Support loading html file URLs in Mojo.

mojo/shell/local_fetcher.cc

 // Copyright 2015 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 "mojo/shell/local_fetcher.h"
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/format_macros.h"
 #include "base/message_loop/message_loop.h"
+#include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/trace_event.h"
 #include "mojo/common/common_type_converters.h"
 #include "mojo/common/data_pipe_utils.h"
 #include "mojo/common/url_type_converters.h"
 #include "mojo/util/filename_util.h"
 #include "url/url_util.h"
 
 namespace mojo {
 namespace shell {
@@ skipping 35 matching lines @@
   DataPipe data_pipe;
   response->body = data_pipe.consumer_handle.Pass();
   int64 file_size;
   if (base::GetFileSize(path_, &file_size)) {
     response->headers = Array<HttpHeaderPtr>(1);
     HttpHeaderPtr header = HttpHeader::New();
     header->name = "Content-Length";
     header->value = base::StringPrintf("%" PRId64, file_size);
     response->headers[0] = header.Pass();
   }
+  response->mime_type = String::From(MimeType());
   common::CopyFromFile(path_, data_pipe.producer_handle.Pass(), skip,
                        task_runner, base::Bind(&IgnoreResult));
   return response.Pass();
 }
 
 void LocalFetcher::AsPath(
     base::TaskRunner* task_runner,
     base::Callback<void(const base::FilePath&, bool)> callback) {
   // Async for consistency with network case.
   base::MessageLoop::current()->PostTask(
       FROM_HERE, base::Bind(callback, path_, base::PathExists(path_)));
 }
 
 std::string LocalFetcher::MimeType() {
-  return "";
+  // TODO(msw): Expand support; use net::GetMimeTypeFromExtension or similar.
+  std::string extension(base::FilePath(path_.Extension()).AsUTF8Unsafe());
+  if (base::EqualsCaseInsensitiveASCII(extension, ".html") ||
+      base::EqualsCaseInsensitiveASCII(extension, ".htm") ||
+      base::EqualsCaseInsensitiveASCII(extension, ".shtml") ||
+      base::EqualsCaseInsensitiveASCII(extension, ".shtm") ||
+      base::EqualsCaseInsensitiveASCII(extension, ".ehtml")) {
+    return "text/html";
+  }
+  return std::string();
 }
 
 bool LocalFetcher::HasMojoMagic() {
   std::string magic;
   ReadFileToString(path_, &magic, strlen(kMojoMagic));
   return magic == kMojoMagic;
 }
 
 bool LocalFetcher::PeekFirstLine(std::string* line) {
   std::string start_of_file;
   ReadFileToString(path_, &start_of_file, kMaxShebangLength);
   size_t return_position = start_of_file.find('\n');
   if (return_position == std::string::npos)
     return false;
   *line = start_of_file.substr(0, return_position + 1);
   return true;
 }
 
 }  // namespace shell
 }  // namespace mojo