Implementation of beginning of Declarative Web Request API backend

chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h

+// Copyright (c) 2012 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 CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_ACTION_H_
+#define CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_ACTION_H_
+#pragma once
+
+#include <string>
+#include <vector>
+
+#include "base/compiler_specific.h"
+#include "base/memory/linked_ptr.h"
+#include "tools/json_schema_compiler/any.h"
+
+namespace base {
+class Value;
+}
+
+namespace extensions {
+
+// Base class for all WebRequestActions of the declarative Web Request API.
+//
+// TODO(battre): Add method that corresponds to executing the action.
+class WebRequestAction {
+ public:
+  // Type identifiers for concrete WebRequestActions.
+  enum Type {
+    ACTION_CANCEL_REQUEST
+  };
+
+  WebRequestAction();
+  virtual ~WebRequestAction();
+
+  // Returns a bit vector representing extensions::RequestStages. The bit vector
+  // contains a 1 for each request stage during which the condition can be
+  // tested.
+  virtual int GetStages() const = 0;
+
+  virtual Type GetType() const = 0;
+
+  // Factory method that instantiates a concrete WebRequestAction
+  // implementation according to |json_action|, the representation of the
+  // WebRequestAction as received from the extension API.
+  // Sets |error| and returns NULL in case of an error.
+  static scoped_ptr<WebRequestAction> Create(const base::Value& json_action,
+                                             std::string* error);
+};
+
+// Immutable container for multiple actions.
+//
+// TODO(battre): As WebRequestActionSet can become the single owner of all
+// actions, we can optimize here by making some of them singletons (e.g. Cancel
+// actions).
+//
+// TODO(battre): Add method that corresponds to executing the action.
+class WebRequestActionSet {
+ public:
+  typedef std::vector<linked_ptr<json_schema_compiler::any::Any> > AnyVector;
+  typedef std::vector<linked_ptr<WebRequestAction> > Actions;
+
+  explicit WebRequestActionSet(const Actions& actions);
+  virtual ~WebRequestActionSet();
+
+  // Factory method that instantiates a WebRequestActionSet according to
+  // |actions| which represents the array of actions received from the
+  // extension API.
+  static scoped_ptr<WebRequestActionSet> Create(const AnyVector& actions,
+                                                std::string* error);
+
+  const Actions& actions() const { return actions_; }
+
+ private:
+  Actions actions_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebRequestActionSet);
+};
+
+//
+// The following are concrete actions.
+//
+
+// Action that instructs to cancel a network request.
+class WebRequestCancelAction : public WebRequestAction {
+ public:
+  WebRequestCancelAction();
+  virtual ~WebRequestCancelAction();
+
+  // Implementation of WebRequestAction:
+  virtual int GetStages() const OVERRIDE;
+  virtual Type GetType() const OVERRIDE;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(WebRequestCancelAction);
+};
+
+// TODO(battre) Implement further actions:
+// Redirect to constant url, Redirect by RegEx, Set header, Remove header, ...
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_ACTION_H_