1 files changed, 193 insertions, 0 deletions
diff --git a/services/fxaccounts/FxAccountsProfile.sys.mjs b/services/fxaccounts/FxAccountsProfile.sys.mjs
new file mode 100644
index 0000000000..de8bdb2f0e
--- /dev/null
+++ b/services/fxaccounts/FxAccountsProfile.sys.mjs
@@ -0,0 +1,193 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Firefox Accounts Profile helper.
+ *
+ * This class abstracts interaction with the profile server for an account.
+ * It will handle things like fetching profile data, listening for updates to
+ * the user's profile in open browser tabs, and cacheing/invalidating profile data.
+ */
+
+import {
+  ON_PROFILE_CHANGE_NOTIFICATION,
+  log,
+} from "resource://gre/modules/FxAccountsCommon.sys.mjs";
+
+import { getFxAccountsSingleton } from "resource://gre/modules/FxAccounts.sys.mjs";
+
+const fxAccounts = getFxAccountsSingleton();
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  FxAccountsProfileClient:
+    "resource://gre/modules/FxAccountsProfileClient.sys.mjs",
+});
+
+export var FxAccountsProfile = function (options = {}) {
+  this._currentFetchPromise = null;
+  this._cachedAt = 0; // when we saved the cached version.
+  this._isNotifying = false; // are we sending a notification?
+  this.fxai = options.fxai || fxAccounts._internal;
+  this.client =
+    options.profileClient ||
+    new lazy.FxAccountsProfileClient({
+      fxai: this.fxai,
+      serverURL: options.profileServerUrl,
+    });
+
+  // An observer to invalidate our _cachedAt optimization. We use a weak-ref
+  // just incase this.tearDown isn't called in some cases.
+  Services.obs.addObserver(this, ON_PROFILE_CHANGE_NOTIFICATION, true);
+  // for testing
+  if (options.channel) {
+    this.channel = options.channel;
+  }
+};
+
+FxAccountsProfile.prototype = {
+  // If we get subsequent requests for a profile within this period, don't bother
+  // making another request to determine if it is fresh or not.
+  PROFILE_FRESHNESS_THRESHOLD: 120000, // 2 minutes
+
+  observe(subject, topic, data) {
+    // If we get a profile change notification from our webchannel it means
+    // the user has just changed their profile via the web, so we want to
+    // ignore our "freshness threshold"
+    if (topic == ON_PROFILE_CHANGE_NOTIFICATION && !this._isNotifying) {
+      log.debug("FxAccountsProfile observed profile change");
+      this._cachedAt = 0;
+    }
+  },
+
+  tearDown() {
+    this.fxai = null;
+    this.client = null;
+    Services.obs.removeObserver(this, ON_PROFILE_CHANGE_NOTIFICATION);
+  },
+
+  _notifyProfileChange(uid) {
+    this._isNotifying = true;
+    Services.obs.notifyObservers(null, ON_PROFILE_CHANGE_NOTIFICATION, uid);
+    this._isNotifying = false;
+  },
+
+  // Cache fetched data and send out a notification so that UI can update.
+  _cacheProfile(response) {
+    return this.fxai.withCurrentAccountState(async state => {
+      const profile = response.body;
+      const userData = await state.getUserAccountData();
+      if (profile.uid != userData.uid) {
+        throw new Error(
+          "The fetched profile does not correspond with the current account."
+        );
+      }
+      let profileCache = {
+        profile,
+        etag: response.etag,
+      };
+      await state.updateUserAccountData({ profileCache });
+      if (profile.email != userData.email) {
+        await this.fxai._handleEmailUpdated(profile.email);
+      }
+      log.debug("notifying profile changed for user ${uid}", userData);
+      this._notifyProfileChange(userData.uid);
+      return profile;
+    });
+  },
+
+  async _getProfileCache() {
+    let data = await this.fxai.currentAccountState.getUserAccountData([
+      "profileCache",
+    ]);
+    return data ? data.profileCache : null;
+  },
+
+  async _fetchAndCacheProfileInternal() {
+    try {
+      const profileCache = await this._getProfileCache();
+      const etag = profileCache ? profileCache.etag : null;
+      let response;
+      try {
+        response = await this.client.fetchProfile(etag);
+      } catch (err) {
+        await this.fxai._handleTokenError(err);
+        // _handleTokenError always re-throws.
+        throw new Error("not reached!");
+      }
+
+      // response may be null if the profile was not modified (same ETag).
+      if (!response) {
+        return null;
+      }
+      return await this._cacheProfile(response);
+    } finally {
+      this._cachedAt = Date.now();
+      this._currentFetchPromise = null;
+    }
+  },
+
+  _fetchAndCacheProfile() {
+    if (!this._currentFetchPromise) {
+      this._currentFetchPromise = this._fetchAndCacheProfileInternal();
+    }
+    return this._currentFetchPromise;
+  },
+
+  // Returns cached data right away if available, otherwise returns null - if
+  // it returns null, or if the profile is possibly stale, it attempts to
+  // fetch the latest profile data in the background. After data is fetched a
+  // notification will be sent out if the profile has changed.
+  async getProfile() {
+    const profileCache = await this._getProfileCache();
+    if (!profileCache) {
+      // fetch and cache it in the background.
+      this._fetchAndCacheProfile().catch(err => {
+        log.error("Background refresh of initial profile failed", err);
+      });
+      return null;
+    }
+    if (Date.now() > this._cachedAt + this.PROFILE_FRESHNESS_THRESHOLD) {
+      // Note that _fetchAndCacheProfile isn't returned, so continues
+      // in the background.
+      this._fetchAndCacheProfile().catch(err => {
+        log.error("Background refresh of profile failed", err);
+      });
+    } else {
+      log.trace("not checking freshness of profile as it remains recent");
+    }
+    return profileCache.profile;
+  },
+
+  // Get the user's profile data, fetching from the network if necessary.
+  // Most callers should instead use `getProfile()`; this methods exists to support
+  // callers who need to await the underlying network request.
+  async ensureProfile({ staleOk = false, forceFresh = false } = {}) {
+    if (staleOk && forceFresh) {
+      throw new Error("contradictory options specified");
+    }
+    const profileCache = await this._getProfileCache();
+    if (
+      forceFresh ||
+      !profileCache ||
+      (Date.now() > this._cachedAt + this.PROFILE_FRESHNESS_THRESHOLD &&
+        !staleOk)
+    ) {
+      const profile = await this._fetchAndCacheProfile().catch(err => {
+        log.error("Background refresh of profile failed", err);
+      });
+      if (profile) {
+        return profile;
+      }
+    }
+    log.trace("not checking freshness of profile as it remains recent");
+    return profileCache ? profileCache.profile : null;
+  },
+
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIObserver",
+    "nsISupportsWeakReference",
+  ]),
+};