Bug 1613659 - Remove network listeners and reset TRR mode when enable…

…d pref is rolled back. r=dragana

Differential Revision: https://phabricator.services.mozilla.com/D61845

browser/extensions/doh-rollout/background.js

@@ -574,14 +574,6 @@ const rollout = {
 
 const setup = {
   async start() {
-    DEBUG = await browser.experiments.preferences.getBoolPref(
-      DOH_DEBUG_PREF,
-      false
-    );
-
-    // Run Migration First, to continue to run rest of start up logic
-    await rollout.migrateLocalStoragePrefs();
-
     const isAddonDisabled = await rollout.getSetting(DOH_DISABLED_PREF, false);
     const runAddonPref = await rollout.getSetting(DOH_ENABLED_PREF, false);
     const runAddonBypassPref = await rollout.getSetting(
@@ -617,21 +609,47 @@ const setup = {
     ) {
       rollout.init();
     } else {
-      log(
-        "Disabled, aborting! Watching `doh-rollout.enabled` pref for change event"
-      );
-      // Listen for changes to the enabled pref. TODO: Also listen after init
-      // and properly handle the value of enabled changing to false.
-      browser.experiments.preferences.onPrefChanged.addListener(
-        function listener() {
-          browser.experiments.preferences.onPrefChanged.removeListener(
-            listener
-          );
-          setup.start();
-        }
-      );
+      log("Disabled, aborting!");
     }
   },
 };
 
-setup.start();
+(async () => {
+  DEBUG = await browser.experiments.preferences.getBoolPref(
+    DOH_DEBUG_PREF,
+    false
+  );
+
+  // Run Migration First, to continue to run rest of start up logic
+  await rollout.migrateLocalStoragePrefs();
+
+  log("Watching `doh-rollout.enabled` pref");
+  browser.experiments.preferences.onPrefChanged.addListener(async () => {
+    let enabled = await rollout.getSetting(DOH_ENABLED_PREF, false);
+    if (enabled) {
+      setup.start();
+    } else {
+      // Reset the TRR mode if we were running normally with no user-interference.
+      if (await stateManager.shouldRunHeuristics()) {
+        await stateManager.setState("disabled");
+      }
+
+      // Remove our listeners.
+      browser.networkStatus.onConnectionChanged.removeListener(
+        rollout.onConnectionChanged
+      );
+
+      try {
+        browser.captivePortal.onStateChange.removeListener(
+          rollout.onCaptiveStateChanged
+        );
+      } catch (e) {
+        // Captive Portal Service is disabled.
+      }
+    }
+  });
+
+  if (await rollout.getSetting(DOH_ENABLED_PREF, false)) {
+    setup.start();
+  }
+})();

browser/extensions/doh-rollout/test/browser/browser.ini

@@ -8,4 +8,5 @@ skip-if = debug # Bug 1548006 - reloading an addon upsets the leak checker.
 [browser_doorhanger_newProfile.js]
 [browser_policyOverride.js]
 skip-if = (!debug && bits == 64) #Bug 1605297
+[browser_rollback.js]
 [browser_userInterference.js]

browser/extensions/doh-rollout/test/browser/browser_rollback.js

@@ -0,0 +1,110 @@
+"use strict";
+
+add_task(setup);
+
+add_task(async function testRollback() {
+  // Set up a passing environment and enable DoH.
+  setPassingHeuristics();
+  let promise = waitForDoorhanger();
+  Preferences.set(prefs.DOH_ENABLED_PREF, true);
+
+  await BrowserTestUtils.waitForCondition(() => {
+    return Preferences.get(prefs.DOH_SELF_ENABLED_PREF);
+  });
+  is(Preferences.get(prefs.DOH_SELF_ENABLED_PREF), true, "Breadcrumb saved.");
+
+  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, EXAMPLE_URL);
+  let panel = await promise;
+  is(
+    Preferences.get(prefs.DOH_DOORHANGER_SHOWN_PREF),
+    undefined,
+    "Doorhanger shown pref undefined before user interaction."
+  );
+
+  // Click the doorhanger's "accept" button.
+  let button = panel.querySelector(".popup-notification-primary-button");
+  promise = BrowserTestUtils.waitForEvent(panel, "popuphidden");
+  EventUtils.synthesizeMouseAtCenter(button, {});
+  await promise;
+
+  await ensureTRRMode(2);
+  await checkHeuristicsTelemetry("enable_doh", "startup");
+
+  await BrowserTestUtils.waitForCondition(() => {
+    return Preferences.get(prefs.DOH_DOORHANGER_SHOWN_PREF);
+  });
+  is(
+    Preferences.get(prefs.DOH_DOORHANGER_SHOWN_PREF),
+    true,
+    "Doorhanger shown pref saved."
+  );
+  is(
+    Preferences.get(prefs.DOH_DOORHANGER_USER_DECISION_PREF),
+    "UIOk",
+    "Doorhanger decision saved."
+  );
+  is(
+    Preferences.get(prefs.DOH_SELF_ENABLED_PREF),
+    true,
+    "Breadcrumb not cleared."
+  );
+
+  BrowserTestUtils.removeTab(tab);
+
+  // Change the environment to failing and simulate a network change.
+  setFailingHeuristics();
+  simulateNetworkChange();
+  await ensureTRRMode(0);
+  await checkHeuristicsTelemetry("disable_doh", "netchange");
+
+  // Trigger another network change.
+  simulateNetworkChange();
+  await ensureNoTRRModeChange(0);
+  await checkHeuristicsTelemetry("disable_doh", "netchange");
+
+  // Rollback!
+  setPassingHeuristics();
+  Preferences.reset(prefs.DOH_ENABLED_PREF);
+  await ensureTRRMode(0);
+  simulateNetworkChange();
+  await ensureNoTRRModeChange(0);
+  await ensureNoHeuristicsTelemetry();
+
+  // Re-enable.
+  Preferences.set(prefs.DOH_ENABLED_PREF, true);
+
+  await ensureTRRMode(2);
+  await checkHeuristicsTelemetry("enable_doh", "startup");
+
+  // Change the environment to failing and simulate a network change.
+  setFailingHeuristics();
+  simulateNetworkChange();
+  await ensureTRRMode(0);
+  await checkHeuristicsTelemetry("disable_doh", "netchange");
+
+  // Rollback again for good measure! This time with failing heuristics.
+  Preferences.reset(prefs.DOH_ENABLED_PREF);
+  await ensureTRRMode(0);
+  simulateNetworkChange();
+  await ensureNoTRRModeChange(0);
+  await ensureNoHeuristicsTelemetry();
+
+  // Re-enable.
+  Preferences.set(prefs.DOH_ENABLED_PREF, true);
+
+  await ensureNoTRRModeChange(0);
+  await checkHeuristicsTelemetry("disable_doh", "startup");
+
+  // Change the environment to passing and simulate a network change.
+  setPassingHeuristics();
+  simulateNetworkChange();
+  await ensureTRRMode(2);
+  await checkHeuristicsTelemetry("enable_doh", "netchange");
+
+  // Rollback again, this time with TRR mode set to 2 prior to doing so.
+  Preferences.reset(prefs.DOH_ENABLED_PREF);
+  await ensureTRRMode(0);
+  simulateNetworkChange();
+  await ensureNoTRRModeChange(0);
+  await ensureNoHeuristicsTelemetry();
+});