Componentize component_updater: Move over a bunch of files to the component.

BUG=371463

Review URL: https://codereview.chromium.org/449643002

Cr-Commit-Position: refs/heads/master@{#290499}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@290499 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 230 insertions, 0 deletions

diff --git a/components/component_updater/component_updater_service.h b/components/component_updater/component_updater_service.h
new file mode 100644
index 0000000..9ea5d30
--- /dev/null
+++ b/components/component_updater/component_updater_service.h
@@ -0,0 +1,230 @@
+// Copyright 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.
+
+#ifndef COMPONENTS_COMPONENT_UPDATER_COMPONENT_UPDATER_SERVICE_H_
+#define COMPONENTS_COMPONENT_UPDATER_COMPONENT_UPDATER_SERVICE_H_
+
+#include <string>
+#include <vector>
+
+#include "base/callback_forward.h"
+#include "base/gtest_prod_util.h"
+#include "base/memory/ref_counted.h"
+#include "base/version.h"
+#include "url/gurl.h"
+
+class ComponentsUI;
+
+namespace base {
+class DictionaryValue;
+class FilePath;
+class SequencedTaskRunner;
+}
+
+namespace net {
+class URLRequestContextGetter;
+class URLRequest;
+}
+
+namespace content {
+class ResourceThrottle;
+}
+
+namespace component_updater {
+
+class Configurator;
+class OnDemandUpdater;
+
+// Component specific installers must derive from this class and implement
+// OnUpdateError() and Install(). A valid instance of this class must be
+// given to ComponentUpdateService::RegisterComponent().
+class ComponentInstaller {
+ public:
+  // Called by the component updater on the main thread when there was a
+  // problem unpacking or verifying the component. |error| is a non-zero
+  // value which is only meaningful to the component updater.
+  virtual void OnUpdateError(int error) = 0;
+
+  // Called by the component updater when a component has been unpacked
+  // and is ready to be installed. |manifest| contains the CRX manifest
+  // json dictionary and |unpack_path| contains the temporary directory
+  // with all the unpacked CRX files. This method may be called from
+  // a thread other than the main thread.
+  virtual bool Install(const base::DictionaryValue& manifest,
+                       const base::FilePath& unpack_path) = 0;
+
+  // Set |installed_file| to the full path to the installed |file|. |file| is
+  // the filename of the file in this component's CRX. Returns false if this is
+  // not possible (the file has been removed or modified, or its current
+  // location is unknown). Otherwise, returns true.
+  virtual bool GetInstalledFile(const std::string& file,
+                                base::FilePath* installed_file) = 0;
+
+  virtual ~ComponentInstaller() {}
+};
+
+// Describes a particular component that can be installed or updated. This
+// structure is required to register a component with the component updater.
+// |pk_hash| is the SHA256 hash of the component's public key. If the component
+// is to be installed then version should be "0" or "0.0", else it should be
+// the current version. |fingerprint|, and |name| are optional.
+// |allow_background_download| specifies that the component can be background
+// downloaded in some cases. The default for this value is |true| and the value
+// can be overriden at the registration time. This is a temporary change until
+// the issue 340448 is resolved.
+struct CrxComponent {
+  std::vector<uint8> pk_hash;
+  ComponentInstaller* installer;
+  Version version;
+  std::string fingerprint;
+  std::string name;
+  bool allow_background_download;
+  CrxComponent();
+  ~CrxComponent();
+};
+
+struct CrxUpdateItem;
+
+// The component update service is in charge of installing or upgrading
+// select parts of chrome. Each part is called a component and managed by
+// instances of CrxComponent registered using RegisterComponent(). On the
+// server, each component is packaged as a CRX which is the same format used
+// to package extensions. To the update service each component is identified
+// by its public key hash (CrxComponent::pk_hash). If there is an update
+// available and its version is bigger than (CrxComponent::version), it will
+// be downloaded, verified and unpacked. Then component-specific installer
+// ComponentInstaller::Install (of CrxComponent::installer) will be called.
+//
+// During the normal operation of the component updater some specific
+// notifications are fired, like COMPONENT_UPDATER_STARTED and
+// COMPONENT_UPDATE_FOUND. See notification_type.h for more details.
+//
+// All methods are safe to call ONLY from the browser's main thread.
+class ComponentUpdateService {
+ public:
+  enum Status { kOk, kReplaced, kInProgress, kError };
+
+  // Defines an interface to observe ComponentUpdateService. It provides
+  // notifications when state changes occur for the service or for the
+  // registered components.
+  class Observer {
+   public:
+    enum Events {
+      // Sent when the component updater starts doing update checks.
+      COMPONENT_UPDATER_STARTED,
+
+      // Sent when the component updater is going to take a long nap.
+      COMPONENT_UPDATER_SLEEPING,
+
+      // Sent when there is a new version of a registered component. After
+      // the notification is sent the component will be downloaded.
+      COMPONENT_UPDATE_FOUND,
+
+      // Sent when the new component has been downloaded and an installation
+      // or upgrade is about to be attempted.
+      COMPONENT_UPDATE_READY,
+
+      // Sent when a component has been successfully updated.
+      COMPONENT_UPDATED,
+
+      // Sent when a component has not been updated following an update check:
+      // either there was no update available, or an update failed.
+      COMPONENT_NOT_UPDATED,
+
+      // Sent when component bytes are being downloaded.
+      COMPONENT_UPDATE_DOWNLOADING,
+    };
+
+    virtual ~Observer() {}
+
+    // The component updater service will call this function when an interesting
+    // state change happens. If the |id| is specified, then the event is fired
+    // on behalf of a specific component. The implementors of this interface are
+    // expected to filter the relevant events based on the component id.
+    virtual void OnEvent(Events event, const std::string& id) = 0;
+  };
+
+  // Adds an observer for this class. An observer should not be added more
+  // than once. The caller retains the ownership of the observer object.
+  virtual void AddObserver(Observer* observer) = 0;
+
+  // Removes an observer. It is safe for an observer to be removed while
+  // the observers are being notified.
+  virtual void RemoveObserver(Observer* observer) = 0;
+
+  // Start doing update checks and installing new versions of registered
+  // components after Configurator::InitialDelay() seconds.
+  virtual Status Start() = 0;
+
+  // Stop doing update checks. In-flight requests and pending installations
+  // will not be canceled.
+  virtual Status Stop() = 0;
+
+  // Add component to be checked for updates. You can call this method
+  // before calling Start().
+  virtual Status RegisterComponent(const CrxComponent& component) = 0;
+
+  // Returns a list of registered components.
+  virtual std::vector<std::string> GetComponentIDs() const = 0;
+
+  // Returns an interface for on-demand updates. On-demand updates are
+  // proactively triggered outside the normal component update service schedule.
+  virtual OnDemandUpdater& GetOnDemandUpdater() = 0;
+
+  // This method is used to trigger an on-demand update for component |crx_id|.
+  // This can be used when loading a resource that depends on this component.
+  //
+  // |callback| is called on the main thread once the on-demand update is
+  // complete, regardless of success. |callback| may be called immediately
+  // within the method body.
+  //
+  // Additionally, this function implements an embedder-defined cooldown
+  // interval between on demand update attempts. This behavior is intended
+  // to be defensive against programming bugs, usually triggered by web fetches,
+  // where the on-demand functionality is invoked too often. If this function
+  // is called while still on cooldown, |callback| will be called immediately.
+  virtual void MaybeThrottle(const std::string& crx_id,
+                             const base::Closure& callback) = 0;
+
+  // Returns a task runner suitable for use by component installers.
+  virtual scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner() = 0;
+
+  virtual ~ComponentUpdateService() {}
+
+ private:
+  // Returns details about registered component in the |item| parameter. The
+  // function returns true in case of success and false in case of errors.
+  virtual bool GetComponentDetails(const std::string& component_id,
+                                   CrxUpdateItem* item) const = 0;
+
+  friend class ::ComponentsUI;
+};
+
+typedef ComponentUpdateService::Observer ServiceObserver;
+
+class OnDemandUpdater {
+ public:
+  virtual ~OnDemandUpdater() {}
+
+ private:
+  friend class OnDemandTester;
+  friend class ::ComponentsUI;
+
+  // Triggers an update check for a component. |component_id| is a value
+  // returned by GetCrxComponentID(). If an update for this component is already
+  // in progress, the function returns |kInProgress|. If an update is available,
+  // the update will be applied. The caller can subscribe to component update
+  // service notifications to get an indication about the outcome of the
+  // on-demand update. The function does not implement any cooldown interval.
+  virtual ComponentUpdateService::Status OnDemandUpdate(
+      const std::string& component_id) = 0;
+};
+
+// Creates the component updater. You must pass a valid |config| allocated on
+// the heap which the component updater will own.
+ComponentUpdateService* ComponentUpdateServiceFactory(Configurator* config);
+
+}  // namespace component_updater
+
+#endif  // COMPONENTS_COMPONENT_UPDATER_COMPONENT_UPDATER_SERVICE_H_