Tracing: Adds tracing improvements for pkrange refresh calls

Microsoft.Azure.Cosmos/src/MetadataRequestThrottleRetryPolicy.cs

@@ -53,6 +53,11 @@ internal sealed class MetadataRequestThrottleRetryPolicy : IDocumentClientRetryP
         /// </summary>
         private int unavailableEndpointRetryCount;
 
+        /// <summary>
+        /// The request being sent to the service.
+        /// </summary>
+        private DocumentServiceRequest request;
+
         /// <summary>
         /// The constructor to initialize an instance of <see cref="MetadataRequestThrottleRetryPolicy"/>.
         /// </summary>
@@ -93,6 +98,12 @@ public Task<ShouldRetryResult> ShouldRetryAsync(
         {
             if (exception is CosmosException cosmosException)
             {
+                DefaultTrace.TraceInformation("MetadataRequestThrottleRetryPolicy: Evaluating retry for CosmosException with StatusCode: {0}, SubStatusCode: {1}, ResourceType {2}, CollectionName {3}, ResourceID {4}.", 
+                    cosmosException.StatusCode, 
+                    cosmosException.SubStatusCode,
+                    this.request.ResourceType,
+                    this.request.CollectionName,
+                    this.request.ResourceId);
                 return this.ShouldRetryInternalAsync(
                     cosmosException.StatusCode, 
                     (SubStatusCodes)cosmosException.SubStatusCode,
@@ -102,11 +113,27 @@ public Task<ShouldRetryResult> ShouldRetryAsync(
 
             if (exception is DocumentClientException clientException)
             {
+                DefaultTrace.TraceInformation("MetadataRequestThrottleRetryPolicy: Evaluating retry for DocumentClientException with StatusCode: {0}, SubStatusCode: {1}, ResourceType {2}, CollectionName {3}, ResourceID {4}", 
+                    clientException.StatusCode, 
+                    clientException.GetSubStatus(),
+                    this.request.ResourceType,
+                    this.request.CollectionName,
+                    this.request.ResourceId);
                 return this.ShouldRetryInternalAsync(
                     clientException.StatusCode,
                     clientException.GetSubStatus(),
                     exception, cancellationToken);
             }
+            else
+            {
+                DefaultTrace.TraceInformation("MetadataRequestThrottleRetryPolicy: Evaluating retry for Exception of type: {0}, Message: {1}, ResourceType {2}, CollectionName {3}, ResourceID {4}", 
+                    exception.GetType().Name,
+                    exception.Message,
+                    this.request.ResourceType,
+                    this.request.CollectionName,
+                    this.request.ResourceId);
+
+            }
 
             return this.throttlingRetryPolicy.ShouldRetryAsync(exception, cancellationToken);
         }
@@ -186,14 +213,20 @@ private Task<ShouldRetryResult> ShouldRetryInternalAsync(
         public void OnBeforeSendRequest(DocumentServiceRequest request)
         {
             // Clear the previous location-based routing directive.
+            this.request = request;
             request.RequestContext.ClearRouteToLocation();
             request.RequestContext.RouteToLocation(
                 this.retryContext.RetryLocationIndex,
                 this.retryContext.RetryRequestOnPreferredLocations);
 
             Uri metadataLocationEndpoint = this.globalEndpointManager.ResolveServiceEndpoint(request);
 
-            DefaultTrace.TraceInformation("MetadataRequestThrottleRetryPolicy: Routing the metadata request to: {0} for operation type: {1} and resource type: {2}.", metadataLocationEndpoint, request.OperationType, request.ResourceType);
+            DefaultTrace.TraceInformation("MetadataRequestThrottleRetryPolicy: Routing the metadata request to: {0} for operation type: {1} and resource type: {2} for collection: {3} with collection rid {4}.", 
+                metadataLocationEndpoint, 
+                request.OperationType, 
+                request.ResourceType, 
+                request.CollectionName, 
+                request.ResourceId);
             request.RequestContext.RouteToLocation(metadataLocationEndpoint);
         }
 

Microsoft.Azure.Cosmos/src/Routing/PartitionKeyRangeCache.cs

@@ -213,6 +213,16 @@ private async Task<CollectionRoutingMap> GetRoutingMapForCollectionAsync(
                     lastStatusCode = response.StatusCode;
                     changeFeedNextIfNoneMatch = response.Headers[HttpConstants.HttpHeaders.ETag];
 
+                    DefaultTrace.TraceInformation("PartitionKeyRangeCache GetRoutingMapForCollectionAsync collectionRid: {0}, StatusCode: {1}, SubstatusCode {2}, request Etag {3}, response ETag: {4}, RegionsContacted {5}", 
+                        collectionRid,
+                        lastStatusCode,
+                        response.GetSubStatusCodes(),
+                        headers.GetHeaderValue<string>(HttpConstants.HttpHeaders.IfNoneMatch),
+                        changeFeedNextIfNoneMatch,
+                        response.RequestStats?.RegionsContacted != null
+                            ? string.Join(", ", response.RequestStats.RegionsContacted)
+                            : string.Empty);
+
                     FeedResource<PartitionKeyRange> feedResource = response.GetResource<FeedResource<PartitionKeyRange>>();
                     if (feedResource != null)
                     {