private static List <Type> ReadTypesFromCache(
string cacheName,
Predicate <Type> predicate,
HttpControllerTypeCacheSerializer serializer
)
{
try
{
Stream stream = BuildManager.ReadCachedFile(cacheName);
if (stream != null)
{
using (StreamReader reader = new StreamReader(stream))
{
ICollection <Type> deserializedTypes = serializer.DeserializeTypes(reader);
if (
deserializedTypes != null &&
deserializedTypes.All(type => predicate(type))
)
{
// If all read types still match the predicate, success!
return(deserializedTypes.ToList());
}
}
}
}
catch
{
// cache failures are not considered fatal -- keep running.
}
return(null);
}
/// <summary>
/// Returns a list of controllers available for the application.
/// </summary>
/// <returns>An <see cref="ICollection{Type}" /> of controllers.</returns>
public override ICollection <Type> GetControllerTypes(IAssembliesResolver assembliesResolver)
{
HttpControllerTypeCacheSerializer serializer = new HttpControllerTypeCacheSerializer();
// First, try reading from the cache on disk
List <Type> matchingTypes = ReadTypesFromCache(TypeCacheName, IsControllerTypePredicate, serializer);
if (matchingTypes != null)
{
return(matchingTypes);
}
// If reading from the cache failed, enumerate over every assembly looking for a matching type
matchingTypes = base.GetControllerTypes(assembliesResolver).ToList();
// Finally, save the cache back to disk
SaveTypesToCache(TypeCacheName, matchingTypes, serializer);
return(matchingTypes);
}
private static void SaveTypesToCache(
string cacheName,
IEnumerable <Type> matchingTypes,
HttpControllerTypeCacheSerializer serializer
)
{
try
{
Stream stream = BuildManager.CreateCachedFile(cacheName);
if (stream != null)
{
using (StreamWriter writer = new StreamWriter(stream))
{
serializer.SerializeTypes(matchingTypes, writer);
}
}
}
catch
{
// cache failures are not considered fatal -- keep running.
}
}