Add new API function: feedbackPrivate.readLogSource

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

+// Copyright 2013 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/feedback_private_api.h"
+
+#include "base/macros.h"
+#include "base/message_loop/message_loop.h"
+#include "base/strings/stringprintf.h"
+#include "base/task_scheduler/post_task.h"
+#include "base/values.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 "extensions/browser/api_unittest.h"
+
+namespace extensions {
+
+namespace {
+
+using api::feedback_private::ReadLogSourceParams;
+using system_logs::SingleLogSource;
+using system_logs::SystemLogsResponse;
+using SupportedSource = system_logs::SingleLogSource::SupportedSource;
+
+// A dummy SingleLogSource that does not require real system logs to be
+// available during testing.
+class TestSingleLogSource : public SingleLogSource {
+ public:
+  explicit TestSingleLogSource(SupportedSource type)
+      : SingleLogSource(type), call_count_(0) {}
+
+  ~TestSingleLogSource() override {}
+
+  // Fetch() will return a single different string each time, in the following
+  // sequence: "a", "bb", "ccc", until a string of 26 z's. Will never return an
+  // empty result.
+  void Fetch(const system_logs::SysLogsSourceCallback& callback) override {
+    int count_modulus = call_count_ % kNumCharsToIterate;
+    std::string result(count_modulus + 1, kInitialChar + count_modulus);
+    CHECK_GT(result.size(), 0U);
+    ++call_count_;
+
+    SystemLogsResponse* result_map = new SystemLogsResponse;
+    result_map->emplace("", result);
+
+    // 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::PostDelayedTaskWithTraits(
+        FROM_HERE, base::TaskPriority::BACKGROUND,
+        base::Bind(callback, base::Owned(result_map)),
+        base::TimeDelta::FromMilliseconds(0));
+  }
+
+  // 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 SingleLogSource* Create(SupportedSource type) {
+    return new TestSingleLogSource(type);
+  }
+
+ private:
+  // Iterate over the whole lowercase alphabet, starting from 'a'.
+  const int kNumCharsToIterate = 26;
+  const char kInitialChar = 'a';
+
+  // Keep track of how many times Fetch() has been called, in order to determine
+  // its behavior each time.
+  int call_count_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestSingleLogSource);
+};
+
+}  // namespace
+
+class FeedbackApiUnittest : public ApiUnitTest {
+ public:
+  FeedbackApiUnittest()
+      : create_callback_(base::Bind(&TestSingleLogSource::Create)) {}
+  ~FeedbackApiUnittest() override {}
+
+  void SetUp() override {
+    ApiUnitTest::SetUp();
+
+    SingleLogSourceFactory::InitForTesting(&create_callback_);
+  }
+
+  void TearDown() override {
+    SingleLogSourceFactory::InitForTesting(nullptr);
+    LogSourceAccessManager::SetRateLimitingTimeoutForTesting(nullptr);
+
+    ApiUnitTest::TearDown();
+  }
+
+  // Runs the feedbackPrivate.readLogSource() function. See API function
+  // definition for argument descriptions. Attempts to interpret the result as
+  // the following ListValue:
+  //   [ int result_reader_id, [ string result_string ] ].
+  //
+  // Note that the second argument of the result is a list of strings, but the
+  // test class TestSingleLogSource always returns a list containing a single
+  // string.
+  //
+  // If the result does follow the above format, returns the reader ID and
+  // string value.
+  //
+  // Returns failure if the result does not conform to the above format, or is
+  // otherwise invalid.
+  testing::AssertionResult RunReadLogSourceFunction(
+      const ReadLogSourceParams& params,
+      int* result_reader_id,
+      std::string* result_string) {
+    std::unique_ptr<base::Value> result = RunFunctionAndReturnValue(
+        new FeedbackPrivateReadLogSourceFunction(),
+        ParamsToJSON(params));
+
+    if (!result)
+      return testing::AssertionFailure() << "No result";
+
+    base::ListValue* list = nullptr;
+    if (!result->GetAsList(&list)) {
+      return testing::AssertionFailure() << "Result was not a list.";
+    }
+    if (list->GetSize() != 2) {
+      return testing::AssertionFailure() << "Expected result length=2, actual="
+                                         << list->GetSize();
+    }
+    if (!list->GetInteger(0, result_reader_id)) {
+      return testing::AssertionFailure() << "Could not read argument 0 as int.";
+    }
+
+    base::ListValue* string_list = nullptr;
+    if (!list->GetList(1, &string_list)) {
+      return testing::AssertionFailure()
+          << "Could not read argument 1 as list.";
+    }
+    if (string_list->GetSize() != 1) {
+      return testing::AssertionFailure()
+          << "Argument 1 list expected to have size=1, actual="
+          << string_list->GetSize();
+    }
+    if (!string_list->GetString(0, result_string)) {
+      return testing::AssertionFailure()
+          << "Could not read argument 1 list's argument 0 as string.";
+    }
+
+    return testing::AssertionSuccess();
+  }
+
+ private:
+  // Converts |params| to a string containing a JSON dictionary within an
+  // argument list.
+  std::string ParamsToJSON(const ReadLogSourceParams& params) {
+    return base::StringPrintf(
+        "[{\"source\": \"%s\","
+        "  \"incremental\": %s,"
+        "  \"readerId\": %u}]",
+        api::feedback_private::ToString(params.source).c_str(),
+        params.incremental ? "true" : "false",
+        params.reader_id ? *params.reader_id : 0);
+  }
+
+  SingleLogSourceFactory::CreateCallback create_callback_;
+
+  DISALLOW_COPY_AND_ASSIGN(FeedbackApiUnittest);
+};
+
+TEST_F(FeedbackApiUnittest, ReadLogSourceNonIncremental) {
+  const base::TimeDelta timeout(base::TimeDelta::FromMilliseconds(0));
+  LogSourceAccessManager::SetRateLimitingTimeoutForTesting(&timeout);
+
+  ReadLogSourceParams params;
+  params.source = api::feedback_private::LOG_SOURCE_MESSAGES;
+  params.incremental = false;
+
+  // Test multiple non-incremental reads.
+  int result_reader_id = -1;
+  std::string result_string;
+  EXPECT_TRUE(
+      RunReadLogSourceFunction(params, &result_reader_id, &result_string));
+  EXPECT_EQ(0, result_reader_id);
+  EXPECT_EQ("a", result_string);
+
+  result_reader_id = -1;
+  result_string.clear();
+  EXPECT_TRUE(
+      RunReadLogSourceFunction(params, &result_reader_id, &result_string));
+  EXPECT_EQ(0, result_reader_id);
+  EXPECT_EQ("a", result_string);
+
+  result_reader_id = -1;
+  result_string.clear();
+  EXPECT_TRUE(
+      RunReadLogSourceFunction(params, &result_reader_id, &result_string));
+  EXPECT_EQ(0, result_reader_id);
+  EXPECT_EQ("a", result_string);
+}
+
+TEST_F(FeedbackApiUnittest, ReadLogSourceIncremental) {
+  const base::TimeDelta timeout(base::TimeDelta::FromMilliseconds(0));
+  LogSourceAccessManager::SetRateLimitingTimeoutForTesting(&timeout);
+
+  ReadLogSourceParams params;
+  params.source = api::feedback_private::LOG_SOURCE_MESSAGES;
+  params.incremental = true;
+
+  int result_reader_id = 0;
+  std::string result_string;
+  EXPECT_TRUE(
+      RunReadLogSourceFunction(params, &result_reader_id, &result_string));
+  EXPECT_EQ(1, result_reader_id);
+  EXPECT_EQ("a", result_string);
+  params.reader_id.reset(new int(result_reader_id));
+
+  EXPECT_TRUE(
+      RunReadLogSourceFunction(params, &result_reader_id, &result_string));
+  EXPECT_EQ(1, result_reader_id);
+  EXPECT_EQ("bb", result_string);
+
+  EXPECT_TRUE(
+      RunReadLogSourceFunction(params, &result_reader_id, &result_string));
+  EXPECT_EQ(1, result_reader_id);
+  EXPECT_EQ("ccc", result_string);
+
+  // End the incremental read.
+  params.incremental = false;
+  EXPECT_TRUE(
+      RunReadLogSourceFunction(params, &result_reader_id, &result_string));
+  EXPECT_EQ(0, result_reader_id);
+  EXPECT_EQ("dddd", result_string);
+
+  // Start a new incremental read.
+  params.incremental = true;
+  *params.reader_id = 0;
+  EXPECT_TRUE(
+      RunReadLogSourceFunction(params, &result_reader_id, &result_string));
+  // The reader ID should be incremented.
+  EXPECT_EQ(2, result_reader_id);
+  EXPECT_EQ("a", result_string);
+}
+
+} // namespace extensions