public SafeDirectoryCatalog(string directory,
Func <Type, bool> typeFilter = null,
ReflectionContext reflectionContext = null,
Func <string, bool> fileFilter = null)
{
// cf.: http://stackoverflow.com/a/4475117/2592915
_dirInfo = new DirectoryInfo(directory);
Catalog = new AggregateCatalog();
var safeFileFilter = fileFilter ?? (fileName => true);
var files = _dirInfo.EnumerateFiles("*.dll", SearchOption.AllDirectories)
.Where(file => safeFileFilter(file.FullName));
foreach (var file in files)
{
try
{
var catalog = new SafeAssemblyCatalog(file.FullName, typeFilter, reflectionContext);
//Force MEF to load the plugin and figure out if there are any exports.
// good assemblies will not throw the RTLE exception and can be added to the catalog
if (catalog.Parts.ToList().Count <= 0)
{
continue;
}
Catalog.Catalogs.Add(catalog);
Assemblies.Add(catalog.Assembly);
}
catch (Exception ex) when(ex is ReflectionTypeLoadException || ex is BadImageFormatException)
{
Trace.WriteLine($"Could not load '{file.FullName}': {ex}");
}
}
}
public void Use_type_filter()
{
var expected = typeof(SafeAssemblyCatalog_Should);
using (var sut = new SafeAssemblyCatalog(Assembly.GetExecutingAssembly(), type => type == expected))
{
// "is a" ReflectionComposablePartDefinition(), so we use "ToString()" to check
// cf.: https://mef.codeplex.com/SourceControl/latest#redist/src/ComponentModel/System/ComponentModel/Composition/ReflectionModel/ReflectionComposablePartDefinition.cs
var part = sut.Parts.Single();
part.ToString().Should().Be(expected.FullName);
var importDefinition = new ImportDefinition(e => false, "contract", ImportCardinality.ExactlyOne, false,
false);
sut.GetExports(importDefinition).Should().BeEmpty();
}
}
