/// <summary>
/// Create a new value definition from the provided information.
/// </summary>
/// <param name="definition">The metric definition that owns this value definition</param>
/// <param name="packet">The prepopulated value definition packet.</param>
internal EventMetricValueDefinition(EventMetricDefinition definition, EventMetricValueDefinitionPacket packet)
{
m_Definition = definition;
m_Packet = packet;
//and determine if it is trendable or not
m_Trendable = EventMetricDefinition.IsTrendableValueType(m_Packet.Type);
MyIndex = -1; // Mark it as unknown.
}
/// <summary>
/// Records a value to the values array of this sample given its value definition.
/// </summary>
/// <remarks>The value must be defined as part of the event metric definition associated with this sample
/// or an exception will be thrown. The data type must also be compatible with the data type configured
/// on the event metric definition or no data will be recorded.
/// If called more than once for the same value, the prior value will be replaced.</remarks>
/// <param name="valueDefinition">The metric value definition object of the value to be recorded.</param>
/// <param name="value">The value to be recorded.</param>
public void SetValue(EventMetricValueDefinition valueDefinition, object value)
{
//make sure we got a value definition
if (valueDefinition == null)
{
throw new ArgumentNullException(nameof(valueDefinition));
}
//look up the numerical index in the collection so we know what offset to put it in the array at
int valueIndex = Metric.Definition.Values.IndexOf(valueDefinition);
//if we didn't find it, we're hosed
if (valueIndex < 0)
{
#if DEBUG
//if we're compiled in debug mode, tell the user they blew it.
throw new ArgumentOutOfRangeException(nameof(valueDefinition), valueDefinition.Name);
#else
//log and return, nothing we can do.
if (!Log.SilentMode)
{
Log.Write(LogMessageSeverity.Warning, LogCategory, "Unable to add metric value to the current sample due to missing value definition",
"There is no value definition named {1} for metric definition {0}",
Metric.Definition.Name, valueDefinition.Name);
}
return;
#endif
}
//coerce it into the right type
object storedValue;
if (value == null)
{
//you can always store a null. And we can't really check it more, so there.
storedValue = null;
}
else
{
//get the type so we can verify it
Type valueType = value.GetType();
//is it close enough to what we're expecting?
if (valueDefinition.IsTrendable)
{
if (EventMetricDefinition.IsTrendableValueType(valueType))
{
storedValue = value;
}
else
{
//no, it should be trendable and it isn't. store null.
storedValue = null;
}
}
else
{
//we don't care what it is because we're going to coerce it to a string.
storedValue = value.ToString();
}
}
//now write out the value to the correct spot in the array
Packet.Values[valueIndex] = storedValue;
}