void SetPluginStatus(PluginProxy plugin, RunningStatus newOne, bool allowErrorTransition)
{
RunningStatus previous = plugin.Status;
Debug.Assert(previous != newOne);
if (newOne > previous)
{
// New status is greater than the previous one.
// We first set the plugin (and raise the event) and then raise the service event (if any).
DoSetPluginStatus(plugin, newOne, previous);
if (plugin.IsCurrentServiceImplementation)
{
if (newOne == RunningStatus.Stopped && plugin.Service.Status == RunningStatus.Stopped)
{
// This is an consequence of the fact that we disable plugins after
// starting the new ones.
// When pA (stopping) implements sA and pB implements sA (starting), sA remains "Stopped".
}
else
{
plugin.Service.SetStatusChanged(newOne, allowErrorTransition);
}
}
}
else
{
// New status is lower than the previous one.
// We first raise the service event (if any) and then the plugin event.
if (plugin.IsCurrentServiceImplementation)
{
plugin.Service.SetStatusChanged(newOne, allowErrorTransition);
}
DoSetPluginStatus(plugin, newOne, previous);
}
}
private void DoSetPluginStatus(PluginProxy plugin, RunningStatus newOne, RunningStatus previous)
{
plugin.Status = newOne;
var h = StatusChanged;
if (h != null)
{
h(this, new PluginStatusChangedEventArgs(previous, plugin));
}
}
PluginProxy EnsureProxy(IPluginInfo key)
{
PluginProxy result;
if (!_plugins.TryGetValue(key, out result))
{
result = new PluginProxy(key);
_plugins.Add(key, result);
}
return(result);
}
private void RevokeStartCall(PluginProxy p)
{
try
{
p.RealPlugin.Stop();
}
catch (Exception exStop)
{
// 2.1 - Should be emitted as an external log event.
_serviceHost.LogMethodError(p.GetImplMethodInfoTeardown(), exStop);
}
RevokeSetupCall(p);
}
private void RevokeSetupCall(PluginProxy p)
{
// 2 - Stops the plugin status.
SetPluginStatus(p, RunningStatus.Stopping, true);
// 3 - Safe call to TearDown.
try
{
p.RealPlugin.Teardown();
}
catch (Exception exTeardown)
{
// 2.1 - Should be emitted as an external log event.
_serviceHost.LogMethodError(p.GetImplMethodInfoTeardown(), exTeardown);
}
SetPluginStatus(p, RunningStatus.Stopped, true);
}
private void DoSetPluginStatus( PluginProxy plugin, RunningStatus newOne, RunningStatus previous )
{
plugin.Status = newOne;
var h = StatusChanged;
if( h != null )
{
h( this, new PluginStatusChangedEventArgs( previous, plugin ) );
}
}
void SetPluginStatus( PluginProxy plugin, RunningStatus newOne, bool allowErrorTransition )
{
RunningStatus previous = plugin.Status;
Debug.Assert( previous != newOne );
if( newOne > previous )
{
// New status is greater than the previous one.
// We first set the plugin (and raise the event) and then raise the service event (if any).
DoSetPluginStatus( plugin, newOne, previous );
if( plugin.IsCurrentServiceImplementation )
{
if( newOne == RunningStatus.Stopped && plugin.Service.Status == RunningStatus.Stopped )
{
// This is an consequence of the fact that we disable plugins after
// starting the new ones.
// When pA (stopping) implements sA and pB implements sA (starting), sA remains "Stopped".
}
else plugin.Service.SetStatusChanged( newOne, allowErrorTransition );
}
}
else
{
// New status is lower than the previous one.
// We first raise the service event (if any) and then the plugin event.
if( plugin.IsCurrentServiceImplementation ) plugin.Service.SetStatusChanged( newOne, allowErrorTransition );
DoSetPluginStatus( plugin, newOne, previous );
}
}
void SetPluginStatus( PluginProxy plugin, RunningStatus newOne )
{
SetPluginStatus( plugin, newOne, false );
}
PluginProxy EnsureProxy( IPluginInfo key )
{
PluginProxy result;
if( !_plugins.TryGetValue( key, out result ) )
{
result = new PluginProxy( key );
_plugins.Add( key, result );
}
return result;
}
private void RevokeSetupCall( PluginProxy p )
{
// 2 - Stops the plugin status.
SetPluginStatus( p, RunningStatus.Stopping, true );
// 3 - Safe call to TearDown.
try
{
p.RealPlugin.Teardown();
}
catch( Exception exTeardown )
{
// 2.1 - Should be emitted as an external log event.
_serviceHost.LogMethodError( p.GetImplMethodInfoTeardown(), exTeardown );
}
SetPluginStatus( p, RunningStatus.Stopped, true );
}
private void RevokeStartCall( PluginProxy p )
{
try
{
p.RealPlugin.Stop();
}
catch( Exception exStop )
{
// 2.1 - Should be emitted as an external log event.
_serviceHost.LogMethodError( p.GetImplMethodInfoTeardown(), exStop );
}
RevokeSetupCall( p );
}
void SetPluginStatus(PluginProxy plugin, RunningStatus newOne)
{
SetPluginStatus(plugin, newOne, false);
}
/// <summary>
/// Attempts to execute a plan.
/// </summary>
/// <param name="disabledPluginKeys">Plugins that must be disabled.</param>
/// <param name="stoppedPluginKeys">Plugins that must be stopped.</param>
/// <param name="runningPluginKeys">Plugins that must be running.</param>
/// <returns>A <see cref="IExecutionPlanError"/> that details the error if any.</returns>
public IExecutionPlanResult Execute(IEnumerable <IPluginInfo> disabledPluginKeys, IEnumerable <IPluginInfo> stoppedPluginKeys, IEnumerable <IPluginInfo> runningPluginKeys)
{
if (PluginCreator == null)
{
throw new InvalidOperationException(R.PluginCreatorIsNull);
}
if (ServiceReferencesBinder == null)
{
throw new InvalidOperationException(R.PluginConfiguratorIsNull);
}
int nbIntersect;
nbIntersect = disabledPluginKeys.Intersect(stoppedPluginKeys).Count();
if (nbIntersect != 0)
{
throw new CKException(R.DisabledAndStoppedPluginsIntersect, nbIntersect);
}
nbIntersect = disabledPluginKeys.Intersect(runningPluginKeys).Count();
if (nbIntersect != 0)
{
throw new CKException(R.DisabledAndRunningPluginsIntersect, nbIntersect);
}
nbIntersect = stoppedPluginKeys.Intersect(runningPluginKeys).Count();
if (nbIntersect != 0)
{
throw new CKException(R.StoppedAndRunningPluginsIntersect, nbIntersect);
}
List <PluginProxy> toDisable = new List <PluginProxy>();
List <PluginProxy> toStop = new List <PluginProxy>();
List <PluginProxy> toStart = new List <PluginProxy>();
foreach (IPluginInfo k in disabledPluginKeys)
{
PluginProxy p = EnsureProxy(k);
if (p.Status != RunningStatus.Disabled)
{
toDisable.Add(p);
if (p.Status != RunningStatus.Stopped)
{
toStop.Add(p);
}
}
}
foreach (IPluginInfo k in stoppedPluginKeys)
{
PluginProxy p = EnsureProxy(k);
if (p.Status != RunningStatus.Stopped)
{
toStop.Add(p);
}
}
// The lists toDisable and toStop are correctly filled.
// A plugin can be in both lists if it must be stopped and then disabled.
// Now, we attempt to activate the plugins that must run: if an error occurs,
// we leave and return the error since we did not change anything.
foreach (IPluginInfo k in runningPluginKeys)
{
PluginProxy p = EnsureProxy(k);
if (!p.IsLoaded)
{
if (!p.TryLoad(_serviceHost, PluginCreator))
{
Debug.Assert(p.LoadError != null);
_serviceHost.LogMethodError(PluginCreator.Method, p.LoadError);
// Unable to load the plugin: leave now.
return(new ExecutionPlanResult()
{
Culprit = p.PluginKey, Status = ExecutionPlanResultStatus.LoadError
});
}
Debug.Assert(p.LoadError == null);
Debug.Assert(p.Status == RunningStatus.Disabled);
_newlyLoadedPlugins.Add(p);
}
if (p.Status != RunningStatus.Started)
{
toStart.Add(p);
}
}
// The toStart list is ready: plugins inside are loaded without error.
// We stop all "toStop" plugin.
// Their "stop" methods will be called.
foreach (PluginProxy p in toStop)
{
if (p.Status > RunningStatus.Stopped)
{
try
{
SetPluginStatus(p, RunningStatus.Stopping);
p.RealPlugin.Stop();
_log.Debug(String.Format("The {0} plugin has been successfully stopped.", p.PublicName));
}
catch (Exception ex)
{
#if DEBUG
//Helps the developper identify the culprit of exception
Debugger.Break();
#endif
_log.ErrorFormat("There has been a problem when stopping the {0} plugin.", ex, p.PublicName);
_serviceHost.LogMethodError(p.GetImplMethodInfoStop(), ex);
}
}
}
// We un-initialize all "toStop" plugin.
// Their "Teardown" methods will be called.
// After that, they are all "stopped".
foreach (PluginProxy p in toStop)
{
try
{
if (p.Status > RunningStatus.Stopped)
{
SetPluginStatus(p, RunningStatus.Stopped);
p.RealPlugin.Teardown();
_log.Debug(String.Format("The {0} plugin has been successfully torn down.", p.PublicName));
}
}
catch (Exception ex)
{
#if DEBUG
//Helps the developper identify the culprit of exceptions
Debugger.Break();
#endif
_log.ErrorFormat("There has been a problem when tearing down the {0} plugin.", ex, p.PublicName);
_serviceHost.LogMethodError(p.GetImplMethodInfoTeardown(), ex);
}
}
Debug.Assert(toStop.All(p => p.Status <= RunningStatus.Stopped));
// Prepares the plugins to start so that they become the implementation
// of their Service and are at least stopped (instead of disabled).
foreach (PluginProxy p in toStart)
{
ServiceProxyBase service = p.Service;
// The call to service.SetImplementation, sets the implementation and takes
// the _status of the service into account: this status is at most Stopped
// since we necessarily stopped the previous implementation (if any) above.
if (service != null)
{
Debug.Assert(service.Status <= RunningStatus.Stopped);
service.SetPluginImplementation(p);
}
// This call will trigger an update of the service status.
if (p.Status == RunningStatus.Disabled)
{
SetPluginStatus(p, RunningStatus.Stopped);
}
}
// Now that services have been associated to their new implementation (in Stopped status), we
// can disable the plugins that must be disabled.
foreach (PluginProxy p in toDisable)
{
SetPluginStatus(p, RunningStatus.Disabled);
try
{
p.DisposeIfDisposable();
}
catch (Exception ex)
{
#if DEBUG
//Helps the developper identify the culprit of exceptions
Debugger.Break();
#endif
_log.ErrorFormat("There has been a problem when disposing the {0} plugin.", ex, p.PublicName);
_serviceHost.LogMethodError(p.GetImplMethodInfoDispose(), ex);
}
}
// Before starting
for (int i = 0; i < toStart.Count; i++)
{
PluginProxy p = toStart[i];
// We configure plugin's edition properties.
if (PluginConfigurator != null)
{
PluginConfigurator(p);
}
SetPluginStatus(p, RunningStatus.Starting);
IPluginSetupInfo info = new IPluginSetupInfo();
try
{
p.RealPlugin.Setup(info);
info.Clear();
_log.Debug(String.Format("The {0} plugin has been successfully set up.", p.PublicName));
}
catch (Exception ex)
{
#if DEBUG
//Helps the developper identify the culprit of exceptions
Debugger.Break();
#endif
_log.ErrorFormat("There has been a problem when setting up the {0} plugin.", ex, p.PublicName);
_serviceHost.LogMethodError(p.GetImplMethodInfoSetup(), ex);
// Revoking the call to Setup for all plugins that haven't been started yet.
//Will pass the plugin to states : Stopping and then Stopped
for (int j = 0; j <= i; j++)
{
RevokeSetupCall(toStart[j]);
}
info.Error = ex;
return(new ExecutionPlanResult()
{
Culprit = p.PluginKey, Status = ExecutionPlanResultStatus.SetupError, SetupInfo = info
});
}
}
// Since we are now ready to start new plugins, it is now time to make the external world
// aware of the existence of any new plugins and configure them to run.
foreach (PluginProxy p in _newlyLoadedPlugins)
{
_loadedPlugins.Add(p.PluginKey.UniqueId, p);
}
Debug.Assert(ServiceReferencesBinder != null);
try
{
var listNew = new ReadOnlyCollectionOnICollection <PluginProxy>(_newlyLoadedPlugins);
//var disabled = new ReadOnlyCollectionAdapter<IPluginProxy, PluginProxy>( toDisable );
ServiceReferencesBinder(listNew);
}
catch (Exception ex)
{
_serviceHost.LogMethodError(ServiceReferencesBinder.Method, ex);
}
_newlyLoadedPlugins.Clear();
for (int i = 0; i < toStart.Count; i++)
{
PluginProxy p = toStart[i];
try
{
SetPluginStatus(p, RunningStatus.Started);
p.RealPlugin.Start();
_log.Debug(String.Format("The {0} plugin has been successfully started.", p.PublicName));
}
catch (Exception ex)
{
// Emitted as low level log.
_log.ErrorFormat("There has been a problem when starting the {0} plugin.", ex, p.PublicName);
// Emitted as a log event.
_serviceHost.LogMethodError(p.GetImplMethodInfoStart(), ex);
//All the plugins already started when the exception was thrown have to be stopped + teardown (including this one in exception)
for (int j = 0; j <= i; j++)
{
RevokeStartCall(toStart[j]);
}
// Revoking the call to Setup for all plugins that hadn't been started when the exception occured.
for (int j = i + 1; j < toStart.Count; j++)
{
RevokeSetupCall(toStart[j]);
}
return(new ExecutionPlanResult()
{
Culprit = p.PluginKey, Status = ExecutionPlanResultStatus.LoadError, Error = ex
});
}
}
return(new ExecutionPlanResult());
}
