Move MimeTypeResourceHandler before ThrottlingResourceHandler

content/browser/loader/intercepting_resource_handler_unittest.cc

Index: content/browser/loader/intercepting_resource_handler_unittest.cc
diff --git a/content/browser/loader/mime_type_resource_handler_unittest.cc b/content/browser/loader/intercepting_resource_handler_unittest.cc
similarity index 55%
rename from content/browser/loader/mime_type_resource_handler_unittest.cc
rename to content/browser/loader/intercepting_resource_handler_unittest.cc
index 6bed3a84943e687afdae7da24ee34929042361b8..7c1086a99dbd7f2b1e337a91de13a1a61239b143 100644
--- a/content/browser/loader/mime_type_resource_handler_unittest.cc
+++ b/content/browser/loader/intercepting_resource_handler_unittest.cc
@@ -1,8 +1,8 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
+// Copyright 2016 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 "content/browser/loader/mime_type_resource_handler.h"
+#include "content/browser/loader/intercepting_resource_handler.h"
 
 #include <stdint.h>
 
@@ -48,9 +48,7 @@ class TestResourceHandler : public ResourceHandler {
     return false;
   }
 
-  bool OnWillStart(const GURL& url, bool* defer) override {
-    return false;
-  }
+  bool OnWillStart(const GURL& url, bool* defer) override { return false; }
 
   bool OnBeforeNetworkStart(const GURL& url, bool* defer) override {
     NOTREACHED();
@@ -71,23 +69,74 @@ class TestResourceHandler : public ResourceHandler {
 
   void OnResponseCompleted(const net::URLRequestStatus& status,
                            const std::string& security_info,
+                           bool* defer) override {}
+
+  void OnDataDownloaded(int bytes_downloaded) override { NOTREACHED(); }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TestResourceHandler);
+};
+
+class TestResourceHandlerWithBuffer : public ResourceHandler {
+ public:
+  TestResourceHandlerWithBuffer()
+      : ResourceHandler(nullptr), buffer_(new net::IOBuffer(2048)) {}
+  ~TestResourceHandlerWithBuffer() override {}
+
+  void SetController(ResourceController* controller) override {}
+
+  bool OnRequestRedirected(const net::RedirectInfo& redirect_info,
+                           ResourceResponse* response,
                            bool* defer) override {
+    NOTREACHED();
+    return false;
+  }
+
+  bool OnResponseStarted(ResourceResponse* response, bool* defer) override {
+    return true;
   }
 
-  void OnDataDownloaded(int bytes_downloaded) override {
+  bool OnWillStart(const GURL& url, bool* defer) override { return false; }
+
+  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override {
     NOTREACHED();
+    return false;
+  }
+
+  bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
+                  int* buf_size,
+                  int min_size) override {
+    *buf = buffer_;
+    *buf_size = 2048;
+    return true;
+  }
+
+  bool OnReadCompleted(int bytes_read, bool* defer) override {
+    DCHECK_LT(bytes_read, 2048);
+    return true;
   }
 
+  void OnResponseCompleted(const net::URLRequestStatus& status,
+                           const std::string& security_info,
+                           bool* defer) override {}
+
+  void OnDataDownloaded(int bytes_downloaded) override { NOTREACHED(); }
+
+  scoped_refptr<net::IOBuffer> buffer() { return buffer_; }
+
  private:
-  DISALLOW_COPY_AND_ASSIGN(TestResourceHandler);
+  scoped_refptr<net::IOBuffer> buffer_;
+  DISALLOW_COPY_AND_ASSIGN(TestResourceHandlerWithBuffer);
 };
 
 class TestResourceDispatcherHost : public ResourceDispatcherHostImpl {
  public:
-  explicit TestResourceDispatcherHost(bool stream_has_handler)
+  TestResourceDispatcherHost(bool stream_has_handler, bool use_buffer)
       : stream_has_handler_(stream_has_handler),
         intercepted_as_stream_(false),
-        intercepted_as_stream_count_(0) {}
+        intercepted_as_stream_count_(0),
+        last_resource_handler_(nullptr),
+        use_buffer_(use_buffer) {}
 
   bool intercepted_as_stream() const { return intercepted_as_stream_; }
 
@@ -95,7 +144,7 @@ class TestResourceDispatcherHost : public ResourceDispatcherHostImpl {
       net::URLRequest* request,
       bool is_content_initiated,
       bool must_download) override {
-    return std::unique_ptr<ResourceHandler>(new TestResourceHandler);
+    return CreateNewResourceHandler();
   }
 
   std::unique_ptr<ResourceHandler> MaybeInterceptAsStream(
@@ -106,9 +155,9 @@ class TestResourceDispatcherHost : public ResourceDispatcherHostImpl {
     intercepted_as_stream_count_++;
     if (stream_has_handler_) {
       intercepted_as_stream_ = true;
-      return std::unique_ptr<ResourceHandler>(new TestResourceHandler);
+      return CreateNewResourceHandler();
     } else {
-      return std::unique_ptr<ResourceHandler>();
+      return CreateNewResourceHandler();
     }
   }
 
@@ -116,7 +165,23 @@ class TestResourceDispatcherHost : public ResourceDispatcherHostImpl {
     return intercepted_as_stream_count_;
   }
 
+  TestResourceHandlerWithBuffer* last_resource_handler() const {
+    return last_resource_handler_;
+  }
+
  private:
+  std::unique_ptr<ResourceHandler> CreateNewResourceHandler() {
+    std::unique_ptr<ResourceHandler> new_resource_handler;
+    if (use_buffer_) {
+      new_resource_handler.reset(new TestResourceHandlerWithBuffer());
+      last_resource_handler_ = static_cast<TestResourceHandlerWithBuffer*>(
+          new_resource_handler.get());
+    } else {
+      new_resource_handler.reset(new TestResourceHandler());
+    }
+    return new_resource_handler;
+  }
+
   // Whether the URL request should be intercepted as a stream.
   bool stream_has_handler_;
 
@@ -126,14 +191,21 @@ class TestResourceDispatcherHost : public ResourceDispatcherHostImpl {
   // Count of number of times MaybeInterceptAsStream function get called in a
   // test.
   int intercepted_as_stream_count_;
+
+  // The last TestResourceHandlerWithBuffer created by this
+  // TestResourceDispatcherHost.
+  TestResourceHandlerWithBuffer* last_resource_handler_;
+
+  // Whether to create TestResourceHandlerWithBuffer instead of
+  // TestResourceHandlers.
+  bool use_buffer_;
 };
 
 class TestResourceDispatcherHostDelegate
     : public ResourceDispatcherHostDelegate {
  public:
   TestResourceDispatcherHostDelegate(bool must_download)
-      : must_download_(must_download) {
-  }
+      : must_download_(must_download) {}
 
   bool ShouldForceDownloadResource(const GURL& url,
                                    const std::string& mime_type) override {
@@ -148,17 +220,11 @@ class TestResourceController : public ResourceController {
  public:
   void Cancel() override {}
 
-  void CancelAndIgnore() override {
-    NOTREACHED();
-  }
+  void CancelAndIgnore() override { NOTREACHED(); }
 
-  void CancelWithError(int error_code) override {
-    NOTREACHED();
-  }
+  void CancelWithError(int error_code) override { NOTREACHED(); }
 
-  void Resume() override {
-    NOTREACHED();
-  }
+  void Resume() override { NOTREACHED(); }
 };
 
 class TestFakePluginService : public FakePluginService {
@@ -202,9 +268,9 @@ class TestFakePluginService : public FakePluginService {
   DISALLOW_COPY_AND_ASSIGN(TestFakePluginService);
 };
 
-class MimeTypeResourceHandlerTest : public testing::Test {
+class InterceptingResourceHandlerTest : public testing::Test {
  public:
-  MimeTypeResourceHandlerTest()
+  InterceptingResourceHandlerTest()
       : stream_has_handler_(false),
         plugin_available_(false),
         plugin_stale_(false) {}
@@ -223,11 +289,6 @@ class MimeTypeResourceHandlerTest : public testing::Test {
                                bool must_download,
                                ResourceType request_resource_type);
 
-  std::string TestAcceptHeaderSetting(ResourceType request_resource_type);
-  std::string TestAcceptHeaderSettingWithURLRequest(
-      ResourceType request_resource_type,
-      net::URLRequest* request);
-
  private:
   // Whether the URL request should be intercepted as a stream.
   bool stream_has_handler_;
@@ -237,7 +298,7 @@ class MimeTypeResourceHandlerTest : public testing::Test {
   TestBrowserThreadBundle thread_bundle_;
 };
 
-bool MimeTypeResourceHandlerTest::TestStreamIsIntercepted(
+bool InterceptingResourceHandlerTest::TestStreamIsIntercepted(
     bool allow_download,
     bool must_download,
     ResourceType request_resource_type) {
@@ -245,130 +306,46 @@ bool MimeTypeResourceHandlerTest::TestStreamIsIntercepted(
   std::unique_ptr<net::URLRequest> request(context.CreateRequest(
       GURL("http://www.google.com"), net::DEFAULT_PRIORITY, nullptr));
   bool is_main_frame = request_resource_type == RESOURCE_TYPE_MAIN_FRAME;
-  ResourceRequestInfo::AllocateForTesting(
-      request.get(),
-      request_resource_type,
-      nullptr,          // context
-      0,                // render_process_id
-      0,                // render_view_id
-      0,                // render_frame_id
-      is_main_frame,    // is_main_frame
-      false,            // parent_is_main_frame
-      allow_download,   // allow_download
-      true,             // is_async
-      false);           // is_using_lofi
-
-  TestResourceDispatcherHost host(stream_has_handler_);
+  ResourceRequestInfo::AllocateForTesting(request.get(), request_resource_type,
+                                          nullptr,        // context
+                                          0,              // render_process_id
+                                          0,              // render_view_id
+                                          0,              // render_frame_id
+                                          is_main_frame,  // is_main_frame
+                                          false,  // parent_is_main_frame
+                                          allow_download,  // allow_download
+                                          true,            // is_async
+                                          false);          // is_using_lofi
+
+  TestResourceDispatcherHost host(stream_has_handler_, false);
   TestResourceDispatcherHostDelegate host_delegate(must_download);
   host.SetDelegate(&host_delegate);
 
   TestFakePluginService plugin_service(plugin_available_, plugin_stale_);
-  std::unique_ptr<ResourceHandler> mime_sniffing_handler(
-      new MimeTypeResourceHandler(
+  std::unique_ptr<ResourceHandler> intercepting_handler(
+      new InterceptingResourceHandler(
           std::unique_ptr<ResourceHandler>(new TestResourceHandler()), &host,
           &plugin_service, request.get()));
+
   TestResourceController resource_controller;
-  mime_sniffing_handler->SetController(&resource_controller);
+  intercepting_handler->SetController(&resource_controller);
 
   scoped_refptr<ResourceResponse> response(new ResourceResponse);
   // The MIME type isn't important but it shouldn't be empty.
   response->head.mime_type = "application/pdf";
 
   bool defer = false;
-  mime_sniffing_handler->OnResponseStarted(response.get(), &defer);
+  intercepting_handler->OnResponseStarted(response.get(), &defer);
 
   content::RunAllPendingInMessageLoop();
   EXPECT_LT(host.intercepted_as_stream_count(), 2);
   return host.intercepted_as_stream();
 }
 
-std::string MimeTypeResourceHandlerTest::TestAcceptHeaderSetting(
-    ResourceType request_resource_type) {
-  net::URLRequestContext context;
-  std::unique_ptr<net::URLRequest> request(context.CreateRequest(
-      GURL("http://www.google.com"), net::DEFAULT_PRIORITY, nullptr));
-  return TestAcceptHeaderSettingWithURLRequest(
-      request_resource_type, request.get());
-}
-
-std::string MimeTypeResourceHandlerTest::TestAcceptHeaderSettingWithURLRequest(
-    ResourceType request_resource_type,
-    net::URLRequest* request) {
-  bool is_main_frame = request_resource_type == RESOURCE_TYPE_MAIN_FRAME;
-  ResourceRequestInfo::AllocateForTesting(
-      request,
-      request_resource_type,
-      nullptr,          // context
-      0,                // render_process_id
-      0,                // render_view_id
-      0,                // render_frame_id
-      is_main_frame,    // is_main_frame
-      false,            // parent_is_main_frame
-      false,            // allow_download
-      true,             // is_async
-      false);           // is_using_lofi
-
-  TestResourceDispatcherHost host(stream_has_handler_);
-  TestResourceDispatcherHostDelegate host_delegate(false);
-  host.SetDelegate(&host_delegate);
-
-  std::unique_ptr<ResourceHandler> mime_sniffing_handler(
-      new MimeTypeResourceHandler(
-          std::unique_ptr<ResourceHandler>(new TestResourceHandler()), &host,
-          nullptr, request));
-
-  bool defer = false;
-  mime_sniffing_handler->OnWillStart(request->url(), &defer);
-  content::RunAllPendingInMessageLoop();
-
-  std::string accept_header;
-  request->extra_request_headers().GetHeader("Accept", &accept_header);
-  return accept_header;
-}
-
-// Test that the proper Accept: header is set based on the ResourceType
-TEST_F(MimeTypeResourceHandlerTest, AcceptHeaders) {
-  EXPECT_EQ(
-      "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,"
-          "*/*;q=0.8",
-      TestAcceptHeaderSetting(RESOURCE_TYPE_MAIN_FRAME));
-  EXPECT_EQ(
-      "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,"
-          "*/*;q=0.8",
-    TestAcceptHeaderSetting(RESOURCE_TYPE_SUB_FRAME));
-  EXPECT_EQ("text/css,*/*;q=0.1",
-      TestAcceptHeaderSetting(RESOURCE_TYPE_STYLESHEET));
-  EXPECT_EQ("*/*",
-      TestAcceptHeaderSetting(RESOURCE_TYPE_SCRIPT));
-  EXPECT_EQ("image/webp,image/*,*/*;q=0.8",
-      TestAcceptHeaderSetting(RESOURCE_TYPE_IMAGE));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_FONT_RESOURCE));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_SUB_RESOURCE));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_OBJECT));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_MEDIA));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_WORKER));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_SHARED_WORKER));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_PREFETCH));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_FAVICON));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_XHR));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_PING));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_SERVICE_WORKER));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_CSP_REPORT));
-  EXPECT_EQ("*/*", TestAcceptHeaderSetting(RESOURCE_TYPE_PLUGIN_RESOURCE));
-
-  // Ensure that if an Accept header is already set, it is not overwritten.
-  net::URLRequestContext context;
-  std::unique_ptr<net::URLRequest> request(context.CreateRequest(
-      GURL("http://www.google.com"), net::DEFAULT_PRIORITY, nullptr));
-  request->SetExtraRequestHeaderByName("Accept", "*", true);
-  EXPECT_EQ("*",
-      TestAcceptHeaderSettingWithURLRequest(RESOURCE_TYPE_XHR, request.get()));
-}
-
 // Test that stream requests are correctly intercepted under the right
 // circumstances. Test is not relevent when plugins are disabled.
 #if defined(ENABLE_PLUGINS)
-TEST_F(MimeTypeResourceHandlerTest, StreamHandling) {
+TEST_F(InterceptingResourceHandlerTest, StreamHandling) {
   bool allow_download;
   bool must_download;
   ResourceType resource_type;
@@ -432,12 +409,6 @@ TEST_F(MimeTypeResourceHandlerTest, StreamHandling) {
   EXPECT_FALSE(
       TestStreamIsIntercepted(allow_download, must_download, resource_type));
 
-  allow_download = true;
-  must_download = false;
-  resource_type = RESOURCE_TYPE_MAIN_FRAME;
-  EXPECT_FALSE(
-      TestStreamIsIntercepted(allow_download, must_download, resource_type));
-
   // Test the cases where the stream handled by MaybeInterceptAsStream
   // with plugin not available. This is the case when intercepting streams for
   // the streamsPrivate extensions API.
@@ -461,6 +432,116 @@ TEST_F(MimeTypeResourceHandlerTest, StreamHandling) {
 }
 #endif
 
+// Tests that the data received is transmitted to the newly created
+// ResourceHandler.
+TEST_F(InterceptingResourceHandlerTest, ResponseBodyHandling) {
+  net::URLRequestContext context;
+  std::unique_ptr<net::URLRequest> request(context.CreateRequest(
+      GURL("http://www.google.com"), net::DEFAULT_PRIORITY, nullptr));
+  ResourceRequestInfo::AllocateForTesting(request.get(),
+                                          RESOURCE_TYPE_MAIN_FRAME,
+                                          nullptr,  // context
+                                          0,        // render_process_id
+                                          0,        // render_view_id
+                                          0,        // render_frame_id
+                                          true,     // is_main_frame
+                                          false,    // parent_is_main_frame
+                                          true,     // allow_download
+                                          true,     // is_async
+                                          false);   // is_using_lofi
+
+  TestResourceDispatcherHost host(false, true);
+  TestResourceDispatcherHostDelegate host_delegate(false);
+  host.SetDelegate(&host_delegate);
+
+  std::unique_ptr<ResourceHandler> old_handler(
+      new TestResourceHandlerWithBuffer());
+  scoped_refptr<net::IOBuffer> old_buffer =
+      static_cast<TestResourceHandlerWithBuffer*>(old_handler.get())->buffer();
+  TestFakePluginService plugin_service(false, false);
+  std::unique_ptr<ResourceHandler> intercepting_handler(
+      new InterceptingResourceHandler(std::move(old_handler), &host,
+                                      &plugin_service, request.get()));
+
+  TestResourceController resource_controller;
+  intercepting_handler->SetController(&resource_controller);
+
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  // The MIME type isn't important but it shouldn't be empty.
+  response->head.mime_type = "application/pdf";
+
+  // Simulate the MimeSniffingResourceHandler buffering the data.
+  scoped_refptr<net::IOBuffer> read_buffer;
+  int buf_size = 0;
+  intercepting_handler->OnWillRead(&read_buffer, &buf_size, -1);
+
+  char data[] = "The data";
+  CHECK_EQ(read_buffer.get(), old_buffer.get());
+  memcpy(read_buffer->data(), data, sizeof(data));
+
+  // The response is received. A new ResourceHandler should be created to
+  // handle the download.
+  bool defer = false;
+  intercepting_handler->OnResponseStarted(response.get(), &defer);
+  EXPECT_FALSE(defer);
+  TestResourceHandlerWithBuffer* new_handler = host.last_resource_handler();
+  CHECK(new_handler);
+
+  // It should not have received the download data yet.
+  EXPECT_FALSE(!memcmp(data, new_handler->buffer()->data(), sizeof(data)));
+
+  // The read is replayed by the MimeSniffingResourceHandler. The data should
+  // have been received by the new handler.
+  intercepting_handler->OnReadCompleted(sizeof(data), &defer);
+  EXPECT_FALSE(defer);
+  EXPECT_TRUE(!memcmp(data, new_handler->buffer()->data(), sizeof(data)));
+}
+
+// Tests that 304s do not trigger a change in handlers.
+TEST_F(InterceptingResourceHandlerTest, 304Handling) {
+  net::URLRequestContext context;
+  std::unique_ptr<net::URLRequest> request(context.CreateRequest(
+      GURL("http://www.google.com"), net::DEFAULT_PRIORITY, nullptr));
+  ResourceRequestInfo::AllocateForTesting(request.get(),
+                                          RESOURCE_TYPE_MAIN_FRAME,
+                                          nullptr,  // context
+                                          0,        // render_process_id
+                                          0,        // render_view_id
+                                          0,        // render_frame_id
+                                          true,     // is_main_frame
+                                          false,    // parent_is_main_frame
+                                          true,     // allow_download
+                                          true,     // is_async
+                                          false);   // is_using_lofi
+
+  TestResourceDispatcherHost host(false, true);
+  TestResourceDispatcherHostDelegate host_delegate(false);
+  host.SetDelegate(&host_delegate);
+
+  TestFakePluginService plugin_service(false, false);
+  std::unique_ptr<ResourceHandler> intercepting_handler(
+      new InterceptingResourceHandler(
+          std::unique_ptr<ResourceHandler>(new TestResourceHandler()), &host,
+          &plugin_service, request.get()));
+
+  TestResourceController resource_controller;
+  intercepting_handler->SetController(&resource_controller);
+
+  // Simulate a 304 response.
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
+  // The MIME type isn't important but it shouldn't be empty.
+  response->head.mime_type = "application/pdf";
+  response->head.headers = new net::HttpResponseHeaders("HTTP/1.x 304 OK");
+
+  // The response is received. No new ResourceHandler should be created to
+  // handle the download.
+  bool defer = false;
+  intercepting_handler->OnResponseStarted(response.get(), &defer);
+  EXPECT_FALSE(defer);
+  TestResourceHandlerWithBuffer* new_handler = host.last_resource_handler();
+  EXPECT_TRUE(!new_handler);
+}
+
 }  // namespace
 
 }  // namespace content