Allow IScopeObserver to observe trace (#4026)

Author: bitsandfoxes

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Features
 
+- The `IScopeObserver` now has an `SetTrace` that allows observing changes to the scope's trace context. The SDK uses this to propagate the `trace ID` to `sentry-native`. This allows Sentry to connect errors coming from all layers of your application ([#4026](https://github.com/getsentry/sentry-dotnet/pull/4026))
 - Exception.HResult is now included in the mechanism data for all exceptions ([#4029](https://github.com/getsentry/sentry-dotnet/pull/4029))
 
 ### Fixes

src/Sentry/IScopeObserver.cs

@@ -29,4 +29,9 @@ public interface IScopeObserver
     /// Sets the user information.
     /// </summary>
     public void SetUser(SentryUser? user);
+
+    /// <summary>
+    /// Sets the current trace
+    /// </summary>
+    public void SetTrace(SentryId traceId, SpanId parentSpanId);
 }

src/Sentry/Internal/Hub.cs

@@ -255,7 +255,7 @@ public TransactionContext ContinueTrace(
         string? operation = null)
     {
         var propagationContext = SentryPropagationContext.CreateFromHeaders(_options.DiagnosticLogger, traceHeader, baggageHeader);
-        ConfigureScope(scope => scope.PropagationContext = propagationContext);
+        ConfigureScope(scope => scope.SetPropagationContext(propagationContext));
 
         return new TransactionContext(
             name: name ?? string.Empty,

src/Sentry/Internal/ScopeObserver.cs

@@ -84,4 +84,14 @@ public void SetUser(SentryUser? user)
     public abstract void SetUserImpl(SentryUser user);
 
     public abstract void UnsetUserImpl();
+
+    public void SetTrace(SentryId traceId, SpanId parentSpanId)
+    {
+        _options.DiagnosticLogger?.Log(
+            SentryLevel.Debug, "{0} Scope Sync - Setting Trace traceId:{1} parentSpanId:{2}", null,
+                _name, traceId, parentSpanId);
+        SetTraceImpl(traceId, parentSpanId);
+    }
+
+    public abstract void SetTraceImpl(SentryId traceId, SpanId parentSpanId);
 }

src/Sentry/Platforms/Android/AndroidScopeObserver.cs

@@ -99,4 +99,9 @@ public void SetUser(SentryUser? user)
             _innerObserver?.SetUser(user);
         }
     }
+
+    public void SetTrace(SentryId traceId, SpanId parentSpanId)
+    {
+        // TODO: This requires sentry-java 8.4.0
+    }
 }

src/Sentry/Platforms/Cocoa/CocoaScopeObserver.cs

@@ -107,4 +107,9 @@ public void SetUser(SentryUser? user)
             _innerObserver?.SetUser(user);
         }
     }
+
+    public void SetTrace(SentryId traceId, SpanId parentSpanId)
+    {
+        // TODO: Missing corresponding functionality on the Cocoa SDK
+    }
 }

src/Sentry/Platforms/Native/CFunctions.cs

@@ -241,6 +241,9 @@ internal static string GetCacheDirectory(SentryOptions options)
     [DllImport("sentry-native")]
     internal static extern void sentry_remove_extra(string key);
 
+    [DllImport("sentry-native")]
+    internal static extern void sentry_set_trace(string traceId, string parentSpanId);
+
     internal static Dictionary<long, DebugImage> LoadDebugImages(IDiagnosticLogger? logger)
     {
         // It only makes sense to load them once because they're cached on the native side anyway. We could force

src/Sentry/Platforms/Native/NativeScopeObserver.cs

@@ -40,6 +40,9 @@ public override void SetUserImpl(SentryUser user)
 
     public override void UnsetUserImpl() => C.sentry_remove_user();
 
+    public override void SetTraceImpl(SentryId traceId, SpanId parentSpanId) =>
+        C.sentry_set_trace(traceId.ToString(), parentSpanId.ToString());
+
     private static string GetTimestamp(DateTimeOffset timestamp) =>
         // "o": Using ISO 8601 to make sure the timestamp makes it to the bridge correctly.
         // https://docs.microsoft.com/en-gb/dotnet/standard/base-types/standard-date-and-time-format-strings#Roundtrip

src/Sentry/Scope.cs

@@ -233,7 +233,7 @@ public ITransactionTracer? Transaction
         }
     }
 
-    internal SentryPropagationContext PropagationContext { get; set; }
+    internal SentryPropagationContext PropagationContext { get; private set; }
 
     internal SessionUpdate? SessionUpdate { get; set; }
 
@@ -376,6 +376,15 @@ public void UnsetTag(string key)
     /// </summary>
     public void AddAttachment(SentryAttachment attachment) => _attachments.Add(attachment);
 
+    internal void SetPropagationContext(SentryPropagationContext propagationContext)
+    {
+        PropagationContext = propagationContext;
+        if (Options.EnableScopeSync)
+        {
+            Options.ScopeObserver?.SetTrace(propagationContext.TraceId, propagationContext.SpanId);
+        }
+    }
+
     /// <summary>
     /// Resets all the properties and collections within the scope to their default values.
     /// </summary>

src/Sentry/Sentry.csproj

@@ -16,8 +16,14 @@
 
   <PropertyGroup Condition="'$(SolutionName)' == 'Sentry.Unity'">
     <TargetFrameworks>netstandard2.0;netstandard2.1</TargetFrameworks>
+    <!-- To be able to make the internals visible, since we're not signing the assembly for Unity -->
+    <SignAssembly>false</SignAssembly>
   </PropertyGroup>
 
+  <ItemGroup Condition="'$(SolutionName)' == 'Sentry.Unity'">
+    <InternalsVisibleTo Include="Sentry.Unity" />
+  </ItemGroup>
+
   <!-- Platform-specific props included here -->
   <Import Project="Platforms\Android\Sentry.Android.props" Condition="'$(TargetPlatformIdentifier)' == 'android'" />
   <Import Project="Platforms\Cocoa\Sentry.Cocoa.props" Condition="'$(TargetPlatformIdentifier)' == 'ios' Or '$(TargetPlatformIdentifier)' == 'maccatalyst'" />