private static XmlDocument CreateXmlContent(ImageServer.Common.Alert alert)
{
XmlDocument doc = new XmlDocument();
XmlNode docElement = doc.CreateElement("Contents");
doc.AppendChild(docElement);
XmlNode messageNode = doc.CreateElement("Message");
messageNode.AppendChild(doc.CreateTextNode(alert.Message));
docElement.AppendChild(messageNode);
if (alert.ContextData != null)
{
XmlNode contextContainerNode = doc.CreateElement("Context");
XmlNode contextNode = doc.ImportNode(XmlUtils.Serialize(alert.ContextData, false), true);
contextContainerNode.AppendChild(contextNode);
docElement.AppendChild(contextContainerNode);
}
return(doc);
}
static private string ResolveKey(ImageServer.Common.Alert alert)
{
Platform.CheckForNullReference(alert, "alert");
Platform.CheckForNullReference(alert.Source, "alert.Source");
string key = String.Format("{0}/{1}/{2}/{3}",
alert.Source.Host, alert.Source.Name, alert.Code, alert.ContextData);
return(key);
}
public void GenerateAlert(ImageServer.Common.Alert alert)
{
IAlertServiceExtension[] extensions = GetExtensions();
foreach (IAlertServiceExtension ext in extensions)
{
try
{
ext.OnAlert(alert);
}
catch (Exception e)
{
Platform.Log(LogLevel.Error, e, "Error occurred when calling {0} OnAlert()", ext.GetType());
}
}
}
public void OnAlert(ImageServer.Common.Alert alert)
{
AlertFilter filter = new AlertFilter(AlertCache.Instance);
if (!filter.Filter(alert))
{
AlertCache.Instance.Add(alert);
if (DatabaseEnabled)
{
WriteToDatabase(alert);
}
else
{
WriteToLog(alert);
}
}
}
/// <summary>
/// Adds an alert into the cache.
/// </summary>
/// <param name="alert"></param>
public void Add(ImageServer.Common.Alert alert)
{
lock (_syncLock)
{
_listAlerts.Add(alert);
}
_cache.Add(ResolveKey(alert), alert, null, alert.ExpirationTime, Cache.NoSlidingExpiration, CacheItemPriority.Normal,
delegate(string key, Object value, CacheItemRemovedReason reason)
{
// Discovered an exception here when debugging that may have caused the service to
// crash. This delegate was called, however, the alert was not in the cache
lock (_syncLock)
{
if (_listAlerts.Contains((ImageServer.Common.Alert)value))
{
_listAlerts.Remove((ImageServer.Common.Alert)value);
}
}
});
}
private static void WriteToLog(ImageServer.Common.Alert alert)
{
XmlDocument doc = CreateXmlContent(alert);
using (StringWriter sw = new StringWriter())
{
XmlWriterSettings settings = new XmlWriterSettings();
settings.Indent = true;
settings.NewLineOnAttributes = false;
settings.OmitXmlDeclaration = true;
settings.Encoding = Encoding.UTF8;
XmlWriter writer = XmlWriter.Create(sw, settings);
doc.WriteTo(writer);
writer.Flush();
String log = String.Format("ALERT: {0} : {1}", alert.Source.Name, sw);
switch (alert.Level)
{
case AlertLevel.Critical:
case AlertLevel.Error:
Platform.Log(LogLevel.Error, log);
break;
case AlertLevel.Informational:
Platform.Log(LogLevel.Info, log);
break;
case AlertLevel.Warning:
Platform.Log(LogLevel.Warn, log);
break;
default:
Platform.Log(LogLevel.Info, log);
break;
}
}
}
private static void WriteToDatabase(ImageServer.Common.Alert alert)
{
XmlDocument doc = CreateXmlContent(alert);
AlertUpdateColumns columns = new AlertUpdateColumns();
columns.AlertCategoryEnum = AlertCategoryEnum.GetEnum(alert.Category.ToString());
columns.AlertLevelEnum = AlertLevelEnum.GetEnum(alert.Level.ToString());
columns.Component = alert.Source.Name;
columns.Content = doc;
columns.InsertTime = Platform.Time;
columns.Source = alert.Source.Host;
columns.TypeCode = alert.Code;
IPersistentStore store = PersistentStoreRegistry.GetDefaultStore();
using (IUpdateContext ctx = store.OpenUpdateContext(UpdateContextSyncMode.Flush))
{
IAlertEntityBroker alertBroker = ctx.GetBroker <IAlertEntityBroker>();
alertBroker.Insert(columns);
ctx.Commit();
}
}
public bool Filter(ImageServer.Common.Alert alert)
{
return(_cache.Contains(alert));
}
/// <summary>
/// Gets a value indicating whether the specified alert or another alert that represents the same event is already in the cache.
/// </summary>
/// <param name="alert"></param>
/// <returns></returns>
public bool Contains(ImageServer.Common.Alert alert)
{
lock (_syncLock)
return(_listAlerts.Contains(alert));
}
