private bool Match(string attribute, Regex regex, MetricsHelper <T> helper, bool reject)
{
string value;
try
{
value = helper.Resolve(attribute);
}
catch (Exception)
{
return(!reject);
}
return(regex.IsMatch(value));
}
public Entry?GetMatching(MetricsHelper <T> helper, Entry?previous)
{
//
// Check the accept and reject filters.
//
foreach (KeyValuePair <string, Regex> e in _accept)
{
if (!Match(e.Key, e.Value, helper, false))
{
return(null);
}
}
foreach (KeyValuePair <string, Regex> e in _reject)
{
if (Match(e.Key, e.Value, helper, true))
{
return(null);
}
}
//
// Compute the key from the GroupBy property.
//
string key;
try
{
if (_groupByAttributes.Count == 1)
{
key = helper.Resolve(_groupByAttributes[0]);
}
else
{
var os = new StringBuilder();
IEnumerator <string> q = _groupBySeparators.GetEnumerator();
foreach (string p in _groupByAttributes)
{
os.Append(helper.Resolve(p));
if (q.MoveNext())
{
os.Append(q.Current);
}
}
key = os.ToString();
}
}
catch (Exception)
{
return(null);
}
//
// Lookup the metrics object.
//
lock (this)
{
if (previous != null && previous.GetId().Equals(key))
{
Debug.Assert(_objects[key] == previous);
return(previous);
}
if (!_objects.TryGetValue(key, out MetricsMap <T> .Entry? e))
{
try
{
var t = new T();
t.Id = key;
e = new Entry(this, t);
_objects.Add(key, e);
}
catch (Exception)
{
Debug.Assert(false);
}
}
e.Attach(helper);
return(e);
}
}
internal Entry?GetMatching(MetricsHelper <T> helper, Entry?previous)
{
// Check the accept filters.
foreach ((string name, Regex value) in _accept)
{
if (!Match(name, value, helper, false))
{
return(null);
}
}
// Check the reject filters.
foreach ((string name, Regex value) in _reject)
{
if (Match(name, value, helper, true))
{
return(null);
}
}
// Compute the key from the GroupBy property.
string key;
try
{
if (_groupByAttributes.Count == 1)
{
key = helper.Resolve(_groupByAttributes[0]);
}
else
{
var os = new StringBuilder();
IEnumerator <string> q = _groupBySeparators.GetEnumerator();
foreach (string p in _groupByAttributes)
{
os.Append(helper.Resolve(p));
if (q.MoveNext())
{
os.Append(q.Current);
}
}
key = os.ToString();
}
}
catch
{
return(null);
}
// Lookup the metrics object.
lock (_mutex)
{
if (previous != null && previous.Id.Equals(key))
{
Debug.Assert(_entries[key] == previous);
return(previous);
}
if (!_entries.TryGetValue(key, out MetricsMap <T> .Entry? e))
{
var t = new T();
t.Id = key;
e = new Entry(_mutex, this, t);
_entries.Add(key, e);
}
e.Attach(helper);
return(e);
}
}