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

chrome/browser/search/local_ntp_source.cc

Index: chrome/browser/search/local_ntp_source.cc
diff --git a/chrome/browser/search/local_ntp_source.cc b/chrome/browser/search/local_ntp_source.cc
index 7fecfbfbe1274de97ae4bccf153a81c60e229ef4..888d4a6b4994d118fb487f5d84d19297da180dc0 100644
--- a/chrome/browser/search/local_ntp_source.cc
+++ b/chrome/browser/search/local_ntp_source.cc
@@ -26,6 +26,8 @@
 #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"
@@ -41,6 +43,8 @@ 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;
@@ -174,6 +178,44 @@ 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,
@@ -192,7 +234,9 @@ void LocalNtpSource::StartDataRequest(
     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;
     }
   }