asp.net – 测试ControllerFactory(预启动初始化阶段)

有大量关于测试路线设置的帖子/博客(只是谷歌的’mvc测试路线’).这一切都归结为在httpcontext中模拟请求并调用GetRouteData.

如果你真的需要一些忍者技能来模拟buildmanager：有一种方法可以解决内部接口,我用它来进行(LinqPad)实验测试.现在大多数.net程序集都有InternalsVisibleToAttribute集,很可能指向另一个签名的测试程序集.通过扫描目标程序集以获取此属性并在运行中创建与名称(和公钥标记)匹配的程序集,您可以轻松访问内部.

请注意,我个人不会在生产测试代码中使用此技术;但这是隔离一些复杂想法的好方法.

void Main()
{
    var bm = BuildManagerMockBase.CreateMock<MyBuildManager>();
    bm.FileExists("IsCool?").Dump();
}

public class MyBuildManager : BuildManagerMockBase
{
    public override bool FileExists(string virtualPath) { return true; }
}

public abstract class BuildManagerMockBase
{
    public static T CreateMock<T>() 
        where T : BuildManagerMockBase
    {
        // Locate the mvc assembly
        Assembly mvcAssembly = Assembly.GetAssembly(typeof(Controller));

        // Get the type of the buildmanager interface
        var buildManagerInterface = mvcAssembly.GetType("System.Web.Mvc.IBuildManager",true);

        // Locate the "internals visible to" attribute and create a public key token that matches the one specified.
        var internalsVisisbleTo = mvcAssembly.GetCustomAttributes(typeof (InternalsVisibleToAttribute),true).FirstOrDefault() as InternalsVisibleToAttribute;
        var publicKeyString = internalsVisisbleTo.AssemblyName.Split("=".ToCharArray())[1];
        var publicKey = ToBytes(publicKeyString);

        // Create a fake System.Web.Mvc.Test assembly with the public key token set
        AssemblyName assemblyName = new AssemblyName();
        assemblyName.Name = "System.Web.Mvc.Test";
        assemblyName.SetPublicKey(publicKey);

        // Get the domain of our current thread to host the new fake assembly
        var domain = Thread.GetDomain();
        var assemblyBuilder = domain.DefineDynamicAssembly(assemblyName,AssemblyBuilderAccess.RunAndSave);
        moduleBuilder = assemblyBuilder.DefineDynamicModule("System.Web.Mvc.Test","System.Web.Mvc.Test.dll");
        AppDomain currentDom = domain;
        currentDom.TypeResolve += ResolveEvent;

        // Create a new type that inherits from the provided generic and implements the IBuildManager interface
        var typeBuilder = moduleBuilder.DefineType("Cheat",TypeAttributes.NotPublic | TypeAttributes.Class,typeof(T),new Type[] { buildManagerInterface });      
        Type cheatType = typeBuilder.CreateType();

        // Magic!
        var ret = Activator.CreateInstance(cheatType) as T;

        return ret;
    }

    private static byte[] ToBytes(string str)
    {
        List<Byte> bytes = new List<Byte>();

        while(str.Length > 0)
        {
            var bstr = str.Substring(0,2);
            bytes.Add(Convert.ToByte(bstr,16));
            str = str.Substring(2);
        }

        return bytes.ToArray();
    }

    private static ModuleBuilder moduleBuilder;

    private static Assembly ResolveEvent(Object sender,ResolveEventArgs args)
    {
        return moduleBuilder.Assembly;
    }

    public virtual bool FileExists(string virtualPath)      { throw new NotImplementedException(); }
    public virtual Type GetCompiledType(string virtualPath) { throw new NotImplementedException(); }
    public virtual ICollection GetReferencedAssemblies()    { throw new NotImplementedException(); }
    public virtual Stream ReadCachedFile(string fileName)   { throw new NotImplementedException(); }
    public virtual Stream CreateCachedFile(string fileName) { throw new NotImplementedException(); }
}