Add new API function: feedbackPrivate.readLogSource

chrome/browser/extensions/api/feedback_private/log_source_access_manager_chromeos_unittest.cc

Index: chrome/browser/extensions/api/feedback_private/log_source_access_manager_chromeos_unittest.cc
diff --git a/chrome/browser/extensions/api/feedback_private/log_source_access_manager_chromeos_unittest.cc b/chrome/browser/extensions/api/feedback_private/log_source_access_manager_chromeos_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..05780e1555c8375613469c88ff282600a6265769
--- /dev/null
+++ b/chrome/browser/extensions/api/feedback_private/log_source_access_manager_chromeos_unittest.cc
@@ -0,0 +1,159 @@
+// Copyright 2017 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 "chrome/browser/extensions/api/feedback_private/log_source_access_manager.h"
+
+#include "base/macros.h"
+#include "base/memory/ptr_util.h"
+#include "base/run_loop.h"
+#include "base/strings/stringprintf.h"
+#include "chrome/browser/extensions/api/feedback_private/log_source_resource.h"
+#include "chrome/browser/extensions/api/feedback_private/single_log_source_factory.h"
+#include "chrome/browser/extensions/extension_api_unittest.h"
+#include "extensions/browser/api/api_resource_manager.h"
+
+namespace extensions {
+
+namespace {
+
+using api::feedback_private::LOG_SOURCE_MESSAGES;
+using api::feedback_private::LOG_SOURCE_UILATEST;
+using api::feedback_private::ReadLogSourceResult;
+using api::feedback_private::ReadLogSourceParams;
+using system_logs::SingleLogSource;
+using SupportedSource = system_logs::SingleLogSource::SupportedSource;
+
+std::unique_ptr<KeyedService> ApiResourceManagerTestFactory(
+    content::BrowserContext* context) {
+  return base::MakeUnique<ApiResourceManager<LogSourceResource>>(context);
+}
+
+// Dummy function used as a callback for FetchFromSource().
+void OnFetchedFromSource(const ReadLogSourceResult& result) {}
+
+// A dummy SingleLogSource that does not require real system logs to be
+// available during testing. Always returns an empty result.
+class EmptySingleLogSource : public SingleLogSource {
+ public:
+  explicit EmptySingleLogSource(SupportedSource type) : SingleLogSource(type) {}
+
+  ~EmptySingleLogSource() override = default;
+
+  void Fetch(const system_logs::SysLogsSourceCallback& callback) override {
+    system_logs::SystemLogsResponse* result_map =
+        new system_logs::SystemLogsResponse;
+    result_map->emplace("", "");
+
+    // Do not directly pass the result to the callback, because that's not how
+    // log sources actually work. Instead, simulate the asynchronous operation
+    // of a SingleLogSource by invoking the callback separately.
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(callback, base::Owned(result_map)));
+  }
+
+  // Instantiates a new instance of this class. Does not retain ownership. Used
+  // to create a Callback that can be used to override the default behavior of
+  // SingleLogSourceFactory.
+  static std::unique_ptr<SingleLogSource> Create(SupportedSource type) {
+    return base::MakeUnique<EmptySingleLogSource>(type);
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(EmptySingleLogSource);
+};
+
+}  // namespace
+
+class LogSourceAccessManagerTest : public ExtensionApiUnittest {
+ public:
+  LogSourceAccessManagerTest()
+      : create_callback_(base::Bind(&EmptySingleLogSource::Create)) {}
+  ~LogSourceAccessManagerTest() override {}
+
+  void SetUp() override {
+    ExtensionApiUnittest::SetUp();
+
+    // The ApiResourceManager used for LogSourceResource is destroyed every time
+    // a unit test finishes, during TearDown(). There is no way to re-create it
+    // normally. The below code forces it to be re-created during SetUp(), so
+    // that there is always a valid ApiResourceManager<LogSourceResource> when
+    // subsequent unit tests are running.
+    ApiResourceManager<LogSourceResource>::GetFactoryInstance()
+        ->SetTestingFactoryAndUse(profile(), ApiResourceManagerTestFactory);
+
+    SingleLogSourceFactory::SetForTesting(&create_callback_);
+  }
+
+  void TearDown() override {
+    SingleLogSourceFactory::SetForTesting(nullptr);
+    LogSourceAccessManager::SetRateLimitingTimeoutForTesting(nullptr);
+
+    ExtensionApiUnittest::TearDown();
+  }
+
+ private:
+  // Passed to SingleLogSourceFactory so that the API can create an instance of
+  // TestSingleLogSource for testing.
+  SingleLogSourceFactory::CreateCallback create_callback_;
+
+  DISALLOW_COPY_AND_ASSIGN(LogSourceAccessManagerTest);
+};
+
+TEST_F(LogSourceAccessManagerTest, MaxNumberOfOpenLogSources) {
+  const base::TimeDelta timeout(base::TimeDelta::FromMilliseconds(0));
+  LogSourceAccessManager::SetRateLimitingTimeoutForTesting(&timeout);
+
+  LogSourceAccessManager manager(profile());
+  LogSourceAccessManager::ReadLogSourceCallback callback =
+      base::Bind(&OnFetchedFromSource);
+
+  int count = 0;
+
+  // Open 10 readers for LOG_SOURCE_MESSAGES.
+  ReadLogSourceParams messages_params;
+  messages_params.incremental = false;
+  messages_params.source = LOG_SOURCE_MESSAGES;
+  for (int i = 0; i < 10; ++i, ++count) {
+    EXPECT_TRUE(manager.FetchFromSource(
+        messages_params, base::StringPrintf("extension %d", count), callback))
+        << count;
+  }
+  EXPECT_EQ(10U, manager.GetNumActiveResourcesForSource(LOG_SOURCE_MESSAGES));
+  EXPECT_EQ(0U, manager.GetNumActiveResourcesForSource(LOG_SOURCE_UILATEST));
+
+  // Open 10 readers for LOG_SOURCE_UILATEST.
+  ReadLogSourceParams ui_latest_params;
+  ui_latest_params.incremental = false;
+  ui_latest_params.source = LOG_SOURCE_UILATEST;
+  for (int i = 0; i < 10; ++i, ++count) {
+    EXPECT_TRUE(manager.FetchFromSource(
+        ui_latest_params, base::StringPrintf("extension %d", count), callback))
+        << count;
+  }
+  EXPECT_EQ(10U, manager.GetNumActiveResourcesForSource(LOG_SOURCE_MESSAGES));
+  EXPECT_EQ(10U, manager.GetNumActiveResourcesForSource(LOG_SOURCE_UILATEST));
+
+  // Can't open more readers for LOG_SOURCE_MESSAGES.
+  for (int i = 0; i < 10; ++i, ++count) {
+    EXPECT_FALSE(manager.FetchFromSource(
+        messages_params, base::StringPrintf("extension %d", count), callback))
+        << count;
+  }
+  EXPECT_EQ(10U, manager.GetNumActiveResourcesForSource(LOG_SOURCE_MESSAGES));
+  EXPECT_EQ(10U, manager.GetNumActiveResourcesForSource(LOG_SOURCE_UILATEST));
+
+  // Can't open more readers for LOG_SOURCE_UILATEST.
+  for (int i = 0; i < 10; ++i, ++count) {
+    EXPECT_FALSE(manager.FetchFromSource(
+        ui_latest_params, base::StringPrintf("extension %d", count), callback))
+        << count;
+  }
+  EXPECT_EQ(10U, manager.GetNumActiveResourcesForSource(LOG_SOURCE_MESSAGES));
+  EXPECT_EQ(10U, manager.GetNumActiveResourcesForSource(LOG_SOURCE_UILATEST));
+
+  // Wait for all asynchronous operations to complete.
+  base::RunLoop().RunUntilIdle();
+}
+
+}  // namespace extensions