code cleanup

atom/browser/ui/webui/pdf_viewer_handler.cc

@@ -58,16 +58,17 @@ void PopulateStreamInfo(base::DictionaryValue* stream_info,
 }  // namespace
 
 PdfViewerHandler::PdfViewerHandler(const std::string& src)
-    : stream_(nullptr), original_url_(src), initialized_(false) {}
+    : stream_(nullptr), original_url_(src), initialized_(true) {}
 
 PdfViewerHandler::~PdfViewerHandler() {}
 
 void PdfViewerHandler::SetPdfResourceStream(content::StreamInfo* stream) {
   stream_ = stream;
-  if (initialized_) {
+  if (!initialized_) {
     auto list = base::MakeUnique<base::ListValue>();
     list->Set(0, std::move(initialize_callback_id_));
     Initialize(list.get());
+    initialized_ = true;
   }
 }
 
@@ -106,8 +107,6 @@ void PdfViewerHandler::Initialize(const base::ListValue* args) {
   CHECK(args->Get(0, &callback_id));
 
   if (stream_) {
-    initialized_ = false;
-
     AllowJavascript();
 
     std::unique_ptr<base::DictionaryValue> stream_info(
@@ -116,7 +115,7 @@ void PdfViewerHandler::Initialize(const base::ListValue* args) {
     ResolveJavascriptCallback(*callback_id, *stream_info);
   } else {
     initialize_callback_id_ = callback_id->CreateDeepCopy();
-    initialized_ = true;
+    initialized_ = false;
   }
 }
 

atom/browser/ui/webui/pdf_viewer_ui.cc

@@ -7,8 +7,10 @@
 #include <map>
 
 #include "atom/browser/atom_browser_context.h"
+#include "atom/browser/loader/layered_resource_handler.h"
 #include "atom/browser/ui/webui/pdf_viewer_handler.h"
 #include "atom/common/atom_constants.h"
+#include "base/sequenced_task_runner_helpers.h"
 #include "components/pdf/common/pdf_messages.h"
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/browser/loader/resource_request_info_impl.h"
@@ -98,15 +100,29 @@ class BundledDataSource : public content::URLDataSource {
   DISALLOW_COPY_AND_ASSIGN(BundledDataSource);
 };
 
-void RequestPdfResource(
+// Helper to convert from OnceCallback to Callback.
-    const GURL& url,
+template <typename T>
+void CallMigrationCallback(T callback,
+                           std::unique_ptr<content::StreamInfo> stream_info) {
+  std::move(callback).Run(std::move(stream_info));
+}
+
+}  // namespace
+
+class PdfViewerUI::ResourceRequester
+    : public base::RefCountedThreadSafe<ResourceRequester,
+                                        BrowserThread::DeleteOnIOThread>,
+      public atom::LayeredResourceHandler::Delegate {
+ public:
+  ResourceRequester(StreamResponseCallback cb)
+      : stream_response_cb_(std::move(cb)) {}
+
+  void StartRequest(const GURL& url,
                     const GURL& origin,
                     int render_process_id,
                     int render_view_id,
                     int render_frame_id,
-    content::ResourceContext* resource_context,
+                    content::ResourceContext* resource_context) {
-    base::Callback<void(std::unique_ptr<content::StreamInfo>)> callback,
-    atom::LayeredResourceHandler::Delegate* delegate) {
     DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
     const net::URLRequestContext* request_context =
@@ -129,16 +145,16 @@ void RequestPdfResource(
         new content::StreamResourceHandler(request.get(),
                                            stream_context->registry(), origin));
     info->set_is_stream(true);
-  std::unique_ptr<content::StreamInfo> stream_info(new content::StreamInfo);
+    stream_info_.reset(new content::StreamInfo);
-  stream_info->handle =
+    stream_info_->handle =
         static_cast<content::StreamResourceHandler*>(handler.get())
             ->stream()
             ->CreateHandle();
-  stream_info->original_url = request->url();
+    stream_info_->original_url = request->url();
 
     // Helper to fill stream response details.
     handler.reset(new atom::LayeredResourceHandler(request.get(),
-                                                 std::move(handler), delegate));
+                                                   std::move(handler), this));
 
     content::ResourceDispatcherHostImpl::Get()->BeginURLRequest(
         std::move(request), std::move(handler),
@@ -146,11 +162,39 @@ void RequestPdfResource(
         false,  // content_initiated (download specific)
         false,  // do_not_prompt_for_login (download specific)
         resource_context);
-
-  callback.Run(std::move(stream_info));
   }
 
-}  // namespace
+ protected:
+  // atom::LayeredResourceHandler::Delegate:
+  void OnResponseStarted(content::ResourceResponse* response) override {
+    DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+    auto resource_response_head = response->head;
+    auto headers = resource_response_head.headers;
+    auto mime_type = resource_response_head.mime_type;
+    if (headers.get())
+      stream_info_->response_headers =
+          new net::HttpResponseHeaders(headers->raw_headers());
+    stream_info_->mime_type = mime_type;
+
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(&CallMigrationCallback<StreamResponseCallback>,
+                   base::Passed(&stream_response_cb_),
+                   base::Passed(&stream_info_)));
+  }
+
+ private:
+  friend class base::RefCountedThreadSafe<ResourceRequester>;
+  friend struct BrowserThread::DeleteOnThread<BrowserThread::IO>;
+  friend class base::DeleteHelper<ResourceRequester>;
+  ~ResourceRequester() override {}
+
+  StreamResponseCallback stream_response_cb_;
+  std::unique_ptr<content::StreamInfo> stream_info_;
+
+  DISALLOW_COPY_AND_ASSIGN(ResourceRequester);
+};
 
 PdfViewerUI::PdfViewerUI(content::BrowserContext* browser_context,
                          content::WebUI* web_ui,
@@ -176,30 +220,11 @@ bool PdfViewerUI::OnMessageReceived(
   return handled;
 }
 
-void PdfViewerUI::OnPdfStreamResponseStarted(
-    scoped_refptr<net::HttpResponseHeaders> headers,
-    const std::string& mime_type) {
-  if (headers.get())
-    stream_->response_headers =
-        new net::HttpResponseHeaders(headers->raw_headers());
-  stream_->mime_type = mime_type;
-  pdf_handler_->SetPdfResourceStream(stream_.get());
-}
-
-void PdfViewerUI::OnResponseStarted(content::ResourceResponse* response) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
-
-  auto resource_response_head = response->head;
-  BrowserThread::PostTask(
-      BrowserThread::UI, FROM_HERE,
-      base::Bind(&PdfViewerUI::OnPdfStreamResponseStarted,
-                 base::Unretained(this), resource_response_head.headers,
-                 resource_response_head.mime_type));
-}
-
 void PdfViewerUI::OnPdfStreamCreated(
     std::unique_ptr<content::StreamInfo> stream) {
   stream_ = std::move(stream);
+  pdf_handler_->SetPdfResourceStream(stream_.get());
+  resource_requester_ = nullptr;
 }
 
 void PdfViewerUI::RenderFrameCreated(content::RenderFrameHost* rfh) {
@@ -208,13 +233,14 @@ void PdfViewerUI::RenderFrameCreated(content::RenderFrameHost* rfh) {
   int render_view_id = rfh->GetRenderViewHost()->GetRoutingID();
   auto resource_context =
       web_contents()->GetBrowserContext()->GetResourceContext();
+  auto callback =
+      base::BindOnce(&PdfViewerUI::OnPdfStreamCreated, base::Unretained(this));
+  resource_requester_ = new ResourceRequester(std::move(callback));
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
-      base::Bind(
+      base::Bind(&ResourceRequester::StartRequest, resource_requester_,
-          &RequestPdfResource, GURL(src_), GURL(kPdfViewerUIOrigin),
+                 GURL(src_), GURL(kPdfViewerUIOrigin), render_process_id,
-          render_process_id, render_view_id, render_frame_id, resource_context,
+                 render_view_id, render_frame_id, resource_context));
-          base::Bind(&PdfViewerUI::OnPdfStreamCreated, base::Unretained(this)),
-          this));
 }
 
 void PdfViewerUI::OnSaveURLAs(const GURL& url,

atom/browser/ui/webui/pdf_viewer_ui.h

@@ -7,7 +7,6 @@
 
 #include <string>
 
-#include "atom/browser/loader/layered_resource_handler.h"
 #include "base/macros.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_ui_controller.h"
@@ -15,21 +14,15 @@
 
 namespace content {
 class BrowserContext;
-class ResourceContext;
 struct StreamInfo;
 }
 
-namespace net {
-class HttpResponseHeaders;
-}
-
 namespace atom {
 
 class PdfViewerHandler;
 
 class PdfViewerUI : public content::WebUIController,
-                    public content::WebContentsObserver,
+                    public content::WebContentsObserver {
-                    public LayeredResourceHandler::Delegate {
  public:
   PdfViewerUI(content::BrowserContext* browser_context,
               content::WebUI* web_ui,
@@ -41,14 +34,12 @@ class PdfViewerUI : public content::WebUIController,
                          content::RenderFrameHost* render_frame_host) override;
   void RenderFrameCreated(content::RenderFrameHost* rfh) override;
 
-  // LayeredResourceHandler:
-  void OnResponseStarted(content::ResourceResponse* response) override;
-
  private:
+  using StreamResponseCallback =
+      base::OnceCallback<void(std::unique_ptr<content::StreamInfo>)>;
+  class ResourceRequester;
+
   void OnPdfStreamCreated(std::unique_ptr<content::StreamInfo> stream_info);
-  void OnPdfStreamResponseStarted(
-      scoped_refptr<net::HttpResponseHeaders> headers,
-      const std::string& mime_type);
   void OnSaveURLAs(const GURL& url, const content::Referrer& referrer);
 
   // Source URL from where the PDF originates.
@@ -56,6 +47,8 @@ class PdfViewerUI : public content::WebUIController,
 
   PdfViewerHandler* pdf_handler_;
 
+  scoped_refptr<ResourceRequester> resource_requester_;
+
   // Pdf Resource stream.
   std::unique_ptr<content::StreamInfo> stream_;