Limit to only 10 image requests per page in ResourceScheduler.

content/browser/loader/resource_scheduler_unittest.cc

 // Copyright (c) 2012 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/resource_scheduler.h"
 
+#include "base/memory/scoped_vector.h"
 #include "base/message_loop.h"
+#include "base/strings/string_number_conversions.h"
 #include "content/browser/browser_thread_impl.h"
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
+#include "content/browser/loader/resource_message_filter.h"
 #include "content/browser/loader/resource_request_info_impl.h"
+#include "content/common/resource_messages.h"
+#include "content/public/browser/resource_context.h"
 #include "content/public/browser/resource_controller.h"
 #include "content/public/browser/resource_throttle.h"
 #include "net/url_request/url_request.h"
 #include "net/url_request/url_request_test_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "webkit/glue/resource_type.h"
 
 namespace content {
 
 namespace {
@@ skipping 14 matching lines @@
   }
 
   bool started() const { return started_; }
 
   void Start() {
     bool deferred = false;
     throttle_->WillStartRequest(&deferred);
     started_ = !deferred;
   }
 
+  const net::URLRequest* url_request() const { return url_request_.get(); }
+
  protected:
   // ResourceController interface:
   virtual void Cancel() OVERRIDE {}
   virtual void CancelAndIgnore() OVERRIDE {}
   virtual void CancelWithError(int error_code) OVERRIDE {}
   virtual void Resume() OVERRIDE { started_ = true; }
 
  private:
   bool started_;
   scoped_ptr<ResourceThrottle> throttle_;
@@ skipping 13 matching lines @@
 
  private:
   virtual void Resume() OVERRIDE {
     TestRequest::Resume();
     request_to_cancel_.reset();
   }
 
   scoped_ptr<TestRequest> request_to_cancel_;
 };
 
+class TestResourceContext : public ResourceContext {

[willchan no longer on Chromium, 2013/03/19 20:53:53]

In the future, I suggest you follow the normal conventions here. See
http://stackoverflow.com/questions/346372/whats-the-difference-between-faking....

This is a Fake. Same as the other stuff below.

[James Simonsen, 2013/03/19 23:00:46]

Done.

+ private:
+  virtual net::HostResolver* GetHostResolver() OVERRIDE { return NULL; }
+  virtual net::URLRequestContext* GetRequestContext() OVERRIDE { return NULL; }
+};
+
+class TestURLRequestContextSelector
+    : public ResourceMessageFilter::URLRequestContextSelector {
+ private:
+  virtual net::URLRequestContext* GetRequestContext(
+      ResourceType::Type) OVERRIDE {
+    return NULL;
+  }
+};
+
+class TestResourceMessageFilter : public ResourceMessageFilter {
+ public:
+  TestResourceMessageFilter(int child_id)
+      : ResourceMessageFilter(child_id,
+                              PROCESS_TYPE_RENDERER,
+                              &context_,
+                              NULL  /* appcache_service */,
+                              NULL  /* blob_storage_context */,
+                              NULL  /* file_system_context */,
+                              new TestURLRequestContextSelector) {
+  }
+
+ private:
+  virtual ~TestResourceMessageFilter() {}
+
+  TestResourceContext context_;
+};
+
 class ResourceSchedulerTest : public testing::Test {
  protected:
   ResourceSchedulerTest()
-      : message_loop_(MessageLoop::TYPE_IO),
-        ui_thread_(BrowserThread::UI, &message_loop_) {
+      : next_request_id_(0),
+        message_loop_(MessageLoop::TYPE_IO),
+        ui_thread_(BrowserThread::UI, &message_loop_),
+        io_thread_(BrowserThread::IO, &message_loop_) {
     scheduler_.OnClientCreated(kChildId, kRouteId);
   }
 
   virtual ~ResourceSchedulerTest() {
     scheduler_.OnClientDeleted(kChildId, kRouteId);
   }
 
   scoped_ptr<net::URLRequest> NewURLRequest(const char* url,
                                             net::RequestPriority priority,
                                             int route_id = kRouteId) {
     scoped_ptr<net::URLRequest> url_request(
         context_.CreateRequest(GURL(url), NULL));
     url_request->set_priority(priority);
-    ResourceRequestInfo::AllocateForTesting(
-        url_request.get(), ResourceType::SUB_RESOURCE, NULL, kChildId,
-        route_id);
+    ResourceRequestInfoImpl* info = new ResourceRequestInfoImpl(
+        PROCESS_TYPE_RENDERER,             // process_type
+        kChildId,                          // child_id
+        route_id,                          // route_id
+        0,                                 // origin_pid
+        ++next_request_id_,                // request_id
+        false,                             // is_main_frame
+        0,                                 // frame_id
+        false,                             // parent_is_main_frame
+        0,                                 // parent_frame_id
+        ResourceType::SUB_RESOURCE,        // resource_type
+        PAGE_TRANSITION_LINK,              // transition_type
+        false,                             // is_download
+        true,                              // allow_download
+        false,                             // has_user_gesture
+        WebKit::WebReferrerPolicyDefault,  // referrer_policy
+        NULL,                              // context
+        true);                             // is_async
+    info->AssociateWithRequest(url_request.get());
     return url_request.Pass();
   }
 
   TestRequest* NewRequest(const char* url, net::RequestPriority priority,
                           int route_id = kRouteId) {

[willchan no longer on Chromium, 2013/03/19 20:53:53]

You should ditch these default arguments since they're against the style guide.
Instead I'd split this into two functions:
NewRequestWithRoute()
NewRequest() { NewRequestWithRoute(kRouteId); }

[James Simonsen, 2013/03/19 23:00:46]

Done.

     scoped_ptr<net::URLRequest> url_request(
         NewURLRequest(url, priority, route_id));
     scoped_ptr<ResourceThrottle> throttle(scheduler_.ScheduleRequest(
         kChildId, route_id, url_request.get()));
     TestRequest* request = new TestRequest(throttle.Pass(), url_request.Pass());
     request->Start();
     return request;
   }
 
+  void ChangeRequestPriority(TestRequest* request,
+                             net::RequestPriority new_priority) {
+    scoped_refptr<TestResourceMessageFilter> filter(
+        new TestResourceMessageFilter(kChildId));
+    const ResourceRequestInfoImpl* info = ResourceRequestInfoImpl::ForRequest(
+        request->url_request());
+    const GlobalRequestID& id = info->GetGlobalRequestID();
+    ResourceHostMsg_DidChangePriority msg(
+        kRouteId, id.request_id, new_priority);
+    bool ok = false;
+    rdh_.OnMessageReceived(msg, filter.get(), &ok);
+    EXPECT_TRUE(ok);
+  }
+
+  int next_request_id_;
   MessageLoop message_loop_;
   BrowserThreadImpl ui_thread_;
+  BrowserThreadImpl io_thread_;
   ResourceDispatcherHostImpl rdh_;
   ResourceScheduler scheduler_;
   net::TestURLRequestContext context_;
 };
 
 TEST_F(ResourceSchedulerTest, OneIsolatedLowRequest) {
   scoped_ptr<TestRequest> request(NewRequest("http://host/1", net::LOWEST));
   EXPECT_TRUE(request->started());
 }
 
@@ skipping 61 matching lines @@
   scoped_ptr<TestRequest> low4(NewRequest("http://host/low4", net::LOWEST));
 
   EXPECT_TRUE(high->started());
   EXPECT_FALSE(low2->started());
   high.reset();
   EXPECT_TRUE(low1->started());
   EXPECT_TRUE(low2->started());
   EXPECT_TRUE(low4->started());
 }
 
+TEST_F(ResourceSchedulerTest, LimitedNumberOfLowPriorityRequestsInFlight) {
+  // We only load low priority resources if there's a body.
+  scheduler_.OnWillInsertBody(kChildId, kRouteId);
+
+  // Throw in one high priority request to make sure that's not a factor.
+  scoped_ptr<TestRequest> high(NewRequest("http://host/high", net::HIGHEST));
+  EXPECT_TRUE(high->started());
+
+  const int kMaxNumLowPriorityRequestsPerClient = 10;  // Should match the .cc.
+  ScopedVector<TestRequest> lows;
+  for (int i = 0; i < kMaxNumLowPriorityRequestsPerClient; ++i) {
+    string url = "http://host/low" + base::IntToString(i);
+    lows.push_back(NewRequest(url.c_str(), net::LOWEST));
+    EXPECT_TRUE(lows[i]->started());
+  }
+
+  scoped_ptr<TestRequest> last(NewRequest("http://host/last", net::LOWEST));
+  EXPECT_FALSE(last->started());
+  high.reset();
+  EXPECT_FALSE(last->started());
+  lows.erase(lows.begin());
+  EXPECT_TRUE(last->started());
+}
+
+TEST_F(ResourceSchedulerTest, RaisePriorityAndStart) {
+  // Dummy to enforce scheduling.
+  scoped_ptr<TestRequest> high(NewRequest("http://host/high", net::HIGHEST));
+
+  scoped_ptr<TestRequest> request(NewRequest("http://host/req", net::LOWEST));
+  EXPECT_FALSE(request->started());
+
+  ChangeRequestPriority(request.get(), net::HIGHEST);
+  EXPECT_TRUE(request->started());
+}
+
+TEST_F(ResourceSchedulerTest, RaisePriorityInQueue) {
+  // Dummy to enforce scheduling.
+  scoped_ptr<TestRequest> high(NewRequest("http://host/high", net::HIGHEST));
+
+  scoped_ptr<TestRequest> request(NewRequest("http://host/req", net::IDLE));
+  scoped_ptr<TestRequest> idle(NewRequest("http://host/idle", net::IDLE));
+  EXPECT_FALSE(request->started());
+  EXPECT_FALSE(idle->started());
+
+  ChangeRequestPriority(request.get(), net::LOWEST);
+  EXPECT_FALSE(request->started());
+  EXPECT_FALSE(idle->started());
+
+  const int kMaxNumLowPriorityRequestsPerClient = 10;  // Should match the .cc.
+  ScopedVector<TestRequest> lows;
+  for (int i = 0; i < kMaxNumLowPriorityRequestsPerClient - 1; ++i) {
+    string url = "http://host/low" + base::IntToString(i);
+    lows.push_back(NewRequest(url.c_str(), net::LOWEST));
+  }
+
+  scheduler_.OnWillInsertBody(kChildId, kRouteId);
+  EXPECT_TRUE(request->started());
+  EXPECT_FALSE(idle->started());
+}
+
+TEST_F(ResourceSchedulerTest, LowerPriority) {
+  // Dummy to enforce scheduling.
+  scoped_ptr<TestRequest> high(NewRequest("http://host/high", net::HIGHEST));
+
+  scoped_ptr<TestRequest> request(NewRequest("http://host/req", net::LOWEST));
+  scoped_ptr<TestRequest> idle(NewRequest("http://host/idle", net::IDLE));
+  EXPECT_FALSE(request->started());
+  EXPECT_FALSE(idle->started());
+
+  ChangeRequestPriority(request.get(), net::IDLE);
+  EXPECT_FALSE(request->started());
+  EXPECT_FALSE(idle->started());
+
+  const int kMaxNumLowPriorityRequestsPerClient = 10;  // Should match the .cc.
+  ScopedVector<TestRequest> lows;
+  for (int i = 0; i < kMaxNumLowPriorityRequestsPerClient - 1; ++i) {
+    string url = "http://host/low" + base::IntToString(i);
+    lows.push_back(NewRequest(url.c_str(), net::LOWEST));
+  }
+
+  scheduler_.OnWillInsertBody(kChildId, kRouteId);
+  EXPECT_FALSE(request->started());
+  EXPECT_TRUE(idle->started());
+}
+
 }  // unnamed namespace
 
 }  // namespace content