/// <summary>
/// Returns a unique hash for the combination of FileInfo objects passed in
/// </summary>
/// <param name="filesAndFolders"></param>
/// <returns></returns>
internal static long GetAssembliesHash(IEnumerable <FileSystemInfo> filesAndFolders)
{
using (DisposableTimer.TraceDuration <PluginManager>("Determining hash of code files on disk", "Hash determined"))
{
var hashCombiner = new HashCodeCombiner();
//add each unique folder to the hash
foreach (var i in filesAndFolders.DistinctBy(x => x.FullName))
{
hashCombiner.AddFileSystemItem(i);
}
return(ConvertPluginsHashFromHex(hashCombiner.GetCombinedHashCode()));
}
}
private IEnumerable <Type> ResolveTypes <T>(
Func <IEnumerable <Type> > finder,
TypeResolutionKind resolutionType,
bool cacheResult)
{
using (var readLock = new UpgradeableReadLock(_lock))
{
using (DisposableTimer.TraceDuration <PluginManager>(
String.Format("Starting resolution types of {0}", typeof(T).FullName),
String.Format("Completed resolution of types of {0}", typeof(T).FullName)))
{
//check if the TypeList already exists, if so return it, if not we'll create it
var typeList = _types.SingleOrDefault(x => x.IsTypeList <T>(resolutionType));
//if we're not caching the result then proceed, or if the type list doesn't exist then proceed
if (!cacheResult || typeList == null)
{
//upgrade to a write lock since we're adding to the collection
readLock.UpgradeToWriteLock();
typeList = new TypeList <T>(resolutionType);
foreach (var t in finder())
{
typeList.AddType(t);
}
//only add the cache if we are to cache the results
if (cacheResult)
{
//add the type list to the collection
_types.Add(typeList);
}
}
return(typeList.GetTypes());
}
}
}
private IEnumerable <Type> ResolveTypes <T>(
Func <IEnumerable <Type> > finder,
TypeResolutionKind resolutionType,
bool cacheResult)
{
using (var readLock = new UpgradeableReadLock(_lock))
{
var typesFound = new List <Type>();
using (DisposableTimer.TraceDuration <PluginManager>(
() => String.Format("Starting resolution types of {0}", typeof(T).FullName),
() => String.Format("Completed resolution of types of {0}, found {1}", typeof(T).FullName, typesFound.Count)))
{
//check if the TypeList already exists, if so return it, if not we'll create it
var typeList = _types.SingleOrDefault(x => x.IsTypeList <T>(resolutionType));
//if we're not caching the result then proceed, or if the type list doesn't exist then proceed
if (!cacheResult || typeList == null)
{
//upgrade to a write lock since we're adding to the collection
readLock.UpgradeToWriteLock();
typeList = new TypeList <T>(resolutionType);
//we first need to look into our cache file (this has nothing to do with the 'cacheResult' parameter which caches in memory).
//if assemblies have not changed and the cache file actually exists, then proceed to try to lookup by the cache file.
if (!HaveAssembliesChanged && File.Exists(GetPluginListFilePath()))
{
var fileCacheResult = TryGetCachedPluginsFromFile <T>(resolutionType);
//here we need to identify if the CachedPluginNotFoundInFile was the exception, if it was then we need to re-scan
//in some cases the plugin will not have been scanned for on application startup, but the assemblies haven't changed
//so in this instance there will never be a result.
if (fileCacheResult.Error != null && fileCacheResult.Error is CachedPluginNotFoundInFile)
{
//we don't have a cache for this so proceed to look them up by scanning
LoadViaScanningAndUpdateCacheFile <T>(typeList, resolutionType, finder);
}
else
{
if (fileCacheResult.Success)
{
var successfullyLoadedFromCache = true;
//we have a previous cache for this so we don't need to scan we just load what has been found in the file
foreach (var t in fileCacheResult.Result)
{
try
{
//we use the build manager to ensure we get all types loaded, this is slightly slower than
//Type.GetType but if the types in the assembly aren't loaded yet then we have problems with that.
var type = BuildManager.GetType(t, true);
typeList.AddType(type);
}
catch (Exception ex)
{
//if there are any exceptions loading types, we have to exist, this should never happen so
//we will need to revert to scanning for types.
successfullyLoadedFromCache = false;
LogHelper.Error <PluginManager>("Could not load a cached plugin type: " + t + " now reverting to re-scanning assemblies for the base type: " + typeof(T).FullName, ex);
break;
}
}
if (!successfullyLoadedFromCache)
{
//we need to manually load by scanning if loading from the file was not successful.
LoadViaScanningAndUpdateCacheFile <T>(typeList, resolutionType, finder);
}
else
{
LogHelper.Debug <PluginManager>("Loaded plugin types " + typeof(T).FullName + " from persisted cache");
}
}
}
}
else
{
//we don't have a cache for this so proceed to look them up by scanning
LoadViaScanningAndUpdateCacheFile <T>(typeList, resolutionType, finder);
}
//only add the cache if we are to cache the results
if (cacheResult)
{
//add the type list to the collection
_types.Add(typeList);
}
}
typesFound = typeList.GetTypes().ToList();
}
return(typesFound);
}
}
