/// <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());
}
