Using PostSharp I would like to do Encryption/Decryption on Field Interception
I have a Class
public class guestbookentry
{
[Encryption] // This Attribute has to Encrypt and Decrypt
public string Message { get; set; }
public string GuestName { get; set; }
}
I am saving the object in Azure Tables. Only particular Field has to be get En/Decrypt.
PostSharp Attribute on Field Interception
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using PostSharp;
using PostSharp.Aspects;
using EncryptionDecryption;
using PostSharp.Serialization;
using PostSharp.Aspects.Advices;
using PostSharp.Extensibility;
namespace GuestBook_Data
{
[Serializable]
public class EncryptionAttribute : LocationInterceptionAspect
{
[MulticastPointcut(Targets = MulticastTargets.Field, Attributes = MulticastAttributes.Instance)]
public override void OnSetValue(LocationInterceptionArgs args)
{
base.OnSetValue(args);
if (args.Value != null)
{
MD5CryptoServiceExample objMD5Encrypt = new MD5CryptoServiceExample();
args.Value = objMD5Encrypt.Encrypt(args.Value.ToString()).Replace(" ", "+");
args.ProceedSetValue();
}
}
public override void OnGetValue(LocationInterceptionArgs args)
{
base.OnGetValue(args);
if (args.Value != null)
{
MD5CryptoServiceExample objMD5Encrypt = new MD5CryptoServiceExample();
args.Value = objMD5Encrypt.Decrypt(args.Value.ToString()); //objMD5Encrypt.Decrypt(args.Value.ToString());
args.ProceedGetValue();
}
}
}
}
Problem is
1. Successive Encryption and Decryption happens which is difficult to handle.
Kindly suggest
Note, that calling base.OnSetValue(args) is the same as calling args.ProceedSetValue(), and calling base.OnGetValue(args) is the same as calling args.ProceedGetValue(). This means that you're calling the proceed methods twice in each of your handlers.
What you need to do is to call args.ProceedGetValue() at the start of the OnGetValue to read the encrypted value, and call args.ProceedSetValue() at the end of the OnSetValue to save the encrypted value.
public override void OnGetValue(LocationInterceptionArgs args)
{
args.ProceedGetValue();
if (args.Value != null)
{
args.Value = // decrypt
}
}
public override void OnSetValue(LocationInterceptionArgs args)
{
if (args.Value != null)
{
args.Value = // encrypt
}
args.ProceedSetValue();
}
Also, you don't need to apply the [MulticastPointcut] attribute. It's used when developing composite aspects as described in Developing Composite Aspects.
Related
I´m migratting a xamarin forms 3.x app with Prism to forms 4 with shell navigation.
Do I have to create my custom solution to pass complex parameters to the new page or Xamarin has some buildin feature to receive other than string parameters?
Thanks.
As far as I know, and, reading the docs, the only samples regard passing simple data, like string when navigating.
However, I was able to find an Issue (and Pull Request), for passing objects/ Models, for the next version (I assume this is the case you are referring to).
You can track it here.
I've run some tests which seems to be working. I'm relatively new to Xamarin, hence recommend caution and welcome any feedback for any potential issues I may be overlooking.
I wrote an extension to Shell to accept a data object parameter 'navigationData' as follows:-
await Shell.Current.GoToAsync(state, navigationData, animate);
The extension ...
namespace Xamarin.Forms
{
public static class ShellExtensions
{
public static async Task GoToAsync(this Shell shell, ShellNavigationState state, object navigationData, bool animate=false)
{
shell.Navigated += async (sender, e) =>
{
if ((Shell.Current?.CurrentItem?.CurrentItem as IShellSectionController)?.PresentedPage is MyContentPage
p) await p.InitializeAsync(navigationData).ConfigureAwait(false);
};
await shell.GoToAsync(state, animate);
}
}
}
As shown above the extension:-
hooks to the Shell 'Navigated' event,
retrieves the 'current view (page)' as 'MyContentPage' i.e. subclassed ContentPage,
calls an InitializeAsync method on the view passing in the
navigationData parameter
the view then calls an InitializeAsync
method on the binding context (view model) passing the
navigationData parameter onto the viewModel.
In the extension method above, 'MyContentPage' is a custom abstract subclass of ContentPage with an InitializeAsync(navigationData) method that simply calls a similar method on the viewModel (binding context of the view).
Similarily, ViewModels subclass a custom ViewModelBase class that has a virtual InitializeAsync(navigationData). This can be overridden in the viewModel with the desired implementation and handling of the navigation data.
Simplified sample of Views, ViewModels and related base classes shown below
using System.Threading.Tasks;
using MyXamarinApp.ViewModels;
using Xamarin.Forms;
namespace MyXamarinApp.Views
{
public ItemDetailPage : MyContent<ItemDetailViewModel>{}
public ItemPage : MyContentPage<ItemViewModel>{}
public abstract class MyContentPage<T> : MyContentPage where T : ViewModelBase
{
protected T Vm;
protected override ViewModelBase VmBase => Vm as ViewModelBase;
protected MyContentPage()
{
BindingContext = Vm = ViewModelLocator.Resolve<T>();
}
private Comand _showDetailCommand;
public Command ShowDetailCommand
{
get { return _showDetailCommand ??= new Command(async () =>
await Shell.Current.GoToAsync("itemDetail", new NavigationDataObject())); }
}
}
public abstract class MyContentPage : ContentPage
{
protected abstract ViewModelBase VmBase { get; }
public virtual async Task InitializeAsync(object navigationData)
{
await VmBase.InitializeAsync(navigationData);
}
}
}
public class NavigationDataObject
{
'Properties' etc.
}
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq.Expressions;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Threading.Tasks;
namespace MyXamarinApp.ViewModels
{
public ItemViewModel : ViewModelBase{}
public ItemDetailViewModel : ViewModelBase
{
private NavigationDataObject _navData;
public override async Task InitializeAsync(object navigationData)
{
if (navigationData is NavigationDataObject navData)
{
_navData = navData;
}
await base.InitializeAsync(navigationData);
}
}
public abstract class ViewModelBase
{
public virtual Task InitializeAsync(object navigationData)
{
return Task.FromResult(false);
}
}
}
You can always serialize the model to a JSON string and un-serializes it on the other side?
async void Handle_ItemTapped(object sender, ItemTappedEventArgs e)
{
if (e.Item == null)
return;
DailyPnL PnLClicked = (DailyPnL)e.Item;
string jason = await Task.Run(() => JsonConvert.SerializeObject(PnLClicked));
await Shell.Current.GoToAsync($"viewdailypnl?pnlmodel={jason}");
//Deselect Item
((ListView)sender).SelectedItem = null;
}
Then in your code behind:
public string pnlmodel
{
set
{
string derulo = Uri.UnescapeDataString(value);
viewModel.PnL = Task.Run(() => JsonConvert.DeserializeObject<DailyPnL>(derulo)).Result;
}
}
There is a framework called Xamarin.Zero https://github.com/markjackmilian/Xam.Zero
It lets you use shell while giving you convenient ViewModel to ViewModel navigation, IOC.
You can user stored preferences to store complex data like:
private async void OnItemSelected(Item item)
{
if (item == null)
return;
var jsonstr = JsonConvert.SerializeObject(item);
//Clear the shared preferences in case there is any
Preferences.Clear();
//Store your complex json on a shared preference
Preferences.Set("Data", jsonstr);
await Shell.Current.GoToAsync(nameof(DetailsPage));
}
Retrieve it on the details page like:
bool hasKey = Preferences.ContainsKey("Data");
var content = Preferences.Get("Data", string.Empty);
Details details = hasKey ? JsonConvert.DeserializeObject<Model>(content) : null;
Using AutoFixture with the AutoFixture.AutoMoq package, I sometimes find tests that weren't configured to correctly test the thing they meant to test, but the problem was never discovered because of the default (Loose) Mock behavior:
public interface IService
{
bool IsSomethingTrue(int id);
}
void Main()
{
var fixture = new Fixture()
.Customize(new AutoMoqCustomization());
var service = fixture.Freeze<Mock<IService>>();
Console.WriteLine(service.Object.IsSomethingTrue(1)); // false
}
I'd like to make Mocks get created with Strict behavior, so we're forced to call Setup() for the methods we expect to be called. I can do this for each individual mock like this:
fixture.Customize<Mock<IService>>(c => c.FromFactory(() => new Mock<IService>(MockBehavior.Strict)));
But after combing through source code for AutoMoqCustomization() and the various ISpecimenBuilder and other implementations, I'm pretty lost as to the best way to just make all Mocks get initialized with strict behavior. The framework appears to be very flexible and extensible, so I'm sure there's a simple way to do this--I just can't figure out how.
There's no simple built-in feature that will enable you to do something like that, but it shouldn't be that hard to do.
Essentially, you'd need to change MockConstructorQuery so that it invokes the constructor that takes a MockBehavior value, and pass in MockBehavior.Strict.
Now, you can't change that behaviour in MockConstructorQuery, but that class is only some 9-10 lines of code, so you should be able to create a new class that implements IMethodQuery by using MockConstructorQuery as a starting point.
Likewise, you'll also need to create a custom ICustomization that does almost exactly the same as AutoMoqCustomization, with the only exception that it uses your custom IMethodQuery with strict mock configuration instead of MockConstructorQuery. That's another 7 lines of code you'll need to write.
All that said, in my experience, using strict mocks is a bad idea. It'll make your tests brittle, and you'll waste a lot of time mending 'broken' tests. I can only recommend that you don't do this, but now I've warned you; it's your foot.
For those interested, down below you can find #MarkSeemann's reply translated into code. I am pretty sure it does not cover all use cases and it was not heavily tested. But it should be a good starting point.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Moq;
using Ploeh.AutoFixture;
using Ploeh.AutoFixture.AutoMoq;
using Ploeh.AutoFixture.Kernel;
namespace ConsoleApplication1
{
public class StrictAutoMoqCustomization : ICustomization
{
public StrictAutoMoqCustomization() : this(new MockRelay()) { }
public StrictAutoMoqCustomization(ISpecimenBuilder relay)
{
// TODO Null check params
Relay = relay;
}
public ISpecimenBuilder Relay { get; }
public void Customize(IFixture fixture)
{
// TODO Null check params
fixture.Customizations.Add(new MockPostprocessor(new MethodInvoker(new StrictMockConstructorQuery())));
fixture.ResidueCollectors.Add(Relay);
}
}
public class StrictMockConstructorMethod : IMethod
{
private readonly ConstructorInfo ctor;
private readonly ParameterInfo[] paramInfos;
public StrictMockConstructorMethod(ConstructorInfo ctor, ParameterInfo[] paramInfos)
{
// TODO Null check params
this.ctor = ctor;
this.paramInfos = paramInfos;
}
public IEnumerable<ParameterInfo> Parameters => paramInfos;
public object Invoke(IEnumerable<object> parameters) => ctor.Invoke(parameters?.ToArray() ?? new object[] { });
}
public class StrictMockConstructorQuery : IMethodQuery
{
public IEnumerable<IMethod> SelectMethods(Type type)
{
if (!IsMock(type))
{
return Enumerable.Empty<IMethod>();
}
if (!GetMockedType(type).IsInterface && !IsDelegate(type))
{
return Enumerable.Empty<IMethod>();
}
var ctor = type.GetConstructor(new[] { typeof(MockBehavior) });
return new IMethod[]
{
new StrictMockConstructorMethod(ctor, ctor.GetParameters())
};
}
private static bool IsMock(Type type)
{
return type != null && type.IsGenericType && typeof(Mock<>).IsAssignableFrom(type.GetGenericTypeDefinition()) && !GetMockedType(type).IsGenericParameter;
}
private static Type GetMockedType(Type type)
{
return type.GetGenericArguments().Single();
}
internal static bool IsDelegate(Type type)
{
return typeof(MulticastDelegate).IsAssignableFrom(type.BaseType);
}
}
}
Usage
var fixture = new Fixture().Customize(new StrictAutoMoqCustomization());
I am looking at implementing a logging mechanism in a site of mine, I wish to do basic user action logging. I don't want to log every single button they click on, but I do want to log actions they do which makes changes.
Are there any libraries or articles / tutorials out there which can help me implement a good and efficient logging mechanism for my asp.net site. Im not sure if there are any changes in MVC5 that might come in use for logging as I know user Authentication and Authorization has changed a fair amount from 4 to 5.
I'm sure that there is a dynamic library out there that will work in many different situations.
Nice to haves:
Async capability
Scalable
Simple to use
I'm thinking along the lines of creating a custom filter or attribute that then logs the suers action, but that's just my Idea, Im here to ask what the standard / industry way to do it is.
There isn't an industry standard.
I've used filters or I've overridden the "onActionExecuting" method on the base controller class to record controller / action events.
EDIT ::
Trying to be more helpful but this is really vague.
If you're worried about errors and things like that use elmah.
For other logging use Nlog or Log4Net.
If you're trying to do extra logging like auditing or something like that you can use any combination of those, or something custom. In my site I created a table that stores every click on the site by creating an object sort of like this :
public class audit
{
public int ID { get; set; }
public DateTime AuditDate { get; set; }
public string ControllerName { get; set; }
public string ActionName { get; set; }
public Dictionary<string, object> values
}
In my base constructor, I overrode the OnActionExecuting event :
protected override void OnActionExecuting(ActionExecutingContext ctx)
{
checkForLogging(ctx);
//do not omit this line
base.OnActionExecuting(ctx);
}
Lets say I want to log all Get Requests using my new audit object
private void checkForLogging(ActionExecutingContext ctx)
{
//we leave logging of posts up to the actual methods because they're more complex...
if (ctx.HttpContext.Request.RequestType == "GET")
{
logging(ctx.ActionDescriptor.ActionName, ctx.ActionDescriptor.ControllerDescriptor.ControllerName, ctx.ActionParameters);
}
}
Thats all the info I need to fill my logging object with the action name, the controller name and all the params passed into the method. You can either save this to a db, or a logfile or whatever you want really.
The point is just its a pretty big thing. This is just one way to do it and it may or may not help you. Maybe define a bit more what exactly you want to log and when you want to do it?
You can create a custom attribute and decorate methods with it and then check if that attribute is present when the OnActionExecuting method fires. You can then get that filter if present and read from it and use that to drive your logging if you want...
Maybe this example will help.
My focus on logging is in the CREATE, EDIT, DELETE actions.
I am using MVC 5 Code-first EF 6.1 (VS 2013) ,
and for this example I are referring to the Create action for an entity called "WorkFlow"
I actually view these logs from SSRS, but you could add a controller and Views for WriteUsageLog and view them from the MVC application
MODEL: Create a MODEL Entity called "WriteUsageLog" which will be where the log records are kept
CONTROLLER: Extract, or refactor, the HttpPost overload of the "Create" action from the WorkFlowController into a Partial Class called "WorkFlowController" (These partials are to avoid being deleted and rebuilt when I use the wizard to create Controllers)
Other Classes in the CONTROLLER folder: Then there are some helper functions that are required in a class called "General_Object_Extensions" and "General_ActiveDirectory_Extensions" (NOTE: these are not really 'extensions')
Add the following line to the DBContext:
public DbSet WriteUsageLogs { get; set; }
The advantage of this example is:
I am recording the following for the record:
User Name from Active Directory
The DateTime that the log record is being created
The computer name
And a Note that consists of the values for all the entity properties
I am recording the log in a table from which I can access it either using an MVC controller, or preferably from SQL Server Report Server. Where I can monitor all my MVC applications
/Models/WriteUsageLog.cs
using System;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
namespace MileageReimbursement.Models
{
public class WriteUsageLog
{
public WriteUsageLog()
{
this.DateTimeCreated = DateTime.Now; // auto-populates DateTimeCreated field
}
[Key]
public int WriteUsageLogID { get; set; }
[Column(TypeName = "nvarchar(max)")]
public string Note { get; set; }
public string UserLogIn { get; set; }
public string ComputerName { get; set; }
public DateTime DateTimeCreated { get; private set; } //private set to for auto-populates DateTimeCreated field
}
}
/Controllers/ControllerPartials.cs
using System.Linq;
using System.Web.Mvc;
using MileageReimbursement.Models;
//These partials are to avoid be deleted and rebuilt when I use the wizard to create Controllers
namespace MileageReimbursement.Controllers
{
public partial class WorkFlowController : Controller
{
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Create([Bind(Include = "whatever")] WorkFlow workFlow)
{
...
if (ModelState.IsValid)
{
db.WorkFlows.Add(workFlow);
db.SaveChanges();
//===================================================================================================================
string sX = workFlow.GetStringWith_RecordProperties();
//===================================================================================================================
var logRecord = new WriteUsageLog();
logRecord.Note = "New WorkFlow Record Added - " + sX;
logRecord.UserLogIn = General_ActiveDirectory_Extensions.fn_sUser();
string IP = Request.UserHostName;
logRecord.ComputerName = General_functions.fn_ComputerName(IP);
db.WriteUsageLogs.Add(logRecord);
db.SaveChanges();
//===================================================================================================================
return RedirectToAction("Index");
}
else // OR the user is directed back to the validation error messages and given an opportunity to correct them
{
...
return View(workFlow); //This sends the user back to the CREATE view to deal with their errors
}
}
}
}
/Controllers/ControllerExtensions.cs
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.DirectoryServices.AccountManagement;
using System.Linq;
using System.Net;
using System.Net.Mail;
using System.Reflection;
using System.Security.Cryptography;
using System.Text;
using System.Web;
namespace MileageReimbursement.Controllers
{
public static class General_ActiveDirectory_Extensions
{
public static string fn_sUser()
{
char cX = '\\';
string sUser = General_functions.fn_ReturnPortionOfStringAfterLastOccuranceOfACharacter(HttpContext.Current.User.Identity.Name, cX);
return sUser; //returns just the short logon name Example for 'accessiicarewnc\ggarson', it returns 'ggarson'
}
} //General_ActiveDirectory_Extensions
public static class General_Object_Extensions
{
public static string GetStringWith_RecordProperties(this object Record)
{
string sX = null;
Dictionary<string, object> _record = GetDictionary_WithPropertiesForOneRecord(Record);
int iPropertyCounter = 0;
foreach (var KeyValuePair in _record)
{
iPropertyCounter += 1;
object thePropertyValue = _record[KeyValuePair.Key];
if (thePropertyValue != null)
{
sX = sX + iPropertyCounter + ") Property: {" + KeyValuePair.Key + "} = [" + thePropertyValue + "] \r\n";
}
else
{
sX = sX + iPropertyCounter + ") Property: {" + KeyValuePair.Key + "} = [{NULL}] \r\n";
}
}
return sX;
}
public static Dictionary<string, object> GetDictionary_WithPropertiesForOneRecord(object atype)
{
if (atype == null) return new Dictionary<string, object>();
Type t = atype.GetType();
PropertyInfo[] props = t.GetProperties();
Dictionary<string, object> dict = new Dictionary<string, object>();
foreach (PropertyInfo prp in props)
{
object value = prp.GetValue(atype, new object[] { });
dict.Add(prp.Name, value);
}
return dict;
}
} //General_Object_Extensions
public static class General_functions
{
public static string fn_ComputerName(string IP)
{
//USAGE
//From: http://stackoverflow.com/questions/1444592/determine-clients-computer-name
//string IP = Request.UserHostName;
//string compName = CompNameHelper.DetermineCompName(IP);
IPAddress myIP = IPAddress.Parse(IP);
IPHostEntry GetIPHost = Dns.GetHostEntry(myIP);
List<string> compName = GetIPHost.HostName.ToString().Split('.').ToList();
return compName.First();
}
static public string fn_ReturnPortionOfStringAfterLastOccuranceOfACharacter(string strInput, char cBreakCharacter)
{
// NOTE: for path backslash "/", set cBreakCharacter = '\\'
string strX = null;
//1] how long is the string
int iStrLenth = strInput.Length;
//2] How far from the end does the last occurance of the character occur
int iLenthFromTheLeftOfTheLastOccurance = strInput.LastIndexOf(cBreakCharacter);
int iLenthFromTheRightToUse = 0;
iLenthFromTheRightToUse = iStrLenth - iLenthFromTheLeftOfTheLastOccurance;
//3] Get the Portion of the string, that occurs after the last occurance of the character
strX = fn_ReturnLastXLettersOfString(iLenthFromTheRightToUse, strInput);
return strX;
}
static private string fn_ReturnLastXLettersOfString(int iNoOfCharToReturn, string strIn)
{
int iLenth = 0;
string strX = null;
int iNoOfCharacters = iNoOfCharToReturn;
iLenth = strIn.Length;
if (iLenth >= iNoOfCharacters)
{
strX = strIn.Substring(iLenth - iNoOfCharacters + 1);
}
else
{
strX = strIn;
}
return strX;
}
} //General_functions
}
I would agree that Log4Net and NLog seem to be the two most commonly used products on the different projects I have been a member.
If you are looking for a great tool that you can use for logging, error handling and anything else where AOP would be beneficial I would highly recommend PostSharp (http://www.postsharp.net/). You set your logging/error handling up centrally and then just decorate methods. It is a well documented and supported product. They have a community license, which is free - and it is free for individuals. They also have professional and ultimate versions of the products, which would make more sense if you're using it as a team.
I don't work at PostSharp :-) I've just used it in the past and really like it.
I'm trying build out our logging framework using EntLib Logging and use attribute to indicate which class/method should be logged. So I think Interception would be a good choice. I'm a super noob to Ninject and Interception and I's following the tutorial at Innovatian Software on how to use interception via attributes. But when I run the app, BeforeInvoke and AfterInvoke was never called. Help Please, Thank You!
using System;
using System.Diagnostics;
using System.Collections.Generic;
using Castle.Core;
using Ninject;
using Ninject.Extensions.Interception;
using Ninject.Extensions.Interception.Attributes;
using Ninject.Extensions.Interception.Request;
class Program
{
static void Main(string[] args)
{
var kernel = new StandardKernel();
kernel.Bind<ObjectWithMethodInterceptor>().ToSelf();
var test= kernel.Get<ObjectWithMethodInterceptor>();
test.Foo();
test.Bar();
Console.ReadLine();
}
}
public class TraceLogAttribute : InterceptAttribute
{
public override IInterceptor CreateInterceptor(IProxyRequest request)
{
return request.Context.Kernel.Get<TimingInterceptor>();
}
}
public class TimingInterceptor : SimpleInterceptor
{
readonly Stopwatch _stopwatch = new Stopwatch();
protected override void BeforeInvoke(IInvocation invocation)
{
Console.WriteLine("Before Invoke");
_stopwatch.Start();
}
protected override void AfterInvoke(IInvocation invocation)
{
Console.WriteLine("After Invoke");
_stopwatch.Stop();
string message = string.Format("Execution of {0} took {1}.",
invocation.Request.Method,
_stopwatch.Elapsed);
Console.WriteLine(message);
_stopwatch.Reset();
}
}
public class ObjectWithMethodInterceptor
{
[TraceLog] // intercepted
public virtual void Foo()
{
Console.WriteLine("Foo - User Code");
}
// not intercepted
public virtual void Bar()
{
Console.WriteLine("Bar - User Code");
}
}
I figured it out, I missed the part where I've to disable auto module loading and manually load the DynamicProxy2Module to the kernel. Here's the change to the code:
//var kernel = new StandardKernel(); //Automatic Module Loading doesn't work
var kernel = new StandardKernel(new NinjectSettings() { LoadExtensions = false }, new DynamicProxy2Module());
Hope this help someone else.
I've been reading a lot on TDD over the past few months and decided to jump in and try it out with an easy example, I'm just not sure I'm testing for the right things in practice. Here the tests for a custom Data Annotation for validating emails:
using System;
using System.Text;
using System.Collections.Generic;
using System.Linq;
using Microsoft.VisualStudio.TestTools.UnitTesting;
namespace MembershipTest.Tests
{
[TestClass]
public class CustomDataAnnotationsTest
{
[TestMethod]
public void CustomDataAnnotations_Email_ReturnTrueIfNull()
{
// Arrange
EmailAttribute attribute = new EmailAttribute();
// Act
bool result = attribute.IsValid(null);
// Assert
Assert.AreEqual(true, result);
}
[TestMethod]
public void CustomDataAnnotations_Email_ReturnFalseIfInvalid()
{
// Arrange
EmailAttribute attribute = new EmailAttribute();
// Act
bool result = attribute.IsValid("()[]\\;:,<>#example.com");
// Assert
Assert.AreEqual(false, result);
}
[TestMethod]
public void CustomDataAnnotations_Email_ReturnTrueIfValid()
{
// Arrange
EmailAttribute attribute = new EmailAttribute();
// Act
bool result = attribute.IsValid("john.smith#example.com");
// Assert
Assert.AreEqual(true, result);
}
}
}
And here is the subsequent code written for the test:
using System;
using System.ComponentModel.DataAnnotations;
using System.Net.Mail;
public class EmailAttribute : ValidationAttribute
{
public override bool IsValid(object value)
{
//Let RequiredAttribute validate whether the value is required or not.
if (value == null)
{
return true;
}
//Check to see if System.Net.Mail can send to the address.
try
{
var i = new MailAddress(value.ToString());
}
catch (Exception)
{
return false;
}
return true;
}
}
All tests failed initially and then succeeded after writing the code, but are the tests appropriately written? Too much, or too little? I know this is a very simple example, but I want to make sure I'm on the right track before moving on to more complicated things.
I think you are on the right track. At this point I would suggest some refactoring in your tests. Since you are using
EmailAttribute attribute = new EmailAttribute();
in every test. I would suggest creating TestInitialize() and TestCleanup() methods. The TestInitialize would new EmailAttribute and the TestCleanup would null the object out. This is just a matter of preference. Like this
private EmailAttribute _attribute;
[TestInitialize]
public void TestInitialize()
{
_attribute = new EmailAttribute
}
[TestCleanup]
public void TestCleanup()
{
_attribute = null;
}