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

chrome/browser/search/local_files_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_files_ntp_source.h"
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/location.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "base/strings/string_util.h"
 #include "base/threading/thread_restrictions.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/url_data_source.h"
+#include "third_party/re2/re2/re2.h"
+#include "third_party/re2/re2/stringpiece.h"
 
 namespace {
 
 const char kBasePath[] = "chrome/browser/resources/local_ntp";
 
+// Matches lines of form '<include src="foo">' and captures 'foo'.
+const std::string kInlineResouceRegex = "<include.*?src\\=[\"'](.+?)[\"'].*?>";

[Mathieu, 2015/10/29 20:15:19]

nit: Resource

+
 void CallbackWithLoadedResource(
     const std::string& origin,
     const content::URLDataSource::GotDataCallback& callback,
     const std::string& content) {
   std::string output = content;
   if (!origin.empty())
     base::ReplaceFirstSubstringAfterOffset(&output, 0, "{{ORIGIN}}", origin);
 
   scoped_refptr<base::RefCountedString> response(
       base::RefCountedString::TakeString(&output));
   callback.Run(response.get());
 }
 
 // Read a file to a string and return.
 std::string ReadFileAndReturn(const base::FilePath& path) {
   std::string data;
   // This call can fail, but it doesn't matter for our purposes. If it fails,
   // we simply return an empty string.
   base::ReadFileToString(path, &data);
   return data;
 }
 
 }  // namespace
 
 namespace local_ntp {
 
+void FlattenLocalInclude(
+    const content::URLDataSource::GotDataCallback& callback,
+    std::string topLevelResource,
+    base::RefCountedMemory* inlineResource);
+
+// Helper method invoked by both CheckLocalIncludes and FlattenLocalInclude.
+// Checks for any <include> directives; if any are found, loads the associated
+// file and calls FlattenLocalInclude with the result. Otherwise, processing
+// is done, and so the original callback is invoked.
+void CheckLocalIncludesHelper(
+    const content::URLDataSource::GotDataCallback& callback,
+    std::string resource) {

[Mathieu, 2015/10/29 20:15:19]

const 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);
+    SendLocalFileResource(filename, wrapper);
+  } else {
+    callback.Run(base::RefCountedString::TakeString(&resource));
+  }
+}
+
+// Wrapper around the above helper function for use as a callback. Processes
+// local files to inline any files indicated by an <include> directive.
+void CheckLocalIncludes(
+    const content::URLDataSource::GotDataCallback& callback,
+    base::RefCountedMemory* resource) {
+  std::string resourceAsStr(resource->front_as<char>(), resource->size());
+  CheckLocalIncludesHelper(callback, resourceAsStr);
+}
+
+// Replaces the first <include> directive found with the given file contents.
+// Afterwards, re-invokes CheckLocalIncludesHelper to handle any subsequent
+// <include>s, including those which may have been added by the newly-inlined
+// resource.
+void FlattenLocalInclude(
+    const content::URLDataSource::GotDataCallback& callback,
+    std::string topLevelResource,

[Mathieu, 2015/10/29 20:15:19]

const std::string& ?

+    base::RefCountedMemory* inlineResource) {
+  std::string inlineAsStr(inlineResource->front_as<char>(),
+                          inlineResource->size());
+  re2::RE2::Replace(&topLevelResource, kInlineResouceRegex, inlineAsStr);
+  CheckLocalIncludesHelper(callback, topLevelResource);
+}
+
 void SendLocalFileResource(
     const std::string& path,
     const content::URLDataSource::GotDataCallback& callback) {
   SendLocalFileResourceWithOrigin(path, std::string(), callback);
 }
 
 void SendLocalFileResourceWithOrigin(
     const std::string& path,
     const std::string& origin,
     const content::URLDataSource::GotDataCallback& callback) {
   base::FilePath fullpath;
   PathService::Get(base::DIR_SOURCE_ROOT, &fullpath);
   fullpath = fullpath.AppendASCII(kBasePath).AppendASCII(path);
+  content::URLDataSource::GotDataCallback wrapper =
+      base::Bind(&CheckLocalIncludes, callback);
   base::PostTaskAndReplyWithResult(
       content::BrowserThread::GetBlockingPool(), FROM_HERE,
       base::Bind(&ReadFileAndReturn, fullpath),
-      base::Bind(&CallbackWithLoadedResource, origin, callback));
+      base::Bind(&CallbackWithLoadedResource, origin, wrapper));
 }
 
 }  // namespace local_ntp