Use a stronger session ID for editors than the process ID

kzu · kzu · commit dbf1cb075923 · 2024-07-09T02:12:15.000-03:00
In Visual Studio in particular, the build process can be performed by multiple processes simultaneously, yet they all share the same session identifier. Rider has a similar mechanism. Use that to signal the product-wide analyzer status, so that we reduce the chances of getting duplicate reports.
diff --git a/samples/dotnet/SponsorLink/DiagnosticsManager.cs b/samples/dotnet/SponsorLink/DiagnosticsManager.cs
@@ -56,10 +56,10 @@ public void ReportOnce(Action<Diagnostic> report, string product = Funding.Produ
         {
             // Ensure only one such diagnostic is reported per product for the entire process, 
             // so that we can avoid polluting the error list with duplicates across multiple projects.
-            var id = string.Concat(Process.GetCurrentProcess().Id, product, diagnostic.Id);
+            var id = string.Concat(SessionId, product, diagnostic.Id);
             using var mutex = new Mutex(false, "mutex" + id);
             mutex.WaitOne();
-            using var mmf = CreateOrOpenMemoryMappedFile(id, 1);
+            using var mmf = CreateOrOpenMemoryMappedFile(product, 1);
             using var accessor = mmf.CreateViewAccessor();
             if (accessor.ReadByte(0) == 0)
             {
@@ -177,7 +177,7 @@ Diagnostic Push(Diagnostic diagnostic, string product = Funding.Product)
         if (Diagnostics.TryAdd(product, diagnostic))
         {
             // Reset the process-wide flag for this diagnostic.
-            var id = string.Concat(Process.GetCurrentProcess().Id, product, diagnostic.Id);
+            var id = string.Concat(SessionId, product, diagnostic.Id);
             using var mutex = new Mutex(false, "mutex" + id);
             mutex.WaitOne();
             using var mmf = CreateOrOpenMemoryMappedFile(id, 1);
@@ -204,18 +204,14 @@ Diagnostic Push(Diagnostic diagnostic, string product = Funding.Product)
     static MemoryMappedFile CreateOrOpenMemoryMappedFile(string mapName, int capacity)
     {
         if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
-        {
             return MemoryMappedFile.CreateOrOpen(mapName, capacity);
-        }
-        else
-        {
-            // On Linux, use a file-based memory-mapped file
-            string filePath = $"/tmp/{mapName}";
-            using (var fs = new FileStream(filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite))
-                fs.Write(new byte[capacity], 0, capacity);
 
-            return MemoryMappedFile.CreateFromFile(filePath, FileMode.OpenOrCreate);
-        }
+        // On *nix, use a file-based memory-mapped file
+        var filePath = $"/tmp/{mapName}";
+        using (var fs = new FileStream(filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite))
+            fs.Write(new byte[capacity], 0, capacity);
+
+        return MemoryMappedFile.CreateFromFile(filePath, FileMode.OpenOrCreate);
     }
 
     internal static DiagnosticDescriptor CreateSponsor(string[] sponsorable, string prefix) => new(
diff --git a/samples/dotnet/SponsorLink/SponsorLink.cs b/samples/dotnet/SponsorLink/SponsorLink.cs
@@ -3,6 +3,7 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
+using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Linq;
@@ -43,6 +44,14 @@ static partial class SponsorLink
         Environment.GetEnvironmentVariable("RESHARPER_FUS_SESSION") != null ||
         Environment.GetEnvironmentVariable("IDEA_INITIAL_DIRECTORY") != null;
 
+    /// <summary>
+    /// A unique session ID associated with the current IDE or process running the analyzer.
+    /// </summary>
+    public static string SessionId => 
+        IsVisualStudio ? Environment.GetEnvironmentVariable("ServiceHubLogSessionKey") :
+        IsRider ? Environment.GetEnvironmentVariable("RESHARPER_FUS_SESSION") :
+        Process.GetCurrentProcess().Id.ToString();
+
     /// <summary>
     /// Manages the sharing and reporting of diagnostics across the source generator 
     /// and the diagnostic analyzer, to avoid doing the online check more than once.
