private static void StartShreds(ShredStartupInfoList shredStartupInfoList)
{
if (null != shredStartupInfoList)
{
// create the data structure that will hold the shreds and their thread, etc. related objects
foreach (ShredStartupInfo shredStartupInfo in shredStartupInfoList)
{
if (null != shredStartupInfo)
{
// clone the shredStartupInfo structure into the current AppDomain, otherwise, once the StagingDomain
// has been unloaded, the shredStartupInfo structure will be destroyed
var newShredStartupInfo = new ShredStartupInfo(shredStartupInfo.AssemblyPath, shredStartupInfo.ShredName,
shredStartupInfo.ShredTypeName, shredStartupInfo.IsolationLevel);
// create the controller that will allow us to start and stop the shred
var shredController = new ShredController(newShredStartupInfo);
_shredInfoList.Add(shredController);
}
}
}
foreach (ShredController shredController in _shredInfoList)
{
shredController.Start();
}
}
/// <summary>
/// Uses the ExtensionPoint type to scan the plugins folder for extensions.
/// </summary>
/// <returns>
/// An enumerable collection that contains information on each extension that will help the loader
/// load them into the AppDomain. If no extensions are found, null is returned.</returns>
public ShredStartupInfoList ScanExtensions()
{
Platform.Log(LogLevel.Debug, this.GetType().ToString() + ":" + this.GetType().Name + " in AppDomain [" + AppDomain.CurrentDomain.FriendlyName + "]");
var shredInfoList = new ShredStartupInfoList();
var xp = new ShredExtensionPoint();
var shredObjects = xp.CreateExtensions();
foreach (var shredObject in shredObjects)
{
var shredType = shredObject.GetType();
var asShred = shredObject as IShred;
if (asShred == null)
{
Platform.Log(LogLevel.Debug, "Shred extension '{0}' does not implement IShred.", shredType.FullName);
continue;
}
var shredIsolation = shredType.GetCustomAttributes(typeof(ShredIsolationAttribute), true).OfType <ShredIsolationAttribute>().FirstOrDefault();
var shredIsolationLevel = shredIsolation == null ? ShredIsolationLevel.OwnAppDomain : shredIsolation.Level;
if (shredIsolationLevel != ShredIsolationLevel.None)
{
Platform.Log(LogLevel.Info, "Shred {0} is running in a seperate app domain", shredType.Name);
}
var assemblyPath = new Uri(shredType.Assembly.CodeBase);
var startupInfo = new ShredStartupInfo(assemblyPath, ((IShred)shredObject).GetDisplayName(), shredType.FullName, shredIsolationLevel);
shredInfoList.Add(startupInfo);
}
return(shredInfoList);
}
/// <summary>
/// Uses the ExtensionPoint type to scan the plugins folder for extensions.
/// </summary>
/// <returns>
/// An enumerable collection that contains information on each extension that will help the loader
/// load them into the AppDomain. If no extensions are found, null is returned.</returns>
public ShredStartupInfoList ScanExtensions()
{
Platform.Log(LogLevel.Debug, this.GetType().ToString() + ":" + this.GetType().Name + " in AppDomain [" + AppDomain.CurrentDomain.FriendlyName + "]");
ShredStartupInfoList shredInfoList = new ShredStartupInfoList();
ShredExtensionPoint xp = new ShredExtensionPoint();
object[] shredObjects = xp.CreateExtensions();
foreach (object shredObject in shredObjects)
{
if (shredObject is IShred)
{
Uri assemblyPath = new Uri(shredObject.GetType().Assembly.CodeBase);
shredInfoList.Add(new ShredStartupInfo(assemblyPath, (shredObject as IShred).GetDisplayName(), shredObject.GetType().FullName));
}
}
return(shredInfoList);
}
/// <summary>
/// Starts the ShredHost routine.
/// </summary>
/// <returns>true - if the ShredHost is currently running, false - if ShredHost is stopped.</returns>
public static bool Start()
{
// install the unhandled exception event handler
AppDomain currentDomain = AppDomain.CurrentDomain;
currentDomain.UnhandledException += MyUnhandledExceptionEventHandler;
lock (_lockObject)
{
if (RunningState.Running == _runningState || RunningState.Transition == _runningState)
{
return(RunningState.Running == _runningState);
}
_runningState = RunningState.Transition;
}
Platform.Log(LogLevel.Info, "Starting up in AppDomain [" + AppDomain.CurrentDomain.FriendlyName + "]");
// the ShredList and shreds objects are proxy objects that actually exist
// in the secondary AppDomain
//AppDomain stagingDomain = AppDomain.CreateDomain("StagingDomain");
ExtensionScanner scanner = (ExtensionScanner)AppDomain.CurrentDomain.CreateInstanceFromAndUnwrap(Assembly.GetExecutingAssembly().Location, "ClearCanvas.Server.ShredHost.ExtensionScanner");
ShredStartupInfoList shredStartupInfoList = null;
try
{
shredStartupInfoList = scanner.ScanExtensions();
}
catch (PluginException pluginException)
{
// There was a problem loading the plugins, including if there were no plugins found
// This is an innocuous problem, and just means that there are no shreds to run
Platform.Log(LogLevel.Warn, pluginException);
}
StartShreds(shredStartupInfoList);
// all the shreds have been created, so we can dismantle the secondary domain that was used
// for scanning for all Extensions that are shreds
//AppDomain.Unload(stagingDomain);
//try
//{
// _sed = WcfHelper.StartHttpHost<ShredHostServiceType, IShredHost>(
// "ShredHost", "Host program of multiple independent service-like sub-programs", ShredHostServiceSettings.Instance.ShredHostHttpPort);
// _shredHostWCFInitialized = true;
// string message = String.Format("The ShredHost WCF service has started on port {0}.", ShredHostServiceSettings.Instance.ShredHostHttpPort);
// Platform.Log(LogLevel.Info, message);
// Console.WriteLine(message);
//}
//catch(Exception e)
//{
// Platform.Log(LogLevel.Error, e);
// Console.WriteLine("The ShredHost WCF service has failed to start. Please check the log for more details.");
//}
lock (_lockObject)
{
_runningState = RunningState.Running;
}
return(RunningState.Running == _runningState);
}
