WebUI: Serve mime type in Content-Type header

BUG=315513

Review URL: https://codereview.chromium.org/61783002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233552 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 33 insertions, 0 deletions

diff --git a/chrome/browser/ui/webui/devtools_ui.cc b/chrome/browser/ui/webui/devtools_ui.cc
index f755272..df95d3b 100644
--- a/chrome/browser/ui/webui/devtools_ui.cc
+++ b/chrome/browser/ui/webui/devtools_ui.cc
@@ -183,6 +183,10 @@ class DevToolsDataSource : public content::URLDataSource {
     return false;
   }
 
+  virtual bool ShouldServeMimeTypeAsContentTypeHeader() const OVERRIDE {
+    return true;
+  }
+
  private:
   virtual ~DevToolsDataSource() {}
   scoped_refptr<net::URLRequestContextGetter> request_context_;
diff --git a/content/browser/webui/url_data_manager_backend.cc b/content/browser/webui/url_data_manager_backend.cc
index 1bcbdb7..1e37800 100644
--- a/content/browser/webui/url_data_manager_backend.cc
+++ b/content/browser/webui/url_data_manager_backend.cc
@@ -17,6 +17,7 @@
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
 #include "content/browser/fileapi/chrome_blob_storage_context.h"
 #include "content/browser/histogram_internals_request_job.h"
 #include "content/browser/net/view_blob_internals_job_factory.h"
@@ -147,6 +148,10 @@ class URLRequestChromeJob : public net::URLRequestJob,
     deny_xframe_options_ = deny_xframe_options;
   }
 
+  void set_send_content_type_header(bool send_content_type_header) {
+    send_content_type_header_ = send_content_type_header;
+  }
+
   // Returns true when job was generated from an incognito profile.
   bool is_incognito() const {
     return is_incognito_;
@@ -188,6 +193,9 @@ class URLRequestChromeJob : public net::URLRequestJob,
   // If true, sets  the "X-Frame-Options: DENY" header.
   bool deny_xframe_options_;
 
+  // If true, sets the "Content-Type: <mime-type>" header.
+  bool send_content_type_header_;
+
   // True when job is generated from an incognito profile.
   const bool is_incognito_;
 
@@ -211,6 +219,7 @@ URLRequestChromeJob::URLRequestChromeJob(net::URLRequest* request,
       content_security_policy_object_source_("object-src 'none';"),
       content_security_policy_frame_source_("frame-src 'none';"),
       deny_xframe_options_(true),
+      send_content_type_header_(false),
       is_incognito_(is_incognito),
       backend_(backend),
       weak_factory_(this) {
@@ -267,6 +276,13 @@ void URLRequestChromeJob::GetResponseInfo(net::HttpResponseInfo* info) {
 
   if (!allow_caching_)
     info->headers->AddHeader("Cache-Control: no-cache");
+
+  if (send_content_type_header_ && !mime_type_.empty()) {
+    std::string content_type =
+        base::StringPrintf("%s:%s", net::HttpRequestHeaders::kContentType,
+                           mime_type_.c_str());
+    info->headers->AddHeader(content_type);
+  }
 }
 
 void URLRequestChromeJob::MimeTypeAvailable(const std::string& mime_type) {
@@ -511,6 +527,8 @@ bool URLDataManagerBackend::StartRequest(const net::URLRequest* request,
       source->source()->GetContentSecurityPolicyFrameSrc());
   job->set_deny_xframe_options(
       source->source()->ShouldDenyXFrameOptions());
+  job->set_send_content_type_header(
+      source->source()->ShouldServeMimeTypeAsContentTypeHeader());
 
   // Look up additional request info to pass down.
   int render_process_id = -1;
diff --git a/content/public/browser/url_data_source.cc b/content/public/browser/url_data_source.cc
index 669f5c8..d9506f5 100644
--- a/content/public/browser/url_data_source.cc
+++ b/content/public/browser/url_data_source.cc
@@ -52,4 +52,8 @@ bool URLDataSource::ShouldServiceRequest(const net::URLRequest* request) const {
   return false;
 }
 
+bool URLDataSource::ShouldServeMimeTypeAsContentTypeHeader() const {
+  return false;
+}
+
 }  // namespace content
diff --git a/content/public/browser/url_data_source.h b/content/public/browser/url_data_source.h
index d6ff1e0..d93e51e 100644
--- a/content/public/browser/url_data_source.h
+++ b/content/public/browser/url_data_source.h
@@ -108,6 +108,13 @@ class CONTENT_EXPORT URLDataSource {
   // WebUI scheme support for an embedder.
   virtual bool ShouldServiceRequest(const net::URLRequest* request) const;
 
+  // By default, Content-Type: header is not sent along with the response.
+  // To start sending mime type returned by GetMimeType in HTTP headers,
+  // return true. It is useful when tunneling response served from this data
+  // source programmatically. Or when AppCache is enabled for this source as it
+  // is for chrome-devtools.
+  virtual bool ShouldServeMimeTypeAsContentTypeHeader() const;
+
   // Called to inform the source that StartDataRequest() will be called soon.
   // Gives the source an opportunity to rewrite |path| to incorporate extra
   // information from the URLRequest prior to serving.