yourself somehow.
What is confusing to me is you're probably going to the db to get all your persons anyway. If you save a person it should be in your persons collection in the next call to your GetPersons(). If you're not using Ajax, than what state are you trying to persist?
ASP.NET MVC offers a cleaner way of working with session storage using model binding. You can write a custom model binder that can supply instances from session to your action methods. Look it up.

Resources