[DataContract]
public class UserDetails
{
string _userid;
string tckimlik;
string ad;
string tarih;
string aciklama;
[DataMember]
public string userid
{
get { return _userid; }
set { _userid = value; }
}
[DataMember]
public string Tckimlik
{
get { return tckimlik; }
set { tckimlik = value; }
}
[DataMember]
public string Ad
{
get { return ad; }
set { ad = value; }
}
[DataMember]
public string Tarih
{
get { return tarih; }
set { tarih = value; }
}
[DataMember]
public string Aciklama
{
get { return aciklama; }
set { aciklama = value; }
}
}
public interface IService1
{
[OperationContract]
List<UserDetails> GetAllPersons();
}
My Class DataContract and OperationContract given above.
My Method GetAllPersons type of List beloew.
public List<UserDetails> GetAllPersons()
{
List<UserDetails> userL = new List<UserDetails>();
try
{
NpgsqlConnection con = new NpgsqlConnection("");
con.Open();
NpgsqlCommand cmd = new NpgsqlCommand("SELECT * FROM RegistrationTable",con);
NpgsqlDataAdapter sda = new NpgsqlDataAdapter(cmd);
NpgsqlDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
UserDetails us = new UserDetails()
{
userid = reader[0].ToString(),
Tckimlik = reader[1].ToString(),
Ad = reader[2].ToString(),
Tarih = reader[3].ToString(),
Aciklama = reader[4].ToString()
};
userL.Add(us);
}
con.Close();
return userL;
}
catch (Exception)
{
throw;
}
}
The Code above is in WCF Service. I want to call GetAllPersons method in Xamarin. But i have trouble with it. My Xamarin code is below.
void getVisitor()
{
List<ServiceReference1.UserDetails> getir = new List<ServiceReference1.UserDetails>();
getir = service.GetAllPersonsAsync();
}
When i wanted to call method in service, i get an error given below.
Severity Code Description Project File Line Suppression State
Error CS0029 Cannot implicitly convert type 'System.Threading.Tasks.Task<ServiceReference1.GetAllPersonsResponse>' to 'System.Collections.Generic.List<ServiceReference1.UserDetails>' XamarinCRUD C:\Users\Eyyub\source\repos\XamarinCRUD\XamarinCRUD\XamarinCRUD\MainPage.xaml.cs 59 Active
Who can hint me, appreciate it!
Best for all!
I also checked logs and no show. Some says that WCF doesnt (de)serialize List return type. Is it true? if yes, what is the solution?. When i used same service through FormApp, works fine. But Xamarin doesnt..
I have implemented an OWIN self-hosted webapi and am trying to use data annotations and an ActionFilterAttribute to return formatted errors to the user. I have set custom error messages on the data annotation but when I try to retrieve the message from the ModelState it is always an empty string (shown in image below).
Model:
public class JobPointer
{
[Required(ErrorMessage = "JobId Required")]
public Guid JobId { get; set; }
}
Filter:
public class ModelValidationFilter : ActionFilterAttribute
{
public override void OnActionExecuting(HttpActionContext actionContext)
{
if (actionContext.ModelState.IsValid) return;
string errors = actionContext.ModelState.SelectMany(state => state.Value.Errors).Aggregate("", (current, error) => current + (error.ErrorMessage + ". "));
actionContext.Response = actionContext.Request.CreateErrorResponse(
HttpStatusCode.BadRequest, errors);
}
}
Endpoint:
[HttpPost]
public HttpResponseMessage DescribeJob(JobPointer jobId)
{
Job job = _jobhelper.GetJob(jobId.JobId);
return Request.CreateResponse(HttpStatusCode.OK, job);
}
Request Body:
{
}
Response:
Status Code: 400
{
"Message": ". "
}
If I change error.Message in ModelValidationFilter to error.Exception.Message I get back the default validation error:
Status Code: 400
{
"Message": "Required property 'JobId' not found in JSON. Path '', line 3, position 2.. "
}
I know this is an old question, but I just had this problem and found the solution myself.
As you no doubt discovered, as Guid is a non-nullable type [Required] produces an unfriendly error message (I assume because the JSON parser picks it up before actually getting the model validation).
You can get around this by making the Guid nullable...
public class JobPointer
{
[Required(ErrorMessage = "JobId Required")]
public Guid? JobId { get; set; }
}
... however, this is not a viable option in all cases (as in my case), so I ended up writing my own validation attribute that would check the property against it's Empty declaration...
public class IsNotEmptyAttribute : ValidationAttribute
{
public override bool IsValid(object value)
{
if (value == null) return false;
var valueType = value.GetType();
var emptyField = valueType.GetField("Empty");
if (emptyField == null) return true;
var emptyValue = emptyField.GetValue(null);
return !value.Equals(emptyValue);
}
}
You could then implement like...
public class JobPointer
{
[IsNotEmpty(ErrorMessage = "JobId Required")]
public Guid JobId { get; set; }
}
I have a client project and a MVC3 EF model first project that exposes a WCF service to the client. I am new to EF and some things are not so clear.
Lets assume the Northwind service with Product entity, if i want to make a simple query like return the products with a specific price, where do i write the code for the query ?
On the server side there is only EDM and the service itself and it is pretty straighforward, hardly any code there.
On the client i have Product model class and NorthwindContext and also a ProdcutsPageViewModel class (it's a MVVM project)
So my question is, How and where do i make queries to the DB ? do i make it from the client side by attaching LINQ code to the URI ? do i make it from the server side by adding new methods to the service ? I would appreciate if you could explain it to a newbie,
Thanks !
Here is some of the code :
On the server, the NorthwindODataService service class:
[ServiceBehavior(IncludeExceptionDetailInFaults = true)]
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class NorthwindODataService : DataService<NorthwindEntities>
{
private readonly IUserPrivilegesRepository userPrivilegesRepository;
private readonly IClaimsIdentity identity;
public NorthwindODataService()
: this(HttpContext.Current.User.Identity as IClaimsIdentity, new InfrastructureEntities())
{
}
public NorthwindODataService(IClaimsIdentity identity, IUserPrivilegesRepository userPrivilegesRepository)
{
this.identity = identity;
this.userPrivilegesRepository = userPrivilegesRepository;
}
protected string UserId
{
get
{
var nameIdentifierClaim = this.identity.Claims.SingleOrDefault(c => c.ClaimType == ClaimTypes.NameIdentifier);
if (nameIdentifierClaim == null)
{
throw new DataServiceException(401, "Unauthorized", "The request requires authentication.", "en-US", null);
}
return nameIdentifierClaim.Value;
}
}
/// <summary>
/// Initializes service-wide policies. This method is called only once.
/// </summary>
/// <param name="config"></param>
public static void InitializeService(DataServiceConfiguration config)
{
config.SetEntitySetAccessRule("Products", EntitySetRights.All);
config.SetEntitySetAccessRule("Categories", EntitySetRights.AllRead);
config.SetEntitySetAccessRule("Suppliers", EntitySetRights.AllRead);
config.SetEntitySetPageSize("Products", 20);
config.SetEntitySetPageSize("Categories", 20);
config.SetEntitySetPageSize("Suppliers", 20);
config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2;
config.UseVerboseErrors = true;
}
/// <summary>
/// Define a query interceptor for the Products entity set.
/// </summary>
/// <returns></returns>
[QueryInterceptor("Products")]
public Expression<Func<Product, bool>> OnQueryProducts()
{
this.ValidateAuthorization("Products", PrivilegeConstants.SqlReadPrivilege);
// The user has Read permission.
return p => true;
}
/// <summary>
/// Define a query interceptor for the Categories entity set.
/// </summary>
/// <returns></returns>
[QueryInterceptor("Categories")]
public Expression<Func<Category, bool>> OnQueryCategories()
{
this.ValidateAuthorization("Categories", PrivilegeConstants.SqlReadPrivilege);
// The user has Read permission.
return p => true;
}
/// <summary>
/// Define a query interceptor for the Suppliers entity set.
/// </summary>
/// <returns></returns>
[QueryInterceptor("Suppliers")]
public Expression<Func<Supplier, bool>> OnQuerySuppliers()
{
this.ValidateAuthorization("Suppliers", PrivilegeConstants.SqlReadPrivilege);
// The user has Read permission.
return p => true;
}
/// <summary>
/// Define a change interceptor for the Products entity set.
/// </summary>
/// <param name="product"></param>
/// <param name="operations"></param>
[ChangeInterceptor("Products")]
public void OnChangeProducts(Product product, UpdateOperations operations)
{
if (operations == UpdateOperations.Change)
{
this.ValidateAuthorization("Products", PrivilegeConstants.SqlUpdatePrivilege);
var entry = default(ObjectStateEntry);
if (this.CurrentDataSource.ObjectStateManager.TryGetObjectStateEntry(product, out entry))
{
// Reject changes to a discontinued Product.
// Because the update is already made to the entity by the time the
// change interceptor in invoked, check the original value of the Discontinued
// property in the state entry and reject the change if 'true'.
if ((bool)entry.OriginalValues["Discontinued"])
{
throw new DataServiceException(400, "Bad Request", "A discontinued product cannot be modified.", "en-US", null);
}
}
else
{
throw new DataServiceException(404, "Not Found", "The requested product could not be found in the data source.", "en-US", null);
}
}
else if (operations == UpdateOperations.Add)
{
this.ValidateAuthorization("Products", PrivilegeConstants.SqlCreatePrivilege);
}
else if (operations == UpdateOperations.Delete)
{
this.ValidateAuthorization("Products", PrivilegeConstants.SqlDeletePrivilege);
var entry = default(ObjectStateEntry);
if (this.CurrentDataSource.ObjectStateManager.TryGetObjectStateEntry(product, out entry))
{
// Only a discontinued Product can be deleted.
if (!(bool)entry.OriginalValues["Discontinued"])
{
throw new DataServiceException(400, "Bad Request", "Products that are not discontinued cannot be deleted.", "en-US", null);
}
}
else
{
throw new DataServiceException(404, "Not Found", "The requested product could not be found in the data source.", "en-US", null);
}
}
}
private static string BuildMessage(string entitySetName, string privilege)
{
var message = string.Empty;
switch (privilege)
{
case PrivilegeConstants.SqlCreatePrivilege:
message = string.Format(CultureInfo.InvariantCulture, "You are not authorized to create new rows in the {0} entity set.", entitySetName);
break;
case PrivilegeConstants.SqlReadPrivilege:
message = string.Format(CultureInfo.InvariantCulture, "You are not authorized to query the {0} entity set.", entitySetName);
break;
case PrivilegeConstants.SqlUpdatePrivilege:
message = string.Format(CultureInfo.InvariantCulture, "You are not authorized to update rows in the {0} entity set.", entitySetName);
break;
case PrivilegeConstants.SqlDeletePrivilege:
message = string.Format(CultureInfo.InvariantCulture, "You are not authorized to delete rows in the {0} entity set.", entitySetName);
break;
default:
message = string.Format(CultureInfo.InvariantCulture, "You are not authorized to access the {0} entity set.", entitySetName);
break;
}
return message;
}
private void ValidateAuthorization(string entitySetName, string privilege)
{
if (!this.userPrivilegesRepository.HasUserPrivilege(this.UserId, privilege))
{
// The user does not have Read permission.
throw new DataServiceException(401, "Unauthorized", BuildMessage(entitySetName, privilege), "en-US", null);
}
}
}
}
on the client, the Product model class:
[EntitySetAttribute("Products")]
[DataServiceKeyAttribute("ProductID")]
public class Product : INotifyPropertyChanged
{
private int id;
private string productName;
private int? supplierID;
private int? categoryID;
private string quantityPerUnit;
private decimal? unitPrice;
private short? unitsInStock;
private short? unitsOnOrder;
private short? reorderLevel;
private bool discontinued;
public event PropertyChangedEventHandler PropertyChanged;
public int ProductID
{
get
{
return this.id;
}
set
{
this.id = value;
this.OnPropertyChanged("ProductID");
}
}
public string ProductName
{
get
{
return this.productName;
}
set
{
this.productName = value;
this.OnPropertyChanged("ProductName");
}
}
public int? SupplierID
{
get
{
return this.supplierID;
}
set
{
this.supplierID = value;
this.OnPropertyChanged("SupplierID");
}
}
public int? CategoryID
{
get
{
return this.categoryID;
}
set
{
this.categoryID = value;
this.OnPropertyChanged("CategoryID");
}
}
public string QuantityPerUnit
{
get
{
return this.quantityPerUnit;
}
set
{
this.quantityPerUnit = value;
this.OnPropertyChanged("QuantityPerUnit");
}
}
public decimal? UnitPrice
{
get
{
return this.unitPrice;
}
set
{
this.unitPrice = value;
this.OnPropertyChanged("UnitPrice");
}
}
public short? UnitsInStock
{
get
{
return this.unitsInStock;
}
set
{
this.unitsInStock = value;
this.OnPropertyChanged("UnitsInStock");
}
}
public short? UnitsOnOrder
{
get
{
return this.unitsOnOrder;
}
set
{
this.unitsOnOrder = value;
this.OnPropertyChanged("UnitsOnOrder");
}
}
public short? ReorderLevel
{
get
{
return this.reorderLevel;
}
set
{
this.reorderLevel = value;
this.OnPropertyChanged("ReorderLevel");
}
}
public bool Discontinued
{
get
{
return this.discontinued;
}
set
{
this.discontinued = value;
this.OnPropertyChanged("Discontinued");
}
}
public static Product CreateProduct(int productID, string productName, bool discontinued)
{
return new Product
{
ProductID = productID,
ProductName = productName,
Discontinued = discontinued,
};
}
protected virtual void OnPropertyChanged(string changedProperty)
{
var propertyChanged = this.PropertyChanged;
if (propertyChanged != null)
{
propertyChanged(this, new PropertyChangedEventArgs(changedProperty));
}
}
}
}
And the NorthwindContext class:
public class NorthwindContext : DataServiceContext
{
public NorthwindContext(Uri serviceRoot)
: base(serviceRoot)
{
this.MergeOption = MergeOption.OverwriteChanges;
this.SaveChangesDefaultOptions = SaveChangesOptions.ContinueOnError;
}
public void AddToCategories(Category category)
{
this.AddObject("Categories", category);
}
public void AddToProducts(Product product)
{
this.AddObject("Products", product);
}
public void AddToSuppliers(Supplier supplier)
{
this.AddObject("Suppliers", supplier);
}
public void AttachToCategories(Category category)
{
this.AttachTo("Categories", category);
}
public void AttachToProducts(Product product)
{
this.AttachTo("Products", product);
}
public void AttachToSuppliers(Supplier supplier)
{
this.AttachTo("Suppliers", supplier);
}
}
}
and here is the ProductsPageViewModel class :
public class ProductsPageViewModel : ListViewModel<Product>
{
public ProductsPageViewModel()
: this(Deployment.Current.Dispatcher, App.CloudClientFactory.ResolveNorthwindContext())
{
}
public ProductsPageViewModel(Dispatcher dispatcher, NorthwindContext northwindContext)
: base(dispatcher, northwindContext)
{
}
protected override string EntitySetName
{
get
{
return "Products";
}
}
}
}
When you are working with EF, it doesn't suppose any direct queries to the database. Spent some time reading what is Domain Driven Design. There is described strategy Persistent Ignorance, which means, that when you are designing your system you should not consider data storage at all. Work only with the model. Data Mapper pattern describes the place where all the things related with the database should be done. Here is good article, which I think can help you.
Another advice, do not forget that MVC supports restful style of Web Development. Leveraging these capabilities should be helpful in your design.
paramosh,
So are you able to explain it to a newbie or not? I just went to that website, and read through that page, but it wasn't really much help for trying to lean the EF network (it's mainly reinforcing how I did things prior to EF).
I'm using WCF for communication between various .NET applications. These services are all on the same private subnet, so I'd like to avoid the complexity and performance overhead of encryption and certificates. I do, however, need basic username/password support since the requests are all authenticated against our custom MembershipProvider.
We are currently using HTTP with Clear Username Binding and that is working well. However, I would like to use TCP to improve performance. Is it possible to do simple username/password authentication (the way Clear Username Binding does) over NetTcpBinding without having to use certificates, encryption, etc?
The solution I ended up going with was modifying Clear Username Binding to use TCP for transport and binary message encoding. I got the idea from a series of comments on the author's blog. The complete code for my binding is below:
using System;
using System.Configuration;
using System.Net.Security;
using System.ServiceModel.Channels;
using System.ServiceModel.Configuration;
namespace ClearTcpBinding
{
public class ClearTcpBinding : CustomBinding
{
private long _maxReceivedMessageSize = 65536;
public void SetMaxReceivedMessageSize(long value)
{
_maxReceivedMessageSize = value;
}
public override BindingElementCollection CreateBindingElements()
{
var res = new BindingElementCollection
{
new BinaryMessageEncodingBindingElement {MessageVersion = MessageVersion.Soap12WSAddressing10},
SecurityBindingElement.CreateUserNameOverTransportBindingElement(),
new AutoSecuredTcpTransportElement {MaxReceivedMessageSize = _maxReceivedMessageSize}
};
return res;
}
public override string Scheme { get { return "net.tcp"; } }
}
public class ClearTcpBindingElement : StandardBindingElement
{
private ConfigurationPropertyCollection _properties;
protected override void OnApplyConfiguration(Binding binding)
{
var b = (ClearTcpBinding)binding;
b.SetMaxReceivedMessageSize(Convert.ToInt64(MaxReceivedMessageSize));
}
protected override Type BindingElementType
{
get { return typeof(ClearTcpBinding); }
}
protected override ConfigurationPropertyCollection Properties
{
get
{
if (_properties == null)
{
var properties = base.Properties;
properties.Add(new ConfigurationProperty("maxReceivedMessageSize", typeof(string), "65536"));
_properties = properties;
}
return _properties;
}
}
public string MaxReceivedMessageSize
{
get { return (string)base["maxReceivedMessageSize"]; }
set { base["maxReceivedMessageSize"] = value; }
}
}
public class ClearTcpCollectionElement
: StandardBindingCollectionElement<ClearTcpBinding, ClearTcpBindingElement>
{
}
public class AutoSecuredTcpTransportElement : TcpTransportBindingElement, ITransportTokenAssertionProvider
{
public override T GetProperty<T>(BindingContext context)
{
if (typeof(T) == typeof(ISecurityCapabilities))
return (T)(ISecurityCapabilities)new AutoSecuredTcpSecurityCapabilities();
return base.GetProperty<T>(context);
}
public System.Xml.XmlElement GetTransportTokenAssertion()
{
return null;
}
}
public class AutoSecuredTcpSecurityCapabilities : ISecurityCapabilities
{
public ProtectionLevel SupportedRequestProtectionLevel { get { return ProtectionLevel.EncryptAndSign; } }
public ProtectionLevel SupportedResponseProtectionLevel { get { return ProtectionLevel.EncryptAndSign; } }
public bool SupportsClientAuthentication { get { return false; } }
public bool SupportsClientWindowsIdentity { get { return false; } }
public bool SupportsServerAuthentication { get { return true; } }
}
}
I'm trying to get hold of an object from another application using WCF. With built in classes it works fine but I run into probems when trying to return a custom interface type from the WCF operation.
Whether I include the interface in both applications separately, or specif it as a shared assembly, I get the same result: a CommunicationException with the message "There was an error reading from the pipe: Unrecognized error 109".
The interface looks like this:
[ServiceContract]
public interface IBase {
int IntTest {
[OperationContract]
get;
}
String StringTest {
[OperationContract]
get;
}
IOther OtherTest {
[OperationContract]
get;
}
}
[ServiceContract]
public interface IOther {
String StringTest {
[OperationContract]
get;
}
}
My server looks like this:
public partial class MainWindow : Window {
private Base fb;
private ServiceHost host;
public MainWindow() {
InitializeComponent();
fb = new Base();
host = new ServiceHost(fb, new Uri[] { new Uri("net.pipe://localhost") });
host.AddServiceEndpoint(typeof(IBase), new NetNamedPipeBinding(),
"PipeReverse");
host.Open();
}
private void Window_Closing(object sender, CancelEventArgs e) {
host.Close();
}
}
And here is my implementation of the interface:
[Serializable]
[ServiceBehavior(InstanceContextMode=InstanceContextMode.Single)]
public class Base : MarshalByRefObject, IBase {
public int IntTest {
get { return 4; }
}
public string StringTest {
get { return "A string from Base"; }
}
public IOther OtherTest {
get { return new Other(); }
}
}
[Serializable]
[DataContract]
public class Other : MarshalByRefObject, IOther {
[DataMember]
public string StringTest {
get { return "A string from Other"; }
}
}
The client looks like this:
public partial class Form1 : Form {
IBase obj;
public Form1() {
InitializeComponent();
ChannelFactory<IBase> pipeFactory = new ChannelFactory<IBase>(
new NetNamedPipeBinding(), new EndpointAddress(
"net.pipe://localhost/PipeReverse"));
obj = pipeFactory.CreateChannel();
}
private void button2_Click(object sender, EventArgs e) {
Console.WriteLine("Returns: " + obj.StringTest + " " +
obj.StringTest.Length);
Console.WriteLine("Returns: " + obj.IntTest);
Console.WriteLine(obj.OtherTest);
}
}
Everything works like a charm except this line:
Console.WriteLine(obj.OtherTest);
It give me a CommunicationException with the message "There was an error reading from the pipe: Unrecognized error 109". As far as I can tell that is a broken pipe due to a faulted state but I can't figure out why, or more importantly how to fix it. Any ideas?
I have no config file as everthing is done in the code above so I don't know how to turn on tracing, otherwise I would have included that too.
The returned property OtherTest needs to be a concrete type and not an interface, otherwise the serialization will not work.
This is typically a serialization error. Look to the [KnownType] attribute. The easiest way to test this out is to invoke the DataContractSerializer directly. You can use its WriteObject and ReadObject methods to get the true serialization errors. You can also inspect the stream(FileStream usually) to make sure you type serializes correctly.