add test

Author: jack0x2

.gitlab/e2e_install_packages/windows.yml

@@ -249,5 +249,6 @@ new-e2e-installer-windows:
       - EXTRA_PARAMS: --run "TestAgentMSIInstallsDotnetLibrary/TestMSISkipRollbackIfInstalled$"
       - EXTRA_PARAMS: --run "TestAgentMSIInstallsDotnetLibrary/TestUninstallKeepsLibrary$"
       - EXTRA_PARAMS: --run "TestAgentMSIInstallsDotnetLibrary/TestUninstallScript$"
+      - EXTRA_PARAMS: --run "TestAgentMSIInstallsDotnetLibrary/TestMSIPurge$"
       - EXTRA_PARAMS: --run "TestAgentScriptInstallsDotnetLibrary/TestInstallFromScript$"
       - EXTRA_PARAMS: --run "TestAgentScriptInstallsDotnetLibrary/TestScriptThenRemoteUpgrade$"

test/new-e2e/tests/installer/windows/suites/apm-library-dotnet-package/msi_install_test.go

@@ -297,6 +297,44 @@ func (s *testAgentMSIInstallsDotnetLibrary) TestUninstallScript() {
 	s.Require().Empty(newLibraryPath)
 }
 
+// TestUninstallScript validates that instrumentation is disabled after we run the uninstall script
+func (s *testAgentMSIInstallsDotnetLibrary) TestMSIPurge() {
+	// Arrange
+	version := s.currentDotnetLibraryVersion
+
+	// Act
+	s.installCurrentAgentVersion(
+		installerwindows.WithMSIArg("DD_APM_INSTRUMENTATION_ENABLED=iis"),
+		// TODO: remove override once image is published in prod
+		installerwindows.WithMSIArg("DD_INSTALLER_REGISTRY_URL=install.datad0g.com.internal.dda-testing.com"),
+		installerwindows.WithMSIArg(fmt.Sprintf("DD_APM_INSTRUMENTATION_LIBRARIES=dotnet:%s", version.PackageVersion())),
+		installerwindows.WithMSILogFile("install.log"),
+	)
+	// Start the IIS app to load the library
+	defer s.stopIISApp()
+	s.startIISApp(webConfigFile, aspxFile)
+
+	// Assert
+	s.assertSuccessfulPromoteExperiment(version.Version())
+	// Check that the expected version of the library is loaded
+	oldLibraryPath := s.getLibraryPathFromInstrumentedIIS()
+	s.Require().Contains(oldLibraryPath, version.Version())
+
+	// uninstall the MSI with PURGE=1
+	options := []installerwindows.MsiOption{
+		installerwindows.WithMSILogFile("uninstall.log"),
+		installerwindows.WithMSIArg("PURGE=1"),
+	}
+	s.Require().NoError(s.Installer().Uninstall(options...))
+
+	// verify it is uninstalled
+	s.stopIISApp()
+	defer s.stopIISApp()
+	s.startIISApp(webConfigFile, aspxFile)
+	newLibraryPath := s.getLibraryPathFromInstrumentedIIS()
+	s.Require().Empty(newLibraryPath)
+}
+
 func (s *testAgentMSIInstallsDotnetLibrary) installPreviousAgentVersion(opts ...installerwindows.MsiOption) {
 	agentVersion := s.StableAgentVersion().Version()
 	options := []installerwindows.MsiOption{