Chromium trace file format exporter

src/PerfView/StackViewer/StackWindow.xaml.cs

@@ -898,7 +898,7 @@ internal void DoSave(object sender, RoutedEventArgs e)
                 saveDialog.InitialDirectory = Path.GetDirectoryName(DataSource.FilePath);
                 saveDialog.Title = "File to save view";
                 saveDialog.DefaultExt = ".perfView.xml.zip";
-                saveDialog.Filter = "PerfView view file|*.perfView.xml.zip|Comma Separated Value|*.csv|Speed Scope Format|*.speedscope.json|All Files|*.*";
+                saveDialog.Filter = "PerfView view file|*.perfView.xml.zip|Comma Separated Value|*.csv|Speed Scope|*.speedscope.json|Chromium Trace Event|*.chromium.json|All Files|*.*";
                 saveDialog.AddExtension = true;
                 saveDialog.OverwritePrompt = true;
 
@@ -948,6 +948,10 @@ internal void DoSave(object sender, RoutedEventArgs e)
             {
                 SpeedScopeStackSourceWriter.WriteStackViewAsJson(CallTree.StackSource, m_fileName);
             }
+            else if (m_fileName.EndsWith(".chromium.json", StringComparison.OrdinalIgnoreCase))
+            {
+                ChromiumStackSourceWriter.WriteStackViewAsJson(CallTree.StackSource, m_fileName, false);
+            }
             else
             {
                 if (m_fileName.EndsWith(".xml", StringComparison.OrdinalIgnoreCase))

src/TraceEvent/Stacks/ChromiumStackSourceWriter.cs

@@ -0,0 +1,106 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.IO.Compression;
+using System.Linq;
+using static Microsoft.Diagnostics.Tracing.Stacks.StackSourceWriterHelper;
+
+namespace Microsoft.Diagnostics.Tracing.Stacks.Formats
+{
+    public class ChromiumStackSourceWriter
+    {
+        /// <summary>
+        /// exports provided StackSource to a Chromium Trace File format 
+        /// schema: https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU/
+        /// </summary>
+        public static void WriteStackViewAsJson(StackSource source, string filePath, bool compress)
+        {
+            if (compress && !filePath.EndsWith(".gz", StringComparison.OrdinalIgnoreCase))
+                filePath += ".gz";
+
+            if (File.Exists(filePath))
+                File.Delete(filePath);
+
+            using (var writeStream = compress ? (Stream)new GZipStream(File.Create(filePath), CompressionMode.Compress, leaveOpen: false) : File.Create(filePath))
+            using (var streamWriter = new StreamWriter(writeStream))
+            {
+                Export(source, streamWriter, Path.GetFileNameWithoutExtension(filePath));
+            }
+        }
+
+        #region private
+        private static void Export(StackSource source, TextWriter writer, string name)
+        {
+            var samplesPerThread = GetSortedSamplesPerThread(source);
+
+            var exportedFrameNameToExportedFrameId = new Dictionary<string, int>();
+            var exportedFrameIdToFrameTuple = new Dictionary<int, FrameInfo>();
+            var profileEventsPerThread = new Dictionary<ThreadInfo, IReadOnlyList<ProfileEvent>>();
+
+            foreach (var pair in samplesPerThread)
+            {
+                var frameIdToSamples = WalkTheStackAndExpandSamples(source, pair.Value, exportedFrameNameToExportedFrameId, exportedFrameIdToFrameTuple);
+
+                var sortedProfileEvents = GetAggregatedOrderedProfileEvents(frameIdToSamples);
+
+                profileEventsPerThread.Add(pair.Key, sortedProfileEvents);
+            };
+
+            WriteToFile(exportedFrameIdToFrameTuple, profileEventsPerThread, writer, name);
+        }
+
+        private static void WriteToFile(Dictionary<int, FrameInfo> frameIdToFrameTuple,
+            IReadOnlyDictionary<ThreadInfo, IReadOnlyList<ProfileEvent>> sortedProfileEventsPerThread,
+            TextWriter writer, string name)
+        {
+            writer.Write("{");
+            writer.Write("\"traceEvents\": [");
+            bool isFirst = true;
+            foreach (var perThread in sortedProfileEventsPerThread.OrderBy(pair => pair.Value.First().RelativeTime))
+            {
+                foreach (var profileEvent in perThread.Value)
+                {
+                    if (!isFirst)
+                        writer.Write(", ");
+                    else
+                        isFirst = false;
+
+                    writer.Write("{");
+                    writer.Write($"\"name\": \"{frameIdToFrameTuple[profileEvent.FrameId].Name}\", ");
+                    writer.Write($"\"cat\": \"sampleEvent\", ");
+                    writer.Write($"\"ph\": \"{(profileEvent.Type == ProfileEventType.Open ? "B" : "E")}\", ");
+                    writer.Write($"\"ts\": {profileEvent.RelativeTime.ToString("R", CultureInfo.InvariantCulture)}, ");
+                    writer.Write($"\"pid\": {perThread.Key.ProcessId}, ");
+                    writer.Write($"\"tid\": {perThread.Key.Id}, ");
+                    writer.Write($"\"sf\": {profileEvent.FrameId}");
+                    writer.Write("}");
+                }
+            }
+            writer.Write("], ");
+            writer.Write("\"displayTimeUnit\": \"ms\", ");
+            writer.Write("\"stackFrames\": {");
+            isFirst = true;
+            foreach (var frame in frameIdToFrameTuple)
+            {
+                if (!isFirst)
+                    writer.Write(", ");
+                else
+                    isFirst = false;
+
+                var frameId = frame.Key;
+                var frameInfo = frame.Value;
+                writer.Write($"\"{frameId}\": {{");
+                writer.Write($"\"name\": \"{frameInfo.Name}\", ");
+                writer.Write($"\"category\": \"{frameInfo.Category}\"");
+                if (frameInfo.ParentId != -1)
+                    writer.Write($", \"parent\": {frameInfo.ParentId}");
+                writer.Write("}");
+            }
+            writer.Write("}, ");
+            writer.Write($"\"otherData\": {{ \"name\": \"{name}\" }}");
+            writer.Write("}");
+        }
+        #endregion private
+    }
+}