[Query] Adds public backend metrics property to Diagnostics

Microsoft.Azure.Cosmos/src/Diagnostics/CosmosDiagnostics.cs

@@ -43,6 +43,16 @@ public virtual int GetFailedRequestCount()
             throw new NotImplementedException($"{nameof(CosmosDiagnostics)}.{nameof(GetFailedRequestCount)}");
         }
 
+        /// <summary>
+        ///  This represents the accumulated backend query metrics for the request.
+        /// </summary>
+        /// <returns>The string represemation of the query metrics dictionary.</returns>
+        public virtual BackendAccumulatedMetrics GetQueryMetrics()
+        {
+            // Default implementation avoids breaking change for users upgrading.
+            throw new NotImplementedException($"{nameof(CosmosDiagnostics)}.{nameof(GetQueryMetrics)}");
+        }
+
         /// <summary>
         /// Gets the string field <see cref="CosmosDiagnostics"/> instance in the Azure CosmosDB database service.
         /// </summary>

Microsoft.Azure.Cosmos/src/Diagnostics/CosmosTraceDiagnostics.cs

@@ -9,6 +9,7 @@ namespace Microsoft.Azure.Cosmos.Diagnostics
     using System.Linq;
     using System.Text;
     using Microsoft.Azure.Cosmos.Json;
+    using Microsoft.Azure.Cosmos.Query.Core.Metrics;
     using Microsoft.Azure.Cosmos.Tracing;
     using Microsoft.Azure.Cosmos.Tracing.TraceData;
     using static Microsoft.Azure.Cosmos.Tracing.TraceData.ClientSideRequestStatisticsTraceDatum;
@@ -49,11 +50,42 @@ public override TimeSpan GetClientElapsedTime()
             return this.Value?.Summary?.RegionsContacted;
         }
 
+        public override BackendAccumulatedMetrics GetQueryMetrics()
+        {
+            QueryMetrics queryMetrics = QueryMetrics.Empty;
+            this.WalkTraceTreeForQueryMetrics(this.Value, ref queryMetrics);
+            return new BackendAccumulatedMetrics(queryMetrics);
+        }
+
         internal bool IsGoneExceptionHit()
         {
             return this.WalkTraceTreeForGoneException(this.Value);
         }
 
+        private bool WalkTraceTreeForQueryMetrics(ITrace currentTrace, ref QueryMetrics queryMetrics)
+        {
+            if (currentTrace == null)
+            {
+                return false;
+            }
+
+            foreach (object datums in currentTrace.Data.Values)
+            {
+                if (datums is QueryMetricsTraceDatum queryMetricsTraceDatum)
+                {
+                    queryMetrics += queryMetricsTraceDatum.QueryMetrics;
+                    return true;
+                }
+            }
+
+            foreach (ITrace childTrace in currentTrace.Children)
+            {
+                this.WalkTraceTreeForQueryMetrics(childTrace, ref queryMetrics);
+            }
+
+            return false;
+        }
+
         private bool WalkTraceTreeForGoneException(ITrace currentTrace)
         {
             if (currentTrace == null)

Microsoft.Azure.Cosmos/src/Query/Core/Metrics/BackendAccumulatedMetrics.cs

@@ -0,0 +1,140 @@
+//------------------------------------------------------------
+// Copyright (c) Microsoft Corporation.  All rights reserved.
+//------------------------------------------------------------
+namespace Microsoft.Azure.Cosmos
+{
+    using System;
+    using Microsoft.Azure.Cosmos.Query.Core.Metrics;
+
+    /// <summary>
+    /// Exposed metrics received for queries from the backend.
+    /// </summary>
+    public sealed class BackendAccumulatedMetrics
+    {
+        internal BackendAccumulatedMetrics(QueryMetrics queryMetrics)
+        {
+            this.RetrievedDocumentCount = queryMetrics.BackendMetrics.RetrievedDocumentCount;
+            this.RetrievedDocumentSize = queryMetrics.BackendMetrics.RetrievedDocumentSize;
+            this.OutputDocumentCount = queryMetrics.BackendMetrics.OutputDocumentCount;
+            this.OutputDocumentSize = queryMetrics.BackendMetrics.OutputDocumentSize;
+            this.IndexHitRatio = queryMetrics.BackendMetrics.IndexHitRatio;
+            this.TotalTime = queryMetrics.BackendMetrics.TotalTime;
+            this.QueryCompilationTime = queryMetrics.BackendMetrics.QueryPreparationTimes.QueryCompilationTime;
+            this.LogicalPlanBuildTime = queryMetrics.BackendMetrics.QueryPreparationTimes.LogicalPlanBuildTime;
+            this.PhysicalPlanBuildTime = queryMetrics.BackendMetrics.QueryPreparationTimes.PhysicalPlanBuildTime;
+            this.QueryOptimizationTime = queryMetrics.BackendMetrics.QueryPreparationTimes.QueryOptimizationTime;
+            this.IndexLookupTime = queryMetrics.BackendMetrics.IndexLookupTime;
+            this.DocumentLoadTime = queryMetrics.BackendMetrics.DocumentLoadTime;
+            this.VMExecutionTime = queryMetrics.BackendMetrics.VMExecutionTime;
+            this.SystemFunctionExecutionTime = queryMetrics.BackendMetrics.RuntimeExecutionTimes.SystemFunctionExecutionTime;
+            this.UserDefinedFunctionExecutionTime = queryMetrics.BackendMetrics.RuntimeExecutionTimes.UserDefinedFunctionExecutionTime;
+            this.QueryEngineExecutionTime = queryMetrics.BackendMetrics.RuntimeExecutionTimes.QueryEngineExecutionTime;
+            this.DocumentWriteTime = queryMetrics.BackendMetrics.DocumentWriteTime;
+        }
+
+        /// <summary>
+        /// Gets the total query time in the Azure Cosmos database service.
+        /// </summary>
+        public TimeSpan TotalTime { get; }
+
+        /// <summary>
+        /// Gets the query compile time in the Azure DocumentDB database service. 
+        /// </summary>
+        public TimeSpan QueryCompilationTime { get; }
+
+        /// <summary>
+        /// Gets the query logical plan build time in the Azure DocumentDB database service. 
+        /// </summary>
+        public TimeSpan LogicalPlanBuildTime { get; }
+
+        /// <summary>
+        /// Gets the query physical plan build time in the Azure DocumentDB database service. 
+        /// </summary>
+        public TimeSpan PhysicalPlanBuildTime { get; }
+
+        /// <summary>
+        /// Gets the query optimization time in the Azure DocumentDB database service. 
+        /// </summary>
+        public TimeSpan QueryOptimizationTime { get; }
+
+        /// <summary>
+        /// Gets the number of documents retrieved during query in the Azure Cosmos database service.
+        /// </summary>
+        public long RetrievedDocumentCount { get; }
+
+        /// <summary>
+        /// Gets the size of documents retrieved in bytes during query in the Azure Cosmos DB service.
+        /// </summary>
+        public long RetrievedDocumentSize { get; }
+
+        /// <summary>
+        /// Gets the number of documents returned by query in the Azure Cosmos DB service.
+        /// </summary>
+        public long OutputDocumentCount { get; }
+
+        /// <summary>
+        /// Gets the size of documents outputted in bytes during query in the Azure Cosmos database service.
+        /// </summary>
+        public long OutputDocumentSize { get; }
+
+        /// <summary>
+        /// Gets the query QueryPreparationTimes in the Azure Cosmos database service.
+        /// </summary>
+        public TimeSpan QueryPreparationTimes { get; }
+
+        /// <summary>
+        /// Gets the query index lookup time in the Azure Cosmos database service.
+        /// </summary>
+        public TimeSpan IndexLookupTime { get; }
+
+        /// <summary>
+        /// Gets the document loading time during query in the Azure Cosmos database service.
+        /// </summary>
+        public TimeSpan DocumentLoadTime { get; }
+
+        /// <summary>
+        /// Gets the query runtime execution times during query in the Azure Cosmos database service.
+        /// </summary>
+        public TimeSpan RuntimeExecutionTimes { get; }
+
+        /// <summary>
+        /// Gets the output writing/serializing time during query in the Azure Cosmos database service.
+        /// </summary>
+        public TimeSpan DocumentWriteTime { get; }
+
+        /// <summary>
+        /// Gets the index hit ratio by query in the Azure Cosmos database service.
+        /// </summary>
+        public double IndexHitRatio { get; }
+
+        /// <summary>
+        /// Gets the VMExecution Time.
+        /// </summary>
+        public TimeSpan VMExecutionTime { get; }
+
+        /// <summary>
+        /// Gets the query system function execution time in the Azure Cosmos DB service.
+        /// </summary>
+        public TimeSpan SystemFunctionExecutionTime { get; }
+
+        /// <summary>
+        /// Gets the query user defined function execution time in the Azure Cosmos DB service.
+        /// </summary>
+        public TimeSpan UserDefinedFunctionExecutionTime { get; }
+
+        /// <summary>
+        /// Gets the total query runtime execution time in the Azure Cosmos DB service.
+        /// </summary>
+        public TimeSpan QueryEngineExecutionTime { get; }
+
+        /// <summary>
+        /// String representation of the QueryBackendMetrics.
+        /// </summary>
+        /// <returns>Metric text</returns>
+        public override string ToString()
+        {
+            return $"totalExecutionTimeInMs={this.TotalTime.TotalMilliseconds};queryCompileTimeInMs={this.QueryCompilationTime.TotalMilliseconds};queryLogicalPlanBuildTimeInMs={this.LogicalPlanBuildTime.TotalMilliseconds};queryPhysicalPlanBuildTimeInMs={this.PhysicalPlanBuildTime.TotalMilliseconds};queryOptimizationTimeInMs={this.QueryOptimizationTime.TotalMilliseconds};indexLookupTimeInMs={this.IndexLookupTime.TotalMilliseconds};documentLoadTimeInMs={this.DocumentLoadTime.TotalMilliseconds};systemFunctionExecuteTimeInMs={this.SystemFunctionExecutionTime.TotalMilliseconds};userFunctionExecuteTimeInMs={this.UserDefinedFunctionExecutionTime.TotalMilliseconds};retrievedDocumentCount={this.RetrievedDocumentCount};retrievedDocumentSize={this.RetrievedDocumentSize};outputDocumentCount={this.OutputDocumentCount};outputDocumentSize={this.OutputDocumentSize};writeOutputTimeInMs={this.DocumentWriteTime.TotalMilliseconds};indexUtilizationRatio={this.IndexHitRatio}";
+        }
+
+    }
+}

Microsoft.Azure.Cosmos/src/Query/Core/Metrics/RuntimeExecutionTimes.cs

@@ -62,9 +62,9 @@ public Accumulator(TimeSpan queryEngineExecutionTime, TimeSpan systemFunctionExe
                 this.UserDefinedFunctionExecutionTime = userDefinedFunctionExecutionTimes;
             }
 
-            public TimeSpan QueryEngineExecutionTime { get; set; }
-            public TimeSpan SystemFunctionExecutionTime { get; set; }
-            public TimeSpan UserDefinedFunctionExecutionTime { get; set; }
+            public TimeSpan QueryEngineExecutionTime { get; }
+            public TimeSpan SystemFunctionExecutionTime { get; }
+            public TimeSpan UserDefinedFunctionExecutionTime { get; }
 
             public Accumulator Accumulate(RuntimeExecutionTimes runtimeExecutionTimes)
             {

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/Query/Metrics/BackendAccumulatedMetricsTests.cs

@@ -0,0 +1,13 @@
+namespace Microsoft.Azure.Cosmos.Tests.Query.Metrics
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Linq;
+    using System.Text;
+    using System.Threading.Tasks;
+
+    internal class BackendAccumulatedMetricsTests
+    {
+        //TODO
+    }
+}