Bug 1616052 - Add low-level helpers to debug and test Remote Settings r=tarek,glasserc

Differential Revision: https://phabricator.services.mozilla.com/D63207

--HG--
extra : moz-landing-system : lando

services/common/docs/RemoteSettings.rst

@@ -142,7 +142,6 @@ The provided helper will:
 
     The following aspects are not taken care of (yet! help welcome):
 
-    - report Telemetry when download fails
     - check available disk space
     - preserve bandwidth
     - resume downloads of large files
@@ -295,6 +294,12 @@ The synchronization of every known remote settings clients can be triggered manu
 
     await RemoteSettings.pollChanges()
 
+In order to ignore last synchronization status during polling for changes, set the ``full`` option:
+
+.. code-block:: js
+
+    await RemoteSettings.pollChanges({ full: true })
+
 The synchronization of a single client can be forced with the ``.sync()`` method:
 
 .. code-block:: js
@@ -314,6 +319,16 @@ The internal IndexedDB of Remote Settings can be accessed via the Storage Inspec
 For example, the local data of the ``"key"`` collection can be accessed in the ``remote-settings`` database at *Browser Toolbox* > *Storage* > *IndexedDB* > *chrome*, in the ``records`` store.
 
 
+Delete all local data
+---------------------
+
+All local data, of **every collection**, including downloaded attachments, can be deleted with:
+
+.. code-block:: js
+
+    await RemoteSettings.clearAll();
+
+
 Unit Tests
 ==========
 

services/settings/RemoteSettingsClient.jsm

@@ -171,6 +171,21 @@ class AttachmentDownloader extends Downloader {
       throw err;
     }
   }
+
+  /**
+   * Delete all downloaded records attachments.
+   *
+   * Note: the list of attachments to be deleted is based on the
+   * current list of records.
+   */
+  async deleteAll() {
+    const kintoCol = await this._client.openCollection();
+    const { data: allRecords } = await kintoCol.list();
+    await kintoCol.db.close();
+    return Promise.all(
+      allRecords.filter(r => !!r.attachment).map(r => this.delete(r))
+    );
+  }
 }
 
 class RemoteSettingsClient extends EventEmitter {
@@ -263,7 +278,6 @@ class RemoteSettingsClient extends EventEmitter {
    */
   async getLastModified() {
     let timestamp = -1;
-
     try {
       const collection = await this.openCollection();
       timestamp = await collection.db.getLastModified();

services/settings/remote-settings.js

@@ -17,31 +17,15 @@ const { XPCOMUtils } = ChromeUtils.import(
   "resource://gre/modules/XPCOMUtils.jsm"
 );
 
-ChromeUtils.defineModuleGetter(
-  this,
-  "UptakeTelemetry",
-  "resource://services-common/uptake-telemetry.js"
-);
-ChromeUtils.defineModuleGetter(
-  this,
-  "pushBroadcastService",
-  "resource://gre/modules/PushBroadcastService.jsm"
-);
-ChromeUtils.defineModuleGetter(
-  this,
-  "RemoteSettingsClient",
-  "resource://services-settings/RemoteSettingsClient.jsm"
-);
-ChromeUtils.defineModuleGetter(
-  this,
-  "Utils",
-  "resource://services-settings/Utils.jsm"
-);
-ChromeUtils.defineModuleGetter(
-  this,
-  "FilterExpressions",
-  "resource://gre/modules/components-utils/FilterExpressions.jsm"
-);
+XPCOMUtils.defineLazyModuleGetters(this, {
+  UptakeTelemetry: "resource://services-common/uptake-telemetry.js",
+  pushBroadcastService: "resource://gre/modules/PushBroadcastService.jsm",
+  RemoteSettingsClient: "resource://services-settings/RemoteSettingsClient.jsm",
+  Utils: "resource://services-settings/Utils.jsm",
+  FilterExpressions:
+    "resource://gre/modules/components-utils/FilterExpressions.jsm",
+  RemoteSettingsWorker: "resource://services-settings/RemoteSettingsWorker.jsm",
+});
 
 XPCOMUtils.defineLazyGlobalGetters(this, ["fetch"]);
 
@@ -171,12 +155,21 @@ function remoteSettingsFunction() {
    * @param {Object} options
 .  * @param {Object} options.expectedTimestamp (optional) The expected timestamp to be received — used by servers for cache busting.
    * @param {string} options.trigger           (optional) label to identify what triggered this sync (eg. ``"timer"``, default: `"manual"`)
+   * @param {bool}   options.full              (optional) Ignore last polling status and fetch all changes (default: `false`)
    * @returns {Promise} or throws error if something goes wrong.
    */
   remoteSettings.pollChanges = async ({
     expectedTimestamp,
     trigger = "manual",
+    full = false,
   } = {}) => {
+    // When running in full mode, we ignore last polling status.
+    if (full) {
+      gPrefs.clearUserPref(PREF_SETTINGS_SERVER_BACKOFF);
+      gPrefs.clearUserPref(PREF_SETTINGS_LAST_UPDATE);
+      gPrefs.clearUserPref(PREF_SETTINGS_LAST_ETAG);
+    }
+
     let pollTelemetryArgs = {
       source: TELEMETRY_SOURCE_POLL,
       trigger,
@@ -419,6 +412,26 @@ function remoteSettingsFunction() {
     };
   };
 
+  /**
+   * Delete all local data, of every collection.
+   */
+  remoteSettings.clearAll = async () => {
+    const { collections } = await remoteSettings.inspect();
+    await Promise.all(
+      collections.map(async ({ collection }) => {
+        const client = RemoteSettings(collection);
+        // Delete all potential attachments.
+        await client.attachments.deleteAll();
+        // Delete local data.
+        const kintoCollection = await client.openCollection();
+        await kintoCollection.clear();
+        await kintoCollection.db.close();
+        // Remove status pref.
+        Services.prefs.clearUserPref(client.lastCheckTimePref);
+      })
+    );
+  };
+
   /**
    * Startup function called from nsBrowserGlue.
    */

services/settings/test/unit/test_attachments_downloader.js

@@ -196,6 +196,20 @@ add_task(async function test_delete_removes_local_file() {
 });
 add_task(clear_state);
 
+add_task(async function test_delete_all() {
+  const client = RemoteSettings("some-collection");
+  const kintoCol = await client.openCollection();
+  await kintoCol.create(RECORD);
+  const fileURL = await downloader.download(RECORD);
+  const localFilePath = pathFromURL(fileURL);
+  Assert.ok(await OS.File.exists(localFilePath));
+
+  await client.attachments.deleteAll();
+
+  Assert.ok(!(await OS.File.exists(localFilePath)));
+});
+add_task(clear_state);
+
 add_task(async function test_downloader_is_accessible_via_client() {
   const client = RemoteSettings("some-collection");
 

services/settings/test/unit/test_remote_settings.js

@@ -269,6 +269,7 @@ add_task(async function test_get_does_not_sync_if_empty_dump_is_provided() {
   equal(data.length, 0);
   Assert.ok(await Utils.hasLocalData(clientWithEmptyDump));
 });
+add_task(clear_state);
 
 add_task(async function test_get_synchronization_can_be_disabled() {
   const data = await client.get({ syncIfEmpty: false });
@@ -501,6 +502,28 @@ add_task(async function test_inspect_method() {
 });
 add_task(clear_state);
 
+add_task(async function test_clearAll_method() {
+  // Make sure we have some local data.
+  await client.maybeSync(2000);
+  await clientWithDump.maybeSync(2000);
+
+  await RemoteSettings.clearAll();
+
+  ok(!(await Utils.hasLocalData(client)), "Local data was deleted");
+  ok(!(await Utils.hasLocalData(clientWithDump)), "Local data was deleted");
+  ok(
+    !Services.prefs.prefHasUserValue(client.lastCheckTimePref),
+    "Pref was cleaned"
+  );
+
+  // Synchronization is not broken after resuming.
+  await client.maybeSync(2000);
+  await clientWithDump.maybeSync(2000);
+  ok(await Utils.hasLocalData(client), "Local data was populated");
+  ok(await Utils.hasLocalData(clientWithDump), "Local data was populated");
+});
+add_task(clear_state);
+
 add_task(async function test_listeners_are_not_deduplicated() {
   let count = 0;
   const plus1 = () => {

services/settings/test/unit/test_remote_settings_poll.js

@@ -538,6 +538,34 @@ add_task(async function test_success_with_partial_list() {
 });
 add_task(clear_state);
 
+add_task(async function test_full_polling() {
+  server.registerPathHandler(
+    CHANGES_PATH,
+    serveChangesEntries(10000, [
+      {
+        id: "b6ba7fab-a40a-4d03-a4af-6b627f3c5b36",
+        last_modified: 42,
+        host: "localhost",
+        bucket: "main",
+        collection: "poll-test-collection",
+      },
+    ])
+  );
+
+  const c = RemoteSettings("poll-test-collection");
+  let maybeSyncCount = 0;
+  c.maybeSync = () => {
+    maybeSyncCount++;
+  };
+
+  await RemoteSettings.pollChanges();
+  await RemoteSettings.pollChanges({ full: true });
+
+  // Since the second call is full, clients are called
+  Assert.equal(maybeSyncCount, 2, "maybeSync should be called twice");
+});
+add_task(clear_state);
+
 add_task(async function test_server_bad_json() {
   const startHistogram = getUptakeTelemetrySnapshot(
     TELEMETRY_HISTOGRAM_POLL_KEY