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Implementing IEnumerable in WCF

I'm learning about WCF, and made a C# fiddle of custom class in the interface that has its own GetEnumerator() method to customize the class' foreach behaviour. The class is as shown:
ProductClass.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Collections;
namespace ProductInterfaces
{
public class ProductData : IEnumerable
{
public string Name { get; set; }
public string ProductNumber { get; set; }
public string Color { get; set; }
public double ListPrice { get; set; }
List<string> myData = new List<string>(new string[] { "test1", "test2", "test3", "test4" });
public IEnumerator<string> GetEnumerator()
{
foreach(string val in myData)
{
yield return val;
}
}
IEnumerator IEnumerable.GetEnumerator()
{
return GetEnumerator();
}
}
}
And the contract is as shown (IWCFProductService.cs):
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;
namespace ProductInterfaces
{
// NOTE: You can use the "Rename" command on the "Refactor" menu to change the interface name "IWCFProductService" in both code and config file together.
[ServiceContract]
public interface IWCFProductService
{
[OperationContract]
ProductData GetProduct(string productNumber);
}
}
The implementation of the GetProduct() method is as shown:
using ProductInterfaces;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;
namespace ProductService
{
public class WCFProductService : IWCFProductService
{
public ProductData GetProduct(string productNumber)
{
using (adventureworksEntities database = new adventureworksEntities())
{
var table_of_products = database.products;
ProductData desired_product = new ProductData();
foreach (var p in table_of_products)
{
if (p.ProductNumber == productNumber)
{
Console.WriteLine("Test using a custom foreach of ProductData class");
foreach (string i in desired_product)
{
Console.WriteLine(i);
}
desired_product.Name = p.Name;
desired_product.ProductNumber = p.ProductNumber;
desired_product.Color = p.Color;
desired_product.ListPrice = p.ListPrice;
return desired_product;
}
}
throw new Exception();
}
}
}
}
When called by the client:
using ProductInterfaces;
using System;
using System.Collections.Generic;
using System.Linq;
using System.ServiceModel;
using System.Text;
using System.Threading.Tasks;
namespace ProductClient
{
class Program
{
static void Main(string[] args)
{
// Client creates channel factory by passing in the name of the endpoint (i.e. ProductServiceEndpoint)
ChannelFactory<IWCFProductService> channelFactory = new ChannelFactory<IWCFProductService>("ProductServiceEndpoint");
// Create a proxy i.e. create a channel
IWCFProductService proxy = channelFactory.CreateChannel();
Console.WriteLine("Input product name to be searched:");
string input = Console.ReadLine();
var searchResult = proxy.GetProduct(input);
Console.WriteLine(searchResult.Name);
Console.ReadLine();
}
}
}
It fails at var searchResult = proxy.GetProduct(input);, with exception saying
System.ServiceModel.CommunicationException: 'An error occurred while receiving the HTTP response to http://localhost:9999/ProductService. 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.'
I did some trial and error, and if I remove IEnumerable and the foreach loop, there is no issue and searchResult is a valid object. Why is this happening? Am I understanding something wrong?

I think it should be a serialization issue, WCF needs to have concrete classes to pass data.
It cannot return IEnumerable - try using List (or T[] array) or concrete types.
You can also use the Service Trace Viewer to find specific issues.
Posts with similar questions
WCF Web Service error: "Service endpoint binding not using HTTP protocol"?
This could be due to the service endpoint binding not using the HTTP protocol

SymbolFinder.FindReferencesAsync doesn't find anything

I want to find all PropertyChangedEventHandler events in my solution, and then find all listeners added to those events. But I can't seem to get a list of the events.
This is all the code in the solution being analyzed:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace RoslynTarget
{
public class Example : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged = delegate { };
public void DoNothing() { }
}
}
And this is my code for analyzing it. references.Count == 1 and r.Locations.Count == 0, but exactly one location should be found. What's going on here?
Program.cs
using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using Microsoft.CodeAnalysis.FindSymbols;
using Microsoft.CodeAnalysis.MSBuild;
namespace RoslynTest
{
class Program
{
static void Main(string[] args)
{
const string solutionPath = #"C:\Users\<user>\Code\RoslynTarget\RoslynTarget.sln";
const string projectName = "RoslynTarget";
var msWorkspace = MSBuildWorkspace.Create(new Dictionary<string, string> { { "CheckForSystemRuntimeDependency", "true" } });
var solution = msWorkspace.OpenSolutionAsync(solutionPath).Result;
var project =
solution.Projects
.Where(proj => proj.Name == projectName)
.First();
var compilation = project.GetCompilationAsync().Result;
var eventType = compilation.ResolveType("System.ComponentModel.PropertyChangedEventHandler").First();
var references = SymbolFinder.FindReferencesAsync(eventType, solution).Result;
foreach (var r in references)
{
foreach (var loc in r.Locations)
{
// ...
}
}
}
}
}
Extensions.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis;
namespace RoslynTest
{
public static class Extensions
{
public static IEnumerable<INamedTypeSymbol> ResolveType(this Compilation compilation, string classFullName)
{
return new IAssemblySymbol[] { compilation.Assembly }
.Concat(compilation.References
.Select(compilation.GetAssemblyOrModuleSymbol)
.OfType<IAssemblySymbol>())
.Select(asm => asm.GetTypeByMetadataName(classFullName))
.Where(cls => cls != null);
}
}
}

Recently I've done similar thing where I was trying to find the reference of a method in complete solution.
To use FindReferenceAsync you have create symantic model first and find the symbol from there. Once you have the symbol you can use the FindReferenceAsync.
Here's the snippet that I used and it's working:
var solution = msWorkspace.OpenSolutionAsync(solutionPath).Result;
foreach (var project in solution.Projects)
{
foreach (var document in project.Documents)
{
var model = document.GetSemanticModelAsync().Result;
var methodInvocation = document.GetSyntaxRootAsync().Result;
InvocationExpressionSyntax node = null;
try
{
node = methodInvocation.DescendantNodes().OfType<InvocationExpressionSyntax>()
.Where(x => ((MemberAccessExpressionSyntax)x.Expression).Name.ToString() == methodName).FirstOrDefault();
if (node == null)
continue;
}
catch(Exception exception)
{
// Swallow the exception of type cast.
// Could be avoided by a better filtering on above linq.
continue;
}
methodSymbol = model.GetSymbolInfo(node).Symbol;
found = true;
break;
}
if (found) break;
}
foreach (var item in SymbolFinder.FindReferencesAsync(methodSymbol, solution).Result)
{
foreach (var location in item.Locations)
{
Console.ForegroundColor = ConsoleColor.Green;
Console.WriteLine("Project Assembly -> {0}", location.Document.Project.AssemblyName);
Console.ResetColor();
}
}
Here's the complete working code. If you want to visualize the Roslyn tree then you can try using Roslyn tree visualizer to see code structuring.
Update
As per discussion in comments with OP Installing Roslyn SDK fixed the issue. Assuming that there might be some updates in SDK to generate Symbols information as compared to Nuget dlls when using GetCompilationAsync.

WCF process-is-terminated-due-to-stackoverflowexception

when i run a method within my WCF service i get "An unhandled exception of type 'System.StackOverflowException' occurred in developer1SVC.dll".
No infinite loops exist and no infinite recursion is occurring. Any ideas to why this may be happening? when i run the method through wcf test client. I get the results back correctly however, hooking it up to my console app and running it breaks the application. The other methods run fine. It is this one method. Just trying to get the feel for WCF services. The service breaks right after i return accounts from the "generateMultiplAccounts" method.
Much help appreciated.
Service
using developer1.Core.ServiceContracts;
using developer1.Core.Data;
using developer1.Core.Dto;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.ServiceModel.Web;
using System.Text;
using developer1.Core.Dto.Account;
namespace developer1.Core.Service
{
// NOTE: You can use the "Rename" command on the "Refactor" menu to change the class name "Service1" in code, svc and config file together.
// NOTE: In order to launch WCF Test Client for testing this service, please select Service1.svc or Service1.svc.cs at the Solution Explorer and start debugging.
public class Service1 : IService1
{
public string GetData(int value)
{
return string.Format("You entered: {0}", value);
}
public CompositeType GetDataUsingDataContract(CompositeType composite)
{
if (composite == null)
{
throw new ArgumentNullException("composite");
}
if (composite.BoolValue)
{
composite.StringValue += "Suffix";
}
Console.WriteLine(composite.StringValue + composite.BoolValue);
return composite;
}
public List<AccountDto> GenerateMultipleAccounts(int count)
{
List<AccountDto> accounts = new List<AccountDto>();
for (int i = 0; i < count; i++)
{
AccountDto newAccount = new AccountDto() { AccountId = Guid.NewGuid()};
accounts.Add(newAccount);
}
return accounts;
}
}
}
Console Application
using developer1.Core;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using developer1.Core.Service;
using developer1.Core.Dto.Account;
using developer1.Core.ServiceContracts;
using AccountServiceClient = developer1.TestConsole.ServiceReference1.Service1Client;
namespace developer1.TestConsole
{
class Program
{
static void Main(string[] args)
{
try
{
AccountServiceClient AccountServiceClient = new AccountServiceClient();
Guid testGuid = Guid.NewGuid();
List<AccountDto> newAccounts = new List<AccountDto>(AccountServiceClient.GenerateMultipleAccounts(2));
Console.WriteLine(testGuid);
CompositeType testDataContract = new CompositeType() { StringValue = "test", BoolValue = true };
testDataContract = AccountServiceClient.GetDataUsingDataContract(testDataContract);
Console.WriteLine(AccountServiceClient.GetData(6));
Console.WriteLine(testDataContract.StringValue);
//foreach (var item in newAccounts)
//{
// Console.WriteLine(item.AccountId);
//}
}
catch(Exception e) {
Console.WriteLine(e);
}
Console.Read();
}
}
}
Data Contract
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.Web;
namespace developer1.Core.Dto.Account
{
[DataContract]
public class AccountDto
{
[DataMember]
public Guid AccountId { get; set; }
//get { return this.AccountId; }
//set { this.AccountId = this.AccountId == Guid.Empty ? Guid.NewGuid() : value; }
[DataMember]
public Guid UserId { get; set; }
[DataMember]
public string AccountName { get; set; }
[DataMember]
public string BankName { get; set; }
//get { return this.BankName; }
//set { this.BankName = this.BankName == null ? "Unspecified" : value; }
}
}
ANSWER!!!!!!!
So I have solved this dreaded issue. You must create a WCF Service Library instead of a WCF Service Application. My god that is stupid that the application wont let you split your components outside of the interface.

Web service unhandled exception

To use webservice I added a web service reference and then added the following code to my MainPage.xaml.cs file.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;
namespace WebServiceTest
{
public partial class MainPage : PhoneApplicationPage
{
// Constructor
public MainPage()
{
InitializeComponent();
}
private void PhoneApplicationPage_Loaded(object sender, RoutedEventArgs e)
{
try
{
ServiceReference.PDAServiceSoapClient ws =
new ServiceReference.PDAServiceSoapClient();
ws.GetResoureAroudCompleted +=
new EventHandler<ServiceReference.GetResoureAroudCompletedEventArgs>(ws_GetResoureAroudCompleted);
ws.GetResoureAroudAsync("基站,机楼", 113, 23, 10000);
}
catch
{
System.Windows.MessageBox.Show("error！");
}
}
void ws_GetResoureAroudCompleted(object sender, ServiceReference.GetResoureAroudCompletedEventArgs e)
{
if (e.Error != null)
{
var result = e.Result;
}
}
}
}
Then I ran PhoneApplication and got this exception:
System.InvalidOperationException was unhandled
Message=There was an error reflecting type 'WebServiceTest.ServiceReference.GetResoureAroudResponseGetResoureAroudResult'.
InnerException: System.InvalidOperationException
Message=There was an error reflecting property 'Any1'.
in Reference.cs
Code:
public WebServiceTest.ServiceReference.GetResoureAroudResponseGetResoureAroudResult EndGetResoureAroud(System.IAsyncResult result) {
object[] _args = new object[0];
**WebServiceTest.ServiceReference.GetResoureAroudResponseGetResoureAroudResult _result = ((WebServiceTest.ServiceReference.GetResoureAroudResponseGetResoureAroudResult)(base.EndInvoke("GetResoureAroud", _args, result)));**
return _result;
}
It's not caught by try-catch, anybody know why?

I have faced the same problem and after investigating I did the following which solved the issue:
usually you will find two properties in the class causing the error:
private System.Xml.Linq.XElement[] anyField;
private System.Xml.Linq.XElement any1Field;
What I did was the following:
1- change the first property from an array to a single value variable as follows
private System.Xml.Linq.XElement anyField;
2- change the getter and setter methods of this property , to match your changes
[System.Xml.Serialization.XmlAnyElementAttribute(Namespace="http://www.w3.org/2001/XMLSchema", Order=0)]
public System.Xml.Linq.XElement Any {
get {
return this.anyField;
}
set {
this.anyField = value;
this.RaisePropertyChanged("Any");
}
}
3- remove or comment out the second property
// private System.Xml.Linq.XElement any1Field;
4- remove or comment out the second property's getter and setter methods
/*
[System.Xml.Serialization.XmlAnyElementAttribute(Namespace="urn:schemas-microsoft-com:xml-diffgram-v1", Order=1)]
public System.Xml.Linq.XElement Any1 {
get {
return this.any1Field;
}
set {
this.any1Field = value;
this.RaisePropertyChanged("Any1");
}
}
*/
At this point you can now access the resulting XML as follows by calling the "Any" property which will return an xml which you can manipulate :
ex, in my case it was the following class causing the problems
public partial class GetUserBalancesClassAccounts
in my method I was able to access the xml as follows
GetUserBalancesClassAccounts accts = balances.Accounts;
XElement doc = accts.Any;
foreach( XElement docElement in doc.Elements()){
foreach (XElement account in docElement.Elements("Account"))
{
... do something ...
}
}

The exception is not caught by your exception handler because it occurs in the framework and is out of scope. Depending on whether the webservice conforms to best practice, it may surface an Error object and if so you should inspect this prior to attempting to retrieve any data.
This can produce symptoms similar to yours, but I'm not certain this is the problem you face.

Cascade Saves with Fluent NHibernate AutoMapping - Old Answer Still Valid?

I want to do exactly what this question asks:
Cascade Saves with Fluent NHibernate AutoMapping
Using Fluent Nhibernate Mappings to turn on "cascade" globally once for all classes and relation types using one call rather than setting it for each mapping individually.
The answer to the earlier question looks great, but I'm afraid that the Fluent Nhibernate API altered its .WithConvention syntax last year and broke the answer... either that or I'm missing something.
I keep getting a bunch of name space not found errors relating to the IOneToOnePart, IManyToOnePart and all their variations:
"The type or namespace name 'IOneToOnePart' could not be found (are you missing a using directive or an assembly reference?)"
I've tried the official example dll's, the RTM dll's and the latest build and none of them seem to make VS 2008 see the required namespace.
The second problem is that I want to use the class with my AutoPersistenceModel
but I'm not sure where to this line:
.ConventionDiscovery.AddFromAssemblyOf()
in my factory creation method.
private static ISessionFactory CreateSessionFactory()
{
return Fluently.Configure()
.Database(SQLiteConfiguration.Standard.UsingFile(DbFile))
.Mappings(m => m.AutoMappings
.Add(AutoMap.AssemblyOf<Shelf>(type => type.Namespace.EndsWith("Entities"))
.Override<Shelf>(map =>
{
map.HasManyToMany(x => x.Products).Cascade.All();
})
)
)//emd mappings
.ExposeConfiguration(BuildSchema)
.BuildSessionFactory();//finalizes the whole thing to send back.
}
Below is the class and using statements I'm trying
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using FluentNHibernate.Conventions;
using FluentNHibernate.Cfg;
using FluentNHibernate.Cfg.Db;
using NHibernate;
using NHibernate.Cfg;
using NHibernate.Tool.hbm2ddl;
using FluentNHibernate.Mapping;
namespace TestCode
{
public class CascadeAll : IHasOneConvention, IHasManyConvention, IReferenceConvention
{
public bool Accept(IOneToOnePart target)
{
return true;
}
public void Apply(IOneToOnePart target)
{
target.Cascade.All();
}
public bool Accept(IOneToManyPart target)
{
return true;
}
public void Apply(IOneToManyPart target)
{
target.Cascade.All();
}
public bool Accept(IManyToOnePart target)
{
return true;
}
public void Apply(IManyToOnePart target)
{
target.Cascade.All();
}
}
}

The easiest way I've found to do this for a whole project is to use DefaultCascade:
.Conventions.Add( DefaultCascade.All() );
Go to "The Simplest Conventions" section on the wiki, for this, and a list of others.
Edit:
Here's the list from the Wiki:
Table.Is(x => x.EntityType.Name + "Table")
PrimaryKey.Name.Is(x => "ID")
AutoImport.Never()
DefaultAccess.Field()
DefaultCascade.All()
DefaultLazy.Always()
DynamicInsert.AlwaysTrue()
DynamicUpdate.AlwaysTrue()
OptimisticLock.Is(x => x.Dirty())
Cache.Is(x => x.AsReadOnly())
ForeignKey.EndsWith("ID")
A word of warning - some of the method names in the Wiki may be wrong. I edited the Wiki with what I could verify (i.e. DefaultCascade and DefaultLazy), but can't vouch for the rest. But you should be able to figure out the proper names with Intellisense if the need arises.

Here's a full working example similar to the Getting Started guide https://github.com/jagregory/fluent-nhibernate/wiki/Getting-started
//=====CONSOLE MAIN
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using FluentNHibernate.Cfg;
using FluentNHibernate.Cfg.Db;
using NHibernate;
using NHibernate.Cfg;
using NHibernate.Tool.hbm2ddl;
using System.IO;
using FluentNHibernate.Automapping;
using App4.Entities;
using System.Diagnostics;
namespace App4
{
class Program
{
static void Main(string[] args)
{
// create our NHibernate session factory
var sessionFactory = CreateSessionFactory();
using (var session = sessionFactory.OpenSession())
{
// populate the database
using (var transaction = session.BeginTransaction())
{
// create a couple of Stores each with some Products and Employees
var topShelf = new Shelf();
var sw = new Stopwatch();
sw.Start();
for (var i = 0; i < 1000; i++)
{
var potatoes = new Product { Name = "Potatoes" + i.ToString(), Price = 3.60 + i };
var meat = new Product { Name = "Meat" + i.ToString(), Price = 4.49 + i };
//session.SaveOrUpdate(potatoes); //===<<cascading save handles this :-)
//session.SaveOrUpdate(meat);
topShelf.Products.Add(meat);
topShelf.Products.Add(potatoes);
}
sw.Stop();
session.SaveOrUpdate(topShelf);
//session.SaveOrUpdate(superMart);
transaction.Commit();
Console.WriteLine("Add Items: " + sw.ElapsedMilliseconds);
}
}
using (var session = sessionFactory.OpenSession())
{
// retreive all stores and display them
using (session.BeginTransaction())
{
var shelves = session.CreateCriteria(typeof(Shelf)).List<Shelf>();
foreach (var store in shelves)
{
WriteShelfPretty(store);
}
}
}
Console.ReadLine();
}
private const string DbFile = "FIVEProgram.db";
private static ISessionFactory CreateSessionFactory()
{
return Fluently.Configure()
.Database(SQLiteConfiguration.Standard.UsingFile(DbFile))
.Mappings(m => m.AutoMappings
.Add(AutoMap.AssemblyOf<Shelf>(type => type.Namespace.EndsWith("Entities"))
.Override<Shelf>(map =>
{
map.HasManyToMany(x => x.Products);//.Cascade.All();
})
.Conventions.AddFromAssemblyOf<CascadeAll>()
)
) //emd mappings
.ExposeConfiguration(BuildSchema)//Delete and remake db (see function below)
.BuildSessionFactory();//finalizes the whole thing to send back.
}
private static void BuildSchema(Configuration config)
{
// delete the existing db on each run
if (File.Exists(DbFile))
File.Delete(DbFile);
// this NHibernate tool takes a configuration (with mapping info in)
// and exports a database schema from it
new SchemaExport(config)
.Create(false, true);
}
private static void WriteShelfPretty(Shelf shelf)
{
Console.WriteLine(shelf.Id);
Console.WriteLine(" Products:");
foreach (var product in shelf.Products)
{
Console.WriteLine(" " + product.Name);
}
Console.WriteLine();
}
}
}
//Data Classes
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace App4.Entities
{
public class Product
{
public virtual int Id { get; private set; }
public virtual string Name { get; set; }
public virtual double Price { get; set; }
}
public class Shelf
{
public virtual int Id { get; private set; }
public virtual IList<Product> Products { get; private set; }
public Shelf()
{
Products = new List<Product>();
}
}
}
//Cascade All Helper Class
using FluentNHibernate.Conventions;
using FluentNHibernate.Conventions.AcceptanceCriteria;
using FluentNHibernate.Conventions.Inspections;
using FluentNHibernate.Conventions.Instances;
using System;
using System.Collections.Generic;
namespace App4
{
public class CascadeAll :
IHasOneConvention, //Actually Apply the convention
IHasManyConvention,
IReferenceConvention,
IHasManyToManyConvention,
IHasOneConventionAcceptance, //Test to see if we should use the convention
IHasManyConventionAcceptance, //I think we could skip these since it will always be true
IReferenceConventionAcceptance, //adding them for reference later
IHasManyToManyConventionAcceptance
{
//One to One
public void Accept(IAcceptanceCriteria<IOneToOneInspector> criteria)
{
//criteria.Expect(x => (true));
}
public void Apply(IOneToOneInstance instance)
{
instance.Cascade.All();
}
//One to Many
public void Accept(IAcceptanceCriteria<IOneToManyCollectionInspector> criteria)
{
//criteria.Expect(x => (true));
}
public void Apply(IOneToManyCollectionInstance instance)
{
instance.Cascade.All();
}
//Many to One
public void Accept(IAcceptanceCriteria<IManyToOneInspector> criteria)
{
// criteria.Expect(x => (true));
}
public void Apply(IManyToOneInstance instance)
{
instance.Cascade.All();
}
//Many to Many
public void Accept(IAcceptanceCriteria<IManyToManyCollectionInspector> criteria)
{
// criteria.Expect(x => (true));
}
public void Apply(IManyToManyCollectionInstance instance)
{
instance.Cascade.All();
}
}
}

The signature for the conventions has changed. Are you not using something like ReSharper? That would point you to that conclusion.
You can read more about the new conventions on the wiki.