My first time using .net core.
I was able to build a functioning ,net core web application that calls data from my SQL server using Onion Layers. My layout is as below:
Architecture
Core
Application Services
Domain Services
Core.Entity
Infrastructure
UI
API
CemeteryAPI
Web
MVC Web Application
My HomeController has a PageModel with a Complex Type of Search, which consists of about 5 or so ints another 5-6 Lists. In the past I would have done:
var model = new Models.HomePageModel
{
Search = new Business.Search()
};
public partial class Search
{
public String Surname { get; set; }
public String Forename { get; set; }
public String Initials { get; set; }
//etc.
}
I have registered my Services on my startup in ConfigureServices and have attempted to inject this way
Startup.cs
public void ConfigureServices(IServiceCollection services)
{
services.AddScoped<ICemeteryRepository, CemeteryRepository>();
services.AddScoped<ICountryRepository, CountryRepository>();
//etc
services.AddScoped<ICemeteryService, CemeteryService>();
services.AddScoped<ICountryService, CountryService>();
}
CemeteryService
//ApplicationService
public class CemeteryService : AbstractUnitOfWorkService, ICemeteryService
{
public CemeteryService(IUnitOfWork uow) : base(uow) { }
public int Count()
{
return _unitOfWork.CemeteryRepository.Count();
}
public Cemetery Get(int id)
{
return _unitOfWork.CemeteryRepository.Get(id);
}
public List<Cemetery> List()
{
return _unitOfWork.CemeteryRepository.GetAll().ToList();
}
}
ICemeterRepository
//DomainService
public interface ICemeteryRepository : IRepository<Cemetery>
{
}
CemeteryRepository
public class CemeteryRepository : BaseRepository, ICemeteryRepository
{
public CemeteryRepository(SAWGPDBContext context) : base(context) { }
public int Count()
{
return _context.Cemetery.Count();
}
public Cemetery Get(int id)
{
return _context.Cemetery.Find(id);
}
public IEnumerable<Cemetery> GetAll()
{
return _context.Cemetery;
}
//etc
}
ICemeteryInterface
public interface ICemeteryService
{
int Count();
List<Cemetery> List();
//etc
}
public ActionResult Index([FromServices] ICasualtyService _CasualtyService, IPhotoService _PhotoService, ICountryService _CountryService, ICemeteryService _CemeteryService, IRegimentService _RegimentService)
var model = new Models.HomePageModel
{
Search = new SearchPageModel(_PhotoService, _CasualtyService, _CountryService, _CemeteryService, _RegimentService, )
};
This looked wrong but I couldn't find any proper examples as I wasn't sure what to look for exactly. The above returns
Model bound complex types must not be abstract or value types and must
have a parameterless constructor.
I presume I need to build a SearchService but I'm not entirely clear how to build one for a complex type. Any pointers would be appreciated.
Related
when i put fluent validators in asp.net core client side validation project exactly work
but when i put validator in class library not work
My model and validator in class library :
using FluentValidation;
namespace ClassLibrary1
{
public class Person
{
public string Name { get; set; }
public string Family { get; set; }
public int Age { get; set; }
}
public class PersonValidator : AbstractValidator<Person>
{
public PersonValidator()
{
RuleFor(c => c.Name).NotEmpty().WithMessage("Name Is Empty");
}
}
}
In program.cs file :
services.AddFluentValidationAutoValidation(M =>
{
M.DisableDataAnnotationsValidation = true;
}).AddFluentValidationClientsideAdapters()
.AddValidatorsFromAssemblyContaining<PersonValidator>();
I can't reproduce the issue, and it works in my side, I will show my test steps.
Steps
my project structure.
The person.cs code same as yours
The program.cs code same as yours
My test method in Controller.
[HttpPost]
[Route("Test")]
public IActionResult Test([FromBody]Person model)
{
if (!ModelState.IsValid) //<----Validate here
{
return new BadRequestObjectResult(ModelState);
}
return Ok();
//Other Code..
}
Test result and it works.
I found the solution.
When the class library is nullable, the client-side validation in ASP.NET Core does not work.
Solution:
Remove <Nullable>enable</Nullable> from the *.csproj
Define nullable property:
public string? name{get;set}
I tried to convert ASP.NET WEB API to ASP.NET CORE WEB API and have errors
My code in ASP.NET WebAPI
public class TestController : ApiController
{
// GET /test
public object Get()
{
return "get";
}
// GET /test?id={id}
public object Get(string id)
{
return id;
}
// GET /test?id={id}&anyParam={anyParam}
public object Get(string id, string anyParam)
{
return id + anyParam;
}
}
config.Routes.MapHttpRoute("Controller", "{controller}");
Try to convert it to ASP.NET Core 2.1 / 3.0
[ApiController]
[Route("{controller}")]
public class TestController : ControllerBase
{
// GET /test
public object Get()
{
return "get";
}
// GET /test?id={id}
public object Get(string id)
{
return id;
}
// GET /test?id={id}&anyParam={anyParam}
public object Get(string id, string anyParam)
{
return id + anyParam;
}
}
services.AddControllers();
app.UseRouting();
app.UseEndpoints(endpoints => { endpoints.MapControllers(); });
And i have in ASP.NET Core
AmbiguousMatchException: The request matched multiple endpoints
The sensible solution is just have one method that takes three parameters.
But, sensible solutions don't make for the most interesting stackoverflow answers, so here is how you can do this with two custom attributes, one which states the parameters that are required, and another which states which parameters are excluded:
public class RequireRequestParameterAttribute : ActionMethodSelectorAttribute
{
private readonly string[] _requiredNames;
public RequireRequestParameterAttribute(params string[] names)
{
this._requiredNames = names;
}
public override bool IsValidForRequest(
RouteContext routeContext,
ActionDescriptor action
) =>
this._requiredNames
.All(
routeContext
.HttpContext
.Request
.Query
.ContainsKey
);
}
public class DisallowRequestParameterAttribute : ActionMethodSelectorAttribute
{
private readonly string[] _forbiddenNames;
public DisallowRequestParameterAttribute(params string[] names)
{
this._forbiddenNames = names;
}
public override bool IsValidForRequest(
RouteContext routeContext,
ActionDescriptor action
) =>
!(this._forbiddenNames
.Any(
routeContext
.HttpContext
.Request
.Query
.ContainsKey
)
);
}
Now you can apply the attributes as follows:
[ApiController]
[Route("[controller]")]
public class TestController : ControllerBase
{
// GET test
public object Get()
{
return "Get";
}
// GET test?id={id}
[RequireRequestParameter("id")]
[DisallowRequestParameter("anyParam")]
public object Get(string id)
{
return id;
}
// GET test?id={id}&anyParam={anyParam}
[RequireRequestParameter("id", "anyParam")]
public object Get(string id, string anyParam)
{
return $"{id}: {anyParam}";
}
}
This means if you add another method with a third parameter, you have the maintenance burden of adding or modifying the DisallowRequestParameter attribute on the other methods.
I look your generated urls on actions and they are both /test which cause AmbiguousMatchException because your parameters are GET and are optional.
I think you can have same names on actions but you need define different ROUTE attribute (diff urls) on actions. Eg. you can not use default route with polymorphism on controller actions.
[Route("Home/About")]
MVC controllers Mapping of controllers now takes place inside
UseEndpoints.
Add MapControllers if the app uses attribute routing.
Source
https://learn.microsoft.com/cs-cz/aspnet/core/mvc/controllers/routing?view=aspnetcore-3.0#attribute-routing
Thanks to daremachine with his answer I was able to find information on Google
First step in ASP.NET Core we need class which inherit ActionMethodSelectorAttribute
public class RequireRequestValueAttribute : ActionMethodSelectorAttribute
{
public RequireRequestValueAttribute(string name, string value = null)
{
Name = name;
Value = value;
}
public string Name { get; }
public string Value { get; }
public StringComparison ComparisonType { get; } = StringComparison.OrdinalIgnoreCase;
private bool ValueIsValid(object value)
{
return ValueIsValid(value?.ToString());
}
private bool ValueIsValid(string value)
{
if (Value == null)
{
return true;
}
return string.Equals(value, Value, ComparisonType);
}
public override bool IsValidForRequest(RouteContext routeContext, ActionDescriptor action)
{
var value = default(object);
if (routeContext.RouteData.Values.TryGetValue(Name, out value) && ValueIsValid(value))
return true;
if (routeContext.RouteData.DataTokens.TryGetValue(Name, out value) && ValueIsValid(value))
return true;
if (routeContext.HttpContext.Request.Query.ContainsKey(Name))
{
var values = routeContext.HttpContext.Request.Query[Name];
if (values.Count <= 0)
{
if (ValueIsValid(null))
return true;
}
else if (values.Any(v => ValueIsValid(v)))
return true;
}
return false;
}
}
Then we can add to question methods [RequireRequestValue("")], the controller will look like this
[ApiController]
[Route("{controller}")]
public class TestController : ControllerBase
{
// GET /test
public object Get()
{
return "get";
}
// GET /test?id={id}
[RequireRequestValue("id")]
public object Get(string id)
{
return id;
}
}
But it can't polymorphism two similar fields, type id in my question
For asp net core 2. If you try to implement the same logic as was in web api controllers then use Microsoft.AspNetCore.Mvc.WebApiCompatShim. This nuget package provides compatibility in ASP.NET Core MVC with ASP.NET Web API 2 to simplify migration of existing Web API implementations. Please check this answer. Starting with ASP.NET Core 3.0, the Microsoft.AspNetCore.Mvc.WebApiCompatShim package is no longer available.
We have a problem concerning Entity Framework objects and sending them through WCF.
We have a database, and Entity Framework created classes from that database, a 'Wallet' class in this particular situation.
We try to transfer a Wallet using this code:
public Wallet getWallet()
{
Wallet w = new Wallet();
w.name = "myname";
w.walletID = 123;
return w;
}
We need to transfer that Wallet class, but it won't work, we always encounter the same exception:
"An error occurred while receiving the HTTP response to localhost:8860/ComplementaryCoins.svc. This could be due to the service endpoint binding not using the HTTP protocol. This could also be due to an HTTP request context being aborted by the server (possibly due to the service shutting down). See server logs for more details."
We searched on the internet, and there is a possibility that the error is due to the need of serialization of Entity Framework-objects.
We have absolutely no idea if this could be the case, and if this is the case, how to solve it.
Our DataContract looks like this (very simple):
[DataContract]
public partial class Wallet
{
[DataMember]
public int getwalletID { get { return walletID; } }
[DataMember]
public string getname { get { return name; } }
}
Does anyone ever encountered this problem?
EDIT: Our Entity Framework created class looks like this:
namespace ComplementaryCoins
{
using System;
using System.Collections.Generic;
public partial class Wallet
{
public Wallet()
{
this.Transaction = new HashSet<Transaction>();
this.Transaction1 = new HashSet<Transaction>();
this.User_Wallet = new HashSet<User_Wallet>();
this.Wallet_Item = new HashSet<Wallet_Item>();
}
public int walletID { get; set; }
public string name { get; set; }
public virtual ICollection<Transaction> Transaction { get; set; }
public virtual ICollection<Transaction> Transaction1 { get; set; }
public virtual ICollection<User_Wallet> User_Wallet { get; set; }
public virtual ICollection<Wallet_Item> Wallet_Item { get; set; }
}
}
Thanks for helping us.
I had the same problem some time ago and the solution for this was:
The entity framework was returning a serialized class instead of normal class.
eg. Wallet_asfawfklnaewfklawlfkawlfjlwfejlkef instead of Wallet
To solve that you can add this code:
base.Configuration.ProxyCreationEnabled = false;
in your Context file.
Since the context file is auto generated you can add it in the Context.tt
In the Context.tt file it can be added around lines 55-65:
<#=Accessibility.ForType(container)#> partial class <#=code.Escape(container)#> : DbContext
{
public <#=code.Escape(container)#>()
: base("name=<#=container.Name#>")
{
base.Configuration.ProxyCreationEnabled = false;
<#
if (!loader.IsLazyLoadingEnabled(container))
{
#>
this.Configuration.LazyLoadingEnabled = false;
<#
Try specifying a setter for the properties, something like this :
[DataContract]
public partial class Wallet
{
[DataMember]
public int getwalletID { get { return walletID; } set { } }
[DataMember]
public string getname { get { return name; } set { } }
}
If it still doesn't work, you may consider creating an intermediate POCO class for this purpose, and use mapper library like AutoMapper or ValueInjecter to transfer the data from the EF objects.
The POCO class should have same properties as your EF class :
[DataContract]
public class WalletDTO
{
[DataMember]
public int walletID { get; set; }
[DataMember]
public string name { get; set; }
}
And modify your method to return this class instead :
public WalletDTO getWallet()
{
Wallet w = new Wallet(); // or get it from db using EF
var dto = new WalletDTO();
//assuming we are using ValueInjecter, this code below will transfer all matched properties from w to dto
dto.InjectFrom(w);
return dto;
}
Are you trying to recieve a IEnumerable<Wallets>? If - yes, please modify your server class that returns the IEnumerable by adding .ToArray() method
I want to enforce some rules every time a domain object is saved but i don't know the best way to achieve this. As, i see it, i have two options: add a save method to the domain object, or handle the rules before saving in the application layer. See code sample below:
using System;
namespace Test
{
public interface IEmployeeDAL
{
void Save(Employee employee);
Employee GetById(int id);
}
public class EmployeeDALStub : IEmployeeDAL
{
public void Save(Employee employee)
{
}
public Employee GetById(int id)
{
return new Employee();
}
}
public interface IPermissionChecker
{
bool IsAllowedToSave(string user);
}
public class PermissionCheckerStub : IPermissionChecker
{
public bool IsAllowedToSave(string user)
{
return false;
}
}
public class Employee
{
public virtual IEmployeeDAL EmployeeDAL { get; set; }
public virtual IPermissionChecker PermissionChecker { get; set; }
public int Id { get; set; }
public string Name { get; set; }
public void Save()
{
if (PermissionChecker.IsAllowedToSave("the user")) // Should this be called within EmployeeDAL?
EmployeeDAL.Save(this);
else
throw new Exception("User not permitted to save.");
}
}
public class ApplicationLayerOption1
{
public virtual IEmployeeDAL EmployeeDAL { get; set; }
public virtual IPermissionChecker PermissionChecker { get; set; }
public ApplicationLayerOption1()
{
//set dependencies
EmployeeDAL = new EmployeeDALStub();
PermissionChecker = new PermissionCheckerStub();
}
public void UnitOfWork()
{
Employee employee = EmployeeDAL.GetById(1);
//set employee dependencies (it doesn't seem correct to set these in the DAL);
employee.EmployeeDAL = EmployeeDAL;
employee.PermissionChecker = PermissionChecker;
//do something with the employee object
//.....
employee.Save();
}
}
public class ApplicationLayerOption2
{
public virtual IEmployeeDAL EmployeeDAL { get; set; }
public virtual IPermissionChecker PermissionChecker { get; set; }
public ApplicationLayerOption2()
{
//set dependencies
EmployeeDAL = new EmployeeDALStub();
PermissionChecker = new PermissionCheckerStub();
}
public void UnitOfWork()
{
Employee employee = EmployeeDAL.GetById(1);
//do something with the employee object
//.....
SaveEmployee(employee);
}
public void SaveEmployee(Employee employee)
{
if (PermissionChecker.IsAllowedToSave("the user")) // Should this be called within EmployeeDAL?
EmployeeDAL.Save(employee);
else
throw new Exception("User not permitted to save.");
}
}
}
What do you do in this situation?
I would prefer the second approach where there's a clear separation between concerns. There's a class responsible for the DAL, there's another one responsible for validation and yet another one for orchestrating these.
In your first approach you inject the DAL and the validation into the business entity. Where I could argue if injecting a validator into the entity could be a good practice, injecting the DAL into the business entity is is definitely not a good practive IMHO (but I understand that this is only a demonstration and in a real project you would at least use a service locator for this).
If I had to choose, I'd choose the second option so that my entities were not associated to any DAL infrastructure and purely focused on the domain logic.
However, I don't really like either approach. I prefer taking more of an AOP approach to security & roles by adding attributes to my application service methods.
The other thing I'd change is moving away from the 'CRUD' mindset. You can provide much granular security options if you secure against specific commands/use cases. For example, I'd make it:
public class MyApplicationService
{
[RequiredCommand(EmployeeCommandNames.MakeEmployeeRedundant)]
public MakeEmployeeRedundant(MakeEmployeeRedundantCommand command)
{
using (IUnitOfWork unitOfWork = UnitOfWorkFactory.Create())
{
Employee employee = _employeeRepository.GetById(command.EmployeeId);
employee.MakeRedundant();
_employeeRepository.Save();
}
}
}
public void AssertUserHasCorrectPermission(string requiredCommandName)
{
if (!Thread.CurrentPrincipal.IsInRole(requiredCommandName))
throw new SecurityException(string.Format("User does not have {0} command in their role", requiredCommandName));
}
Where you'd intercept the call to the first method and invoke the second method passing the thing that they must have in their role.
Here's a link on how to use unity for intercepting: http://litemedia.info/aop-in-net-with-unity-interception-model
Where to put the save/pre save methods in a domain object?
Domain objects are persistent-ignorant in DDD. They are unaware of the fact that sometimes they get 'frozen' transported to some storage and then restored. They do not notice that. In other words, domain objects are always in a 'valid' and savable state.
Permission should also be persistent-ignorant and based on domain and Ubiquitous Language, for example:
Only users from Sales group can add OrderLines to an Order in a
Pending state
As opposed to:
Only users from Sales group can save Order.
The code can look like this:
internal class MyApplication {
private IUserContext _userContext;
private ICanCheckPermissions _permissionChecker;
public void AddOrderLine(Product p, int quantity, Money price, ...) {
if(!_permissionChecker.IsAllowedToAddOrderLines(_userContext.CurrentUser)) {
throw new InvalidOperationException(
"User X is not allowed to add order lines to an existing order");
}
// add order lines
}
}
I'm wondering about a "best practice" using NHibernate, AutoMapper and ASP.NET MVC. Currently, i'm using :
class Entity
{
public int Id { get; set; }
public string Label { get; set; }
}
class Model
{
public int Id { get; set; }
public string Label { get; set; }
}
Entity and model are mapped like this :
Mapper.CreateMap<Entity,Model>();
Mapper.CreateMap<Model,Entity>()
.ConstructUsing( m => m.Id == 0 ? new Entity() : Repository.Get( m.Id ) );
And in the controller :
public ActionResult Update( Model mdl )
{
// IMappingEngine is injected into the controller
var entity = this.mappingEngine.Map<Model,Entity>( mdl );
Repository.Save( entity );
return View(mdl);
}
Is this correct, or can it be improved ?
that's how I was doing in a project:
public interface IBuilder<TEntity, TInput>
{
TInput BuildInput(TEntity entity);
TEntity BuildEntity(TInput input);
TInput RebuildInput(TInput input);
}
implement this interface for each entity or/and for some group of entities you could do a generic one and use it in each controller; use IoC;
you put your mapping code in the first 2 methods (doesn't matter the mapping technology, you could even do it by hand)
and the RebuildInput is for when you get the ModelState.IsValid == false, just call BuildEntity and BuildInput again.
and the usage in the controller:
public ActionResult Create()
{
return View(builder.BuildInput(new TEntity()));
}
[HttpPost]
public ActionResult Create(TInput o)
{
if (!ModelState.IsValid)
return View(builder.RebuildInput(o));
repo.Insert(builder.BuilEntity(o));
return RedirectToAction("index");
}
I actually do sometimes generic controller that is used for more entities
like here: asp.net mvc generic controller
EDIT:
you can see this technique in an asp.net mvc sample application here:
http://prodinner.codeplex.com
I would inject the IMappingEngine into the controller, instead of the using the static Mapper class. You then get all the benefits of being able to mock this in your tests.
Take a look at this link by AutoMapper's creator,
http://www.lostechies.com/blogs/jimmy_bogard/archive/2009/05/11/automapper-and-ioc.aspx