Closes #3877: Beta Uplift: Recover when content process gets killed (10022f2f) · Commits · The Tor Project / Applications / android-components

components/browser/engine-gecko-beta/src/main/java/mozilla/components/browser/engine/gecko/GeckoEngineSession.kt

+25 −2

Original line number	Diff line number	Diff line
		@@ -495,12 +495,35 @@ class GeckoEngineSession(
		override fun onCrash(session: GeckoSession) {
		stateBeforeCrash = lastSessionState

		geckoSession.close()
		createGeckoSession()
		recoverGeckoSession()

		notifyObservers { onCrash() }
		}

		override fun onKill(session: GeckoSession) {
		// The content process of this session got killed (resources reclaimed by Android).
		// Let's recover and restore the last known state.

		val state = lastSessionState

		recoverGeckoSession()

		state?.let { geckoSession.restoreState(it) }

		notifyObservers { onProcessKilled() }
		}

		private fun recoverGeckoSession() {
		// Recover the GeckoSession after the process getting killed or crashing. We create a
		// new underlying GeckoSession.
		// Eventually we may be able to re-use the same GeckoSession by re-opening it. However
		// that seems to have caused issues:
		// https://github.com/mozilla-mobile/android-components/issues/3640

		geckoSession.close()
		createGeckoSession()
		}

		override fun onFullScreen(session: GeckoSession, fullScreen: Boolean) {
		notifyObservers { onFullScreenChange(fullScreen) }
		}

+5 −0

Original line number	Diff line number	Diff line
		@@ -44,6 +44,11 @@ class GeckoEngineView @JvmOverloads constructor(
		override fun onCrash() {
		rebind()
		}

		override fun onProcessKilled() {
		rebind()
		}

		override fun onAppPermissionRequest(permissionRequest: PermissionRequest) = Unit
		override fun onContentPermissionRequest(permissionRequest: PermissionRequest) = Unit
		}

+26 −0

Original line number	Diff line number	Diff line
		@@ -1795,6 +1795,32 @@ class GeckoEngineSessionTest {
		assertEquals(LoadUrlFlags.BYPASS_CLASSIFIER, GeckoSession.LOAD_FLAGS_BYPASS_CLASSIFIER)
		}

		@Test
		fun `onKill will recover, restore state and notify observers`() {
		val engineSession = GeckoEngineSession(mock(),
		geckoSessionProvider = geckoSessionProvider)

		captureDelegates()

		var observerNotified = false

		engineSession.register(object : EngineSession.Observer {
		override fun onProcessKilled() {
		observerNotified = true
		}
		})

		val mockedState: GeckoSession.SessionState = mock()
		progressDelegate.value.onSessionStateChange(geckoSession, mockedState)

		verify(geckoSession, never()).restoreState(mockedState)

		contentDelegate.value.onKill(geckoSession)

		verify(geckoSession).restoreState(mockedState)
		assertTrue(observerNotified)
		}

		private fun mockGeckoSession(): GeckoSession {
		val session = mock<GeckoSession>()
		whenever(session.settings).thenReturn(

+22 −2

Original line number	Diff line number	Diff line
		@@ -15,8 +15,8 @@ import org.junit.Assert.assertNotNull
		import org.junit.Assert.assertNull
		import org.junit.Test
		import org.junit.runner.RunWith
		import org.mockito.Mockito
		import org.mockito.Mockito.never
		import org.mockito.Mockito.reset
		import org.mockito.Mockito.times
		import org.mockito.Mockito.verify
		import org.mozilla.geckoview.GeckoResult
		@@ -106,6 +106,26 @@ class GeckoEngineViewTest {
		verify(engineSession).unregister(any())
		}

		@Test
		fun `View will rebind session if process gets killed`() {
		val engineView = GeckoEngineView(context)
		val engineSession = mock<GeckoEngineSession>()
		val geckoSession = mock<GeckoSession>()
		val geckoView = mock<NestedGeckoView>()

		whenever(engineSession.geckoSession).thenReturn(geckoSession)
		engineView.currentGeckoView = geckoView

		engineView.render(engineSession)

		reset(geckoView)
		verify(geckoView, never()).setSession(geckoSession)

		engineView.observer.onProcessKilled()

		verify(geckoView).setSession(geckoSession)
		}

		@Test
		fun `View will rebind session if session crashed`() {
		val engineView = GeckoEngineView(context)
		@@ -118,7 +138,7 @@ class GeckoEngineViewTest {

		engineView.render(engineSession)

		Mockito.reset(geckoView)
		reset(geckoView)
		verify(geckoView, never()).setSession(geckoSession)

		engineView.observer.onCrash()

+3 −0

Original line number	Diff line number	Diff line
		@@ -15,6 +15,9 @@ permalink: /changelog/
		* support-test
		* Fixed [#3893](https://github.com/mozilla-mobile/android-components/issues/3893) Moving WebserverRule to support-test.

		* browser-engine-gecko-beta
		* The component now handles situations where the Android system kills the content process (without killing the main app process) in order to reclaim resources. In those situations the component will automatically recover and restore the last known state of those sessions.

		# 7.0.0

		* [Commits](https://github.com/mozilla-mobile/android-components/compare/v6.0.2...v7.0.0)