Enabling included files when reloading local NTP with --local-ntp-reload.

chrome/browser/search/local_ntp_source.cc

 // Copyright 2013 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/search/local_ntp_source.h"
 
 #include "base/command_line.h"
 #include "base/json/json_string_value_serializer.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/field_trial.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/search/instant_io_context.h"
 #include "chrome/browser/search/local_files_ntp_source.h"
 #include "chrome/browser/search/search.h"
 #include "chrome/browser/search_engines/template_url_service_factory.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/search_engines/template_url_prepopulate_data.h"
 #include "components/search_engines/template_url_service.h"
 #include "grit/browser_resources.h"
 #include "grit/theme_resources.h"
 #include "net/url_request/url_request.h"
+#include "third_party/re2/re2/re2.h"
+#include "third_party/re2/re2/stringpiece.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/ui_base_switches.h"
 #include "ui/base/webui/jstemplate_builder.h"
 #include "ui/base/webui/web_ui_util.h"
 #include "ui/resources/grit/ui_resources.h"
 #include "url/gurl.h"
 
 namespace {
 
 // Signifies a locally constructed resource, i.e. not from grit/.
 const int kLocalResource = -1;
 
 const char kConfigDataFilename[] = "config.js";
 
+const std::string kInlineResouceRegex = "<include.*?src\\=[\"'](.+?)[\"'].*?>";

[fserb, 2015/10/06 15:53:17]

add a comment saying what you want to match with this.

+
 const struct Resource{
   const char* filename;
   int identifier;
   const char* mime_type;
 } kResources[] = {
   { "local-ntp.html", IDR_LOCAL_NTP_HTML, "text/html" },
   { "local-ntp.js", IDR_LOCAL_NTP_JS, "application/javascript" },
   { kConfigDataFilename, kLocalResource, "application/javascript" },
   { "local-ntp.css", IDR_LOCAL_NTP_CSS, "text/css" },
   { "images/close_2.png", IDR_CLOSE_2, "image/png" },
@@ skipping 113 matching lines @@
 LocalNtpSource::LocalNtpSource(Profile* profile) : profile_(profile) {
 }
 
 LocalNtpSource::~LocalNtpSource() {
 }
 
 std::string LocalNtpSource::GetSource() const {
   return chrome::kChromeSearchLocalNtpHost;
 }
 
+void FlattenLocalInclude(

[fserb, 2015/10/06 15:53:17]

can you add a comment here explaining the flow of callbacks and what we are
trying to achieve?

[Mathieu, 2015/10/09 15:10:38]

should be a private method and you wouldn't need to have a declaration and
definition

+    const content::URLDataSource::GotDataCallback& callback,
+    std::string topLevelResource,
+    base::RefCountedMemory* inlineResource);
+
+void CheckLocalIncludesHelper(
+    const content::URLDataSource::GotDataCallback& callback,
+    std::string resource) {
+  std::string filename;
+  re2::StringPiece resourceWrapper(resource);
+  if (re2::RE2::FindAndConsume(&resourceWrapper, kInlineResouceRegex,
+                               &filename)) {
+    content::URLDataSource::GotDataCallback wrapper =
+        base::Bind(&FlattenLocalInclude, callback, resource);
+    local_ntp::SendLocalFileResource(filename, wrapper);
+    //    FlattenLocalInclude(callback, resource,

[fserb, 2015/10/06 15:53:17]

remove those lines?

+    //    base::RefCountedString::TakeString(new std::string("foobar")));
+  } else {
+    callback.Run(base::RefCountedString::TakeString(&resource));
+  }
+}
+
+void CheckLocalIncludes(const content::URLDataSource::GotDataCallback& callback,

[fserb, 2015/10/06 15:53:17]

couldn't this and FlattenLocalInclude be the same function? And maybe passing
NULL to inlineResource?

[tmartino, 2015/10/15 20:54:16]

This doesn't really work, actually. We have two places where we need a function
to be used as a callback:

1. Inside CheckLocalIncludesHelper, where we create "wrapper", which binds to
the 3-arg function and provides a callback and a copy of the top-level resource.
When the callback is invoked, a copy of the *inline* resource is passed as the
last argument (per the spec for SendLocalFileResource).
2. Inside StartDataRequest, where we create "wrapper" which binds to the 2-arg
function and provides only a callback. When the callback is invoked, a copy of
the *top-level* resource is passed as the last argument (again, per the spec for
SendLocalFileResource).

Because SendLocalFileResource can only populate the last argument, and because
we use it to load both the top-level and the inline resource, I don't really see
a way we can condense these into the same function using a nullptr.

+                        base::RefCountedMemory* resource) {
+  std::string resourceAsStr(resource->front_as<char>(), resource->size());
+  CheckLocalIncludesHelper(callback, resourceAsStr);
+}
+
+void FlattenLocalInclude(
+    const content::URLDataSource::GotDataCallback& callback,
+    std::string topLevelResource,
+    base::RefCountedMemory* inlineResource) {
+  std::string inlineAsStr(inlineResource->front_as<char>(),
+                          inlineResource->size());
+  re2::RE2::Replace(&topLevelResource, kInlineResouceRegex, inlineAsStr);
+  CheckLocalIncludesHelper(callback, topLevelResource);
+}
+
 void LocalNtpSource::StartDataRequest(
     const std::string& path,
     int render_process_id,
     int render_frame_id,
     const content::URLDataSource::GotDataCallback& callback) {
   std::string stripped_path = StripParameters(path);
   if (stripped_path == kConfigDataFilename) {
     std::string config_data_js = GetConfigData(profile_);
     callback.Run(base::RefCountedString::TakeString(&config_data_js));
     return;
   }
 
 #if !defined(OFFICIAL_BUILD)
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(switches::kLocalNtpReload)) {
     if (stripped_path == "local-ntp.html" || stripped_path == "local-ntp.js" ||
         stripped_path == "local-ntp.css") {
       base::ReplaceChars(stripped_path, "-", "_", &stripped_path);
-      local_ntp::SendLocalFileResource(stripped_path, callback);
+      content::URLDataSource::GotDataCallback wrapper =
+          base::Bind(&CheckLocalIncludes, callback);
+      local_ntp::SendLocalFileResource(stripped_path, wrapper);
       return;
     }
   }
 #endif
 
   float scale = 1.0f;
   std::string filename;
   webui::ParsePathAndScale(
       GURL(GetLocalNtpPath() + stripped_path), &filename, &scale);
   ui::ScaleFactor scale_factor = ui::GetSupportedScaleFactor(scale);
@@ skipping 35 matching lines @@
     }
   }
   return false;
 }
 
 std::string LocalNtpSource::GetContentSecurityPolicyFrameSrc() const {
   // Allow embedding of most visited iframes.
   return base::StringPrintf("frame-src %s;",
                             chrome::kChromeSearchMostVisitedUrl);
 }