Precache policy-for-extensions for device-local accounts.

chrome/browser/chromeos/policy/device_local_account_extension_tracker.cc

+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/chromeos/policy/device_local_account_extension_tracker.h"
+
+#include "base/logging.h"
+#include "base/prefs/pref_value_map.h"
+#include "base/values.h"
+#include "chrome/browser/chromeos/policy/device_local_account.h"
+#include "chrome/browser/extensions/policy_handlers.h"
+#include "components/policy/core/common/policy_map.h"
+#include "components/policy/core/common/policy_namespace.h"
+#include "components/policy/core/common/schema.h"
+#include "components/policy/core/common/schema_registry.h"
+#include "extensions/browser/pref_names.h"
+
+namespace policy {
+
+DeviceLocalAccountExtensionTracker::DeviceLocalAccountExtensionTracker(
+    const DeviceLocalAccount& account,
+    CloudPolicyStore* store,
+    SchemaRegistry* schema_registry)
+    : store_(store),
+      schema_registry_(schema_registry) {
+  if (account.type == DeviceLocalAccount::TYPE_KIOSK_APP) {
+    // This is easy: Just add a component for the app id.
+    PolicyNamespace ns(POLICY_DOMAIN_EXTENSIONS, account.kiosk_app_id);
+    schema_registry_->RegisterComponent(ns, Schema());
+  } else if (account.type == DeviceLocalAccount::TYPE_PUBLIC_SESSION) {
+    // For public sessions, track the value of the ExtensionInstallForcelist
+    // policy.
+    store_->AddObserver(this);
+    UpdateFromStore();
+  } else {
+    NOTREACHED();
+  }
+
+  schema_registry_->SetReady(POLICY_DOMAIN_EXTENSIONS);
+}
+
+DeviceLocalAccountExtensionTracker::~DeviceLocalAccountExtensionTracker() {
+  store_->RemoveObserver(this);
+}
+
+void DeviceLocalAccountExtensionTracker::OnStoreLoaded(
+    CloudPolicyStore* store) {
+  UpdateFromStore();
+}
+
+void DeviceLocalAccountExtensionTracker::OnStoreError(CloudPolicyStore* store) {
+  UpdateFromStore();
+}
+
+void DeviceLocalAccountExtensionTracker::UpdateFromStore() {
+  const policy::PolicyMap& policy_map = store_->policy_map();
+
+  extensions::ExtensionInstallForcelistPolicyHandler policy_handler;
+  if (!policy_handler.CheckPolicySettings(policy_map, NULL))
+    return;
+
+  PrefValueMap pref_value_map;
+  policy_handler.ApplyPolicySettings(policy_map, &pref_value_map);
+
+  const base::Value* value = NULL;
+  const base::DictionaryValue* dict = NULL;
+  if (!pref_value_map.GetValue(extensions::pref_names::kInstallForceList,
+                               &value) ||
+      !value->GetAsDictionary(&dict)) {
+    return;
+  }
+
+  for (base::DictionaryValue::Iterator it(*dict); !it.IsAtEnd(); it.Advance()) {
+    PolicyNamespace ns(POLICY_DOMAIN_EXTENSIONS, it.key());
+    schema_registry_->RegisterComponent(ns, Schema());
+  }
+
+  // Removing an extension from a public session at runtime can happen but is
+  // a rare event. In that case we leave the extension ID in the SchemaRegistry,
+  // and it will be purged on the next restart.
+}
+
+}  // namespace policy