Implement <webview>.addContentScript/removeContentScript API [2]

extensions/browser/user_script_loader.h

 // 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 EXTENSIONS_BROWSER_USER_SCRIPT_LOADER_H_
 #define EXTENSIONS_BROWSER_USER_SCRIPT_LOADER_H_
 
 #include <map>
 #include <set>
 
@@ skipping 26 matching lines @@
 // script reloading completes. Script loading lives on the UI thread. Instances
 // of this class are embedded within classes with names ending in
 // UserScriptMaster. These "master" classes implement the strategy for which
 // scripts to load/unload on this logical unit of scripts.
 class UserScriptLoader : public content::NotificationObserver {
  public:
   using PathAndDefaultLocale = std::pair<base::FilePath, std::string>;
   using HostsInfo = std::map<HostID, PathAndDefaultLocale>;
 
   using SubstitutionMap = std::map<std::string, std::string>;
-  using LoadUserScriptsContentFunction =
-      base::Callback<bool(const HostID&,
-                          UserScript::File*,
-                          const SubstitutionMap*,
-                          const scoped_refptr<ContentVerifier>&)>;
 
   // Parses the includes out of |script| and returns them in |includes|.
   static bool ParseMetadataHeader(const base::StringPiece& script_text,
                                   UserScript* script);
 
   UserScriptLoader(content::BrowserContext* browser_context,
-                   const HostID& host_id,
-                   const scoped_refptr<ContentVerifier>& content_verifier);
+                   const HostID& host_id);
   ~UserScriptLoader() override;
 
-  // A wrapper around the method to load user scripts, which is normally run on
-  // the file thread. Exposed only for tests.
-  void LoadScriptsForTest(UserScriptList* user_scripts);
-
   // Add |scripts| to the set of scripts managed by this loader.
   void AddScripts(const std::set<UserScript>& scripts);
 
+  // Add |scripts| to the set of scripts managed by this loader.
+  // The fetch of the content of the script starts URL request
+  // to the associated render specified by
+  // |render_process_id, render_view_id|.
+  void AddScripts(const std::set<UserScript>& scripts,
+                  int render_process_id,
+                  int render_view_id);
+
   // Remove |scripts| from the set of scripts managed by this loader.
   void RemoveScripts(const std::set<UserScript>& scripts);
 
   // Clears the set of scripts managed by this loader.
-  void ClearScripts();
+  // If |is_clear| is true, will attempt to load scripts.
+  void ClearScripts(bool is_clear);
 
   // Initiates procedure to start loading scripts on the file thread.
   void StartLoad();
 
   // Returns true if we have any scripts ready.
   bool scripts_ready() const { return shared_memory_.get() != NULL; }
 
+  // Pickle user scripts and return pointer to the shared memory.
+  static scoped_ptr<base::SharedMemory> Serialize(
+      const extensions::UserScriptList& scripts);
+
  protected:
-  // Updates |hosts_info_| to contain info for each element of
-  // |changed_hosts_|.
-  virtual void UpdateHostsInfo(const std::set<HostID>& changed_hosts) = 0;
+  struct UserScriptRenderInfo {

[Devlin, 2015/04/16 20:19:28]

(Almost all of) this is a layering violation. The UserScriptLoader base class
shouldn't have any knowledge of webui, and shouldn't need to store the script
info like this.

[Xi Han, 2015/04/17 21:44:20]

You are right. Refactoring is done to move all these webui-related routing info
to WebUIuserScriptLoader.

+    int render_process_id;
+    int render_view_id;
 
-  // Returns a function pointer of a static funcion to load user scripts.
-  // Derived classes can specify their ways to load scripts in the static
-  // function they return.
-  // Note: It has to be safe to call multiple times.
-  virtual LoadUserScriptsContentFunction GetLoadUserScriptsFunction() = 0;
+    UserScriptRenderInfo() {
+      render_process_id = -1;
+      render_view_id = -1;
+    }
 
-  // Adds the |host_id, location| to the |hosts_info_| map.
-  // Only inserts the entry to the map when the given host_id doesn't
-  // exists.
-  void AddHostInfo(const HostID& host_id, const PathAndDefaultLocale& location);
+    UserScriptRenderInfo(int render_process_id, int render_view_id) {
+      this->render_process_id = render_process_id;
+      this->render_view_id = render_view_id;
+    }
 
-  // Removes the entries with the given host_id from the |hosts_info_| map.
-  void RemoveHostInfo(const HostID& host_id);
+    bool operator<(const UserScriptRenderInfo& other) {
+      if (render_process_id != other.render_process_id)
+        return render_process_id < other.render_process_id;
+
+      if (render_view_id != other.render_view_id)
+        return render_view_id < other.render_view_id;
+
+      return false;
+    }
+  };
+
+  using UserScriptRenderInfoMap = std::map<int, UserScriptRenderInfo>;
+
+  // Allows the derived classes have different ways to load user scripts.
+  virtual void LoadScripts(const std::set<HostID>& changed_hosts,
+                           const std::set<int>& added_script_ids) = 0;
+
+  bool GetScriptRenderInfo(int script_id, UserScriptRenderInfo* info);
+  void RemoveScriptRenderInfo(int script_id);
 
   // Sets the flag if the initial set of hosts has finished loading; if it's
   // set to be true, calls AttempLoad() to bootstrap.
   void SetReady(bool ready);
 
+  // Called once we have finished loading the scripts on the file thread.
+  void OnScriptsLoaded(scoped_ptr<UserScriptList> user_scripts,
+                       scoped_ptr<base::SharedMemory> shared_memory);
+
   content::BrowserContext* browser_context() const { return browser_context_; }
   const HostID& host_id() const { return host_id_; }
 
+  // List of scripts from currently-installed extensions we should load.
+  scoped_ptr<UserScriptList> user_scripts_;
+
  private:
   // content::NotificationObserver implementation.
   void Observe(int type,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override;
 
   // Returns whether or not it is possible that calls to AddScripts(),
   // RemoveScripts(), and/or ClearScripts() have caused any real change in the
   // set of scripts to be loaded.
   bool ScriptsMayHaveChanged() const;
 
   // Attempts to initiate a load.
   void AttemptLoad();
 
-  // Called once we have finished loading the scripts on the file thread.
-  void OnScriptsLoaded(scoped_ptr<UserScriptList> user_scripts,
-                       scoped_ptr<base::SharedMemory> shared_memory);
-
   // Sends the renderer process a new set of user scripts. If
   // |changed_hosts| is not empty, this signals that only the scripts from
   // those hosts should be updated. Otherwise, all hosts will be
   // updated.
   void SendUpdate(content::RenderProcessHost* process,
                   base::SharedMemory* shared_memory,
                   const std::set<HostID>& changed_hosts);
 
   bool is_loading() const {
     // Ownership of |user_scripts_| is passed to the file thread when loading.
     return user_scripts_.get() == NULL;
   }
 
   // Manages our notification registrations.
   content::NotificationRegistrar registrar_;
 
   // Contains the scripts that were found the last time scripts were updated.
   scoped_ptr<base::SharedMemory> shared_memory_;
 
-  // List of scripts from currently-installed extensions we should load.
-  scoped_ptr<UserScriptList> user_scripts_;
-
-  // Maps host info needed for localization to a host ID.
-  HostsInfo hosts_info_;
-
   // The mutually-exclusive sets of scripts that were added or removed since the
   // last script load.
   std::set<UserScript> added_scripts_;
   std::set<UserScript> removed_scripts_;
 
   // Indicates whether the the collection of scripts should be cleared before
   // additions and removals on the next script load.
   bool clear_scripts_;
 
   // The IDs of the extensions which changed in the last update sent to the
@@ skipping 11 matching lines @@
   // Whether or not we are currently loading.
   bool is_loading_;
 
   // The browser_context for which the scripts managed here are installed.
   content::BrowserContext* browser_context_;
 
   // ID of the host that owns these scripts, if any. This is only set to a
   // non-empty value for declarative user script shared memory regions.
   HostID host_id_;
 
-  // Manages content verification of the loaded user scripts.
-  scoped_refptr<ContentVerifier> content_verifier_;
+  // Caches the render info of script from WebUI when AddScripts is called.
+  // When starting to load the script, we look up this map to retrieve the
+  // render info. It is used for the script from WebUI only, since the fetch
+  // of script content requires the info of associated render.
+  UserScriptRenderInfoMap script_render_info_map_;
 
   base::WeakPtrFactory<UserScriptLoader> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(UserScriptLoader);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_USER_SCRIPT_LOADER_H_