Prepare declarativeContent API for new script injection feature. Added Javascript types and functio…

chrome/browser/extensions/api/declarative_content/content_action.cc

 // 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.
 
 #include "chrome/browser/extensions/api/declarative_content/content_action.h"
 
 #include <map>
 
 #include "base/lazy_instance.h"
 #include "base/strings/stringprintf.h"
@@ skipping 11 matching lines @@
 namespace extensions {
 
 namespace keys = declarative_content_constants;
 
 namespace {
 // Error messages.
 const char kInvalidInstanceTypeError[] =
     "An action has an invalid instanceType: %s";
 const char kNoPageAction[] =
     "Can't use declarativeContent.ShowPageAction without a page action";
+const char kMissingParameter[] = "Missing parameter is required: %s";
 
 #define INPUT_FORMAT_VALIDATE(test) do { \
     if (!(test)) { \
       *bad_message = true; \
       return scoped_refptr<ContentAction>(NULL); \
     } \
   } while (0)
 
 //
 // The following are concrete actions.
@@ skipping 45 matching lines @@
             ->GetExtensionById(extension_id, ExtensionRegistry::EVERYTHING);
     if (!extension)
       return NULL;
     return ExtensionActionManager::Get(profile)->GetPageAction(*extension);
   }
   virtual ~ShowPageAction() {}
 
   DISALLOW_COPY_AND_ASSIGN(ShowPageAction);
 };
 
+// Action that injects a content script.
+class RequestContentScript : public ContentAction {
+ public:
+  RequestContentScript(const std::vector<std::string>& css_file_names,
+                       const std::vector<std::string>& js_file_names,
+                       bool all_frames,
+                       bool match_about_blank)
+      : css_file_names_(css_file_names),
+        js_file_names_(js_file_names),
+        all_frames_(all_frames),
+        match_about_blank_(match_about_blank) {}
+
+  static scoped_refptr<ContentAction> Create(const Extension* extension,
+                                             const base::DictionaryValue* dict,
+                                             std::string* error,
+                                             bool* bad_message);
+
+  // Implementation of ContentAction:
+  virtual Type GetType() const OVERRIDE {
+    return ACTION_REQUEST_CONTENT_SCRIPT;
+  }
+
+  virtual void Apply(const std::string& extension_id,
+                     const base::Time& extension_install_time,
+                     ApplyInfo* apply_info) const OVERRIDE {
+    // TODO(markdittmer): Invoke UserScriptMaster declarative script loader:
+    // load new user script.
+  }
+
+  virtual void Revert(const std::string& extension_id,
+                      const base::Time& extension_install_time,
+                      ApplyInfo* apply_info) const OVERRIDE {
+    // TODO(markdittmer): Invoke UserScriptMaster declarative script loader:
+    // do not load user script if Apply() runs again on the same page.
+  }
+
+ private:
+  virtual ~RequestContentScript() {}
+
+  std::vector<std::string> css_file_names_;
+  std::vector<std::string> js_file_names_;
+  bool all_frames_;
+  bool match_about_blank_;
+
+  DISALLOW_COPY_AND_ASSIGN(RequestContentScript);
+};
+
+// Helper for getting JS collections into C++.
+static bool AppendJSStringsToCPPStrings(const base::ListValue& append_strings,
+                                        std::vector<std::string>* append_to) {
+  for (base::ListValue::const_iterator it = append_strings.begin();
+       it != append_strings.end();
+       ++it) {
+    std::string value;
+    if ((*it)->GetAsString(&value)) {
+      append_to->push_back(value);
+    } else {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+// static
+scoped_refptr<ContentAction> RequestContentScript::Create(
+    const Extension* extension,
+    const base::DictionaryValue* dict,
+    std::string* error,
+    bool* bad_message) {
+  std::vector<std::string> css_file_names;
+  std::vector<std::string> js_file_names;
+  bool all_frames = false;
+  bool match_about_blank = false;
+  const base::ListValue* list_value;
+
+  if (!dict->HasKey(keys::kCss) && !dict->HasKey(keys::kJs)) {
+    *error = base::StringPrintf(kMissingParameter, "css or js");
+    return scoped_refptr<ContentAction>();
+  }
+  INPUT_FORMAT_VALIDATE(
+      !dict->HasKey(keys::kCss) ||

[Jeffrey Yasskin, 2014/07/17 20:39:14]

Use more if()s here. Chains of || and && that rely on short-circuiting tend to
be hard to understand. I believe:

if (dict->HasKey(keys::kCss)) {
  INPUT_FORMAT_VALIDATE(dict->GetList(keys::kCss, &list_value));
  INPUT_FORMAT_VALIDATE(AppendJSStringsToCPPStrings(*list_value,
&css_file_names));
}

will work fine in this case. It also makes it easier to set breakpoints in
precise places.

[Mark Dittmer, 2014/07/17 23:58:14]

Done.

+      (dict->GetList(keys::kCss, &list_value) &&
+       AppendJSStringsToCPPStrings(*list_value, &css_file_names)));
+  INPUT_FORMAT_VALIDATE(
+      !dict->HasKey(keys::kJs) ||
+      (dict->GetList(keys::kJs, &list_value) &&
+       AppendJSStringsToCPPStrings(*list_value, &js_file_names)));
+  INPUT_FORMAT_VALIDATE(!dict->HasKey(keys::kAllFrames) ||
+                        dict->GetBoolean(keys::kAllFrames, &all_frames));
+  INPUT_FORMAT_VALIDATE(
+      !dict->HasKey(keys::kMatchAboutBlank) ||
+      dict->GetBoolean(keys::kMatchAboutBlank, &match_about_blank));
+
+  return scoped_refptr<ContentAction>(new RequestContentScript(
+      css_file_names, js_file_names, all_frames, match_about_blank));
+}
+
 struct ContentActionFactory {
   // Factory methods for ContentAction instances. |extension| is the extension
   // for which the action is being created. |dict| contains the json dictionary
   // that describes the action. |error| is used to return error messages in case
   // the extension passed an action that was syntactically correct but
   // semantically incorrect. |bad_message| is set to true in case |dict| does
   // not confirm to the validated JSON specification.
   typedef scoped_refptr<ContentAction>(*FactoryMethod)(
       const Extension* /* extension */,
       const base::DictionaryValue* /* dict */,
       std::string* /* error */,
       bool* /* bad_message */);
   // Maps the name of a declarativeContent action type to the factory
   // function creating it.
   std::map<std::string, FactoryMethod> factory_methods;
 
   ContentActionFactory() {
     factory_methods[keys::kShowPageAction] =
         &ShowPageAction::Create;
+    factory_methods[keys::kRequestContentScript] =
+        &RequestContentScript::Create;
   }
 };
 
 base::LazyInstance<ContentActionFactory>::Leaky
     g_content_action_factory = LAZY_INSTANCE_INITIALIZER;
 
 }  // namespace
 
 //
 // ContentAction
@@ skipping 24 matching lines @@
       factory_method_iter = factory.factory_methods.find(instance_type);
   if (factory_method_iter != factory.factory_methods.end())
     return (*factory_method_iter->second)(
         extension, action_dict, error, bad_message);
 
   *error = base::StringPrintf(kInvalidInstanceTypeError, instance_type.c_str());
   return scoped_refptr<ContentAction>();
 }
 
 }  // namespace extensions