Added metric for field count

Author: niemyjski

src/Exceptionless.Core/Pipeline/035_CopySimpleDataToIdxAction.cs

@@ -1,19 +1,32 @@
 using System;
 using System.Threading.Tasks;
+using Exceptionless.Core.AppStats;
 using Exceptionless.Core.Plugins.EventProcessor;
+using Foundatio.Metrics;
 using Microsoft.Extensions.Logging;
 
 namespace Exceptionless.Core.Pipeline {
     [Priority(40)]
     public class CopySimpleDataToIdxAction : EventPipelineActionBase {
-        public CopySimpleDataToIdxAction(ILoggerFactory loggerFactory = null) : base(loggerFactory) {}
+        private readonly IMetricsClient _metricsClient;
+
+        public CopySimpleDataToIdxAction(IMetricsClient metricsClient, ILoggerFactory loggerFactory = null) : base(loggerFactory) {
+            _metricsClient = metricsClient;
+        }
 
         public override Task ProcessAsync(EventContext ctx) {
             if (!ctx.Organization.HasPremiumFeatures)
                 return Task.CompletedTask;
 
             // TODO: Do we need a pipeline action to trim keys and remove null values that may be sent by other native clients.
             ctx.Event.CopyDataToIndex(Array.Empty<string>());
+            int fieldCount = ctx.Event.Idx.Count;
+            _metricsClient.Gauge(MetricNames.EventsFieldCount, fieldCount);
+            if (fieldCount > 20 && _logger.IsEnabled(LogLevel.Warning)) {
+                var ev = ctx.Event;
+                using (_logger.BeginScope(new ExceptionlessState().Organization(ctx.Organization.Id).Property("Event", new { ev.Date, ev.StackId, ev.Type, ev.Source, ev.Message, ev.Value, ev.Geo, ev.ReferenceId, ev.Tags, ev.Idx })))
+                    _logger.LogWarning("Event has {FieldCount} indexed fields.", fieldCount);
+            }
 
             return Task.CompletedTask;
         }

src/Exceptionless.Core/Utility/MetricNames.cs

@@ -10,6 +10,7 @@ public static class MetricNames {
         public const string EventsProcessCancelled = "events.processing.cancelled";
         public const string EventsRetryCount = "events.retry.count";
         public const string EventsRetryErrors = "events.retry.errors";
+        public const string EventsFieldCount = "events.field.count";
 
         public const string PostsParsed = "posts.parsed";
         public const string PostsEventCount = "posts.eventcount";