fix: HTTP transport on Mono with high stripping

.github/workflows/test-build-windows-mono.yml

@@ -77,14 +77,9 @@ jobs:
       - name: Add Sentry to the project
         run: ./test/Scripts.Integration.Test/add-sentry.ps1 -UnityPath "$env:UNITY_PATH" -PackagePath "test-package-release"
 
-      - name: Download DependencyConflict package
-        uses: ./.github/actions/wait-for-artifact
-        with:
-          name: dependency-conflict-package
-          path: dependency-conflict-package
-
-      - name: Add DependencyConflict to the project
-        run: ./test/Scripts.Integration.Test/add-dependency-conflict.ps1 -PackagePath "dependency-conflict-package"
+      # The package's unaliased System.Text.Json throws a FieldAccessException on Mono with High stripping.
+      - name: Disable DependencyConflict
+        run: ./test/Scripts.Integration.Test/add-dependency-conflict.ps1 -Disable
 
       - name: Configure Sentry
         run: ./test/Scripts.Integration.Test/configure-sentry.ps1 -UnityPath "$env:UNITY_PATH" -Platform Windows

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Fixes
+
+- The SDK now preserves the types Mono's HTTP stack needs, so events are sent when using `Mono` with a high managed stripping level ([#2858](https://github.com/getsentry/sentry-unity/pull/2858))
+
 ### Dependencies
 
 - Bump .NET SDK from v6.10.0 to v6.11.0 ([#2850](https://github.com/getsentry/sentry-unity/pull/2850))

src/Sentry.Unity.Editor/MonoLinkerProcessor.cs

@@ -0,0 +1,42 @@
+using System.IO;
+using UnityEditor;
+using UnityEditor.Build;
+using UnityEditor.Build.Reporting;
+using UnityEditor.UnityLinker;
+
+namespace Sentry.Unity.Editor;
+
+/// <summary>
+/// On Mono, `HttpWebRequest` initializes the configuration system, which creates its host and the `machine.config`
+/// section types via reflection. The UnityLinker can't see that and strips them on higher stripping levels, breaking
+/// the HTTP transport. Unity ignores `link.xml` files inside packages, so we provide the rules at build time instead.
+/// </summary>
+internal class MonoLinkerProcessor : IUnityLinkerProcessor
+{
+    internal const string LinkXml =
+        """
+        <linker>
+          <assembly fullname="System.Configuration">
+            <type fullname="System.Configuration.ExeConfigurationHost" preserve="all"/>
+          </assembly>
+          <assembly fullname="System">
+            <namespace fullname="System.Net.Configuration" preserve="all"/>
+          </assembly>
+        </linker>
+        """;
+
+    public int callbackOrder => 0;
+
+    public string? GenerateAdditionalLinkXmlFile(BuildReport report, UnityLinkerBuildPipelineData data)
+    {
+        var namedBuildTarget = NamedBuildTarget.FromBuildTargetGroup(report.summary.platformGroup);
+        if (PlayerSettings.GetScriptingBackend(namedBuildTarget) != ScriptingImplementation.Mono2x)
+        {
+            return null;
+        }
+
+        var path = Path.Combine(data.inputDirectory, "Sentry.Unity.link.xml");
+        File.WriteAllText(path, LinkXml);
+        return path;
+    }
+}

test/IntegrationTest/CommonTestCases.ps1

@@ -28,6 +28,10 @@ $CommonTestCases = @(
                 Set-ItResult -Skipped -Because "DependencyConflict is not installed on Unity 2021 + WebGL"
                 return
             }
+            if ($env:SENTRY_TEST_SCRIPTING_BACKEND -eq "mono") {
+                Set-ItResult -Skipped -Because "DependencyConflict is not installed on Mono"
+                return
+            }
 
             $RunResult.Output | Where-Object { $_ -match "DependencyConflict: FAILED" } |
                 Should -BeNullOrEmpty -Because "the DependencyConflict package threw at runtime - assembly aliasing likely regressed"