1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef EXTENSIONS_RENDERER_USER_SCRIPT_SCHEDULER_H_ 6 #define EXTENSIONS_RENDERER_USER_SCRIPT_SCHEDULER_H_ 7 8 #include <map> 9 #include <queue> 10 11 #include "base/memory/linked_ptr.h" 12 #include "base/memory/weak_ptr.h" 13 #include "extensions/common/user_script.h" 14 15 class RenderView; 16 struct ExtensionMsg_ExecuteCode_Params; 17 18 namespace blink { 19 class WebFrame; 20 } 21 22 namespace extensions { 23 class Dispatcher; 24 25 // Implements support for injecting scripts at different times in the document 26 // loading process. The different possible time are described in 27 // UserScript::RunLocation. 28 // 29 // Currently, determining idleness is simple: it is whichever of the following 30 // happens first: 31 // 32 // a) When the initial DOM for a page is complete + kUserScriptIdleTimeout, 33 // b) or when the page has completely loaded including all subresources. 34 // 35 // The intent of this mechanism is to prevent user scripts from slowing down 36 // fast pages (run after load), while still allowing them to run relatively 37 // timely for pages with lots of slow subresources. 38 // 39 // NOTE: this class does not inherit from RenderViewObserver on purpose. The 40 // reason is that this object is per frame, and a frame can move across 41 // RenderViews thanks to adoptNode. So we have each RenderView's 42 // ExtensionHelper proxy these calls to the renderer process' Dispatcher, 43 // which contains the mapping from WebFrame to us. 44 class UserScriptScheduler { 45 public: 46 UserScriptScheduler(blink::WebFrame* frame, Dispatcher* dispatcher); 47 ~UserScriptScheduler(); 48 49 void ExecuteCode(const ExtensionMsg_ExecuteCode_Params& params); 50 void DidCreateDocumentElement(); 51 void DidFinishDocumentLoad(); 52 void DidFinishLoad(); 53 void DidStartProvisionalLoad(); 54 55 private: 56 typedef 57 std::queue<linked_ptr<ExtensionMsg_ExecuteCode_Params> > 58 ExecutionQueue; 59 60 // Run user scripts, except if they've already run for this frame, or the 61 // frame has been destroyed. 62 void MaybeRun(); 63 64 // Backend for the IPC Message ExecuteCode in addition to being used 65 // internally. 66 void ExecuteCodeImpl(const ExtensionMsg_ExecuteCode_Params& params); 67 68 // Get all child frames of parent_frame, returned by frames_vector. 69 bool GetAllChildFrames(blink::WebFrame* parent_frame, 70 std::vector<blink::WebFrame*>* frames_vector) const; 71 72 // Call to signify thet the idle timeout has expired. 73 void IdleTimeout(); 74 75 base::WeakPtrFactory<UserScriptScheduler> weak_factory_; 76 77 // The Frame we will run scripts in. 78 blink::WebFrame* frame_; 79 80 // The current location in the document loading process. 81 // Will be UserScript::UNDEFINED if it is before any scripts should be run. 82 UserScript::RunLocation current_location_; 83 84 // Whether we have already run the idle scripts. 85 bool has_run_idle_; 86 87 // This is only used if we're for the main frame. 88 std::map<UserScript::RunLocation, ExecutionQueue> pending_execution_map_; 89 90 Dispatcher* dispatcher_; 91 }; 92 93 } // namespace extensions 94 95 #endif // EXTENSIONS_RENDERER_USER_SCRIPT_SCHEDULER_H_ 96