cpp-logger/test/file_appender_test.cxx

//
//  file_appender_test.cxx
//  logger_test
//
//  Created by Sam Jaffe on 4/13/19.
//

#include <cstdlib>
#include <fstream>
#include <gmock/gmock.h>

#include "resource_factory/prototype_factory.hpp"

#include "logger/exception.h"
#include "logger/log_manager.h"
#include "logger/properties.h"
#include "logger_impl.h"
#include "mock_logger.h"

class FileAppenderTest : public testing::Test {
protected:
  void SetUp() override;
  void TearDown() override;
  
  std::string filename() const { return data; }
  std::shared_ptr<logging::log_appender>
  get(logging::properties const &) const;
private:
  std::shared_ptr<StubLayout> playout;
  char data[24];
};

void FileAppenderTest::SetUp() {
  strncpy(data, "test_log_fileXXXXXX.log", sizeof(data));
  int fd = -1;
  if ((fd = mkstemps(data, 4)) != -1) {
    close(fd); // We'll open this elsewhere
  } else {
    throw std::runtime_error(strerror(errno));
  }
  playout.reset(new StubLayout);
}

void FileAppenderTest::TearDown() {
  playout.reset();
  remove(data);
  memset(data, 0, sizeof(data));
}

std::shared_ptr<logging::log_appender>
FileAppenderTest::get(logging::properties const & props) const {
  auto pappender = logging::appenders::instance().get("File", props);
  return std::make_shared<logging::log_appender>(pappender, playout);
}

TEST_F(FileAppenderTest, ThrowsIfNoFilename) {
  EXPECT_THROW(logging::appenders::instance().get("File", {}),
               logging::invalid_property_type);
}

std::string slurp(std::string const & filename) {
  std::ifstream in(filename);
  std::stringstream ss;
  ss << in.rdbuf();
  return ss.str();
}

TEST_F(FileAppenderTest, WritesFile) {
  using namespace logging;
  using namespace logging::property;
  properties props{_obj({
    {"filename", _v(filename())}
  })};
  
  using testing::Eq;
  logpacket pkt{{}, level::error, {}, {}, "This is a test message"};
  EXPECT_NO_THROW(get(props)->write(pkt));
  EXPECT_THAT(slurp(filename()), Eq("This is a test message"));
}

TEST_F(FileAppenderTest, WillNotLogBelowThreshold) {
  using namespace logging;
  using namespace logging::property;
  properties props{_obj({
    {"filename", _v(filename())}
  })};
  
  EXPECT_FALSE(get(props)->should_log(level::warn));
  EXPECT_TRUE(get(props)->should_log(level::error));
}

TEST_F(FileAppenderTest, AppendsToFile) {
  using namespace logging;
  using namespace logging::property;
  properties props{_obj({
    {"filename", _v(filename())}
  })};
  
  using testing::Eq;
  logpacket pkt{{}, level::error, {}, {}, "Test"};
  for (int i = 0; i < 2; ++i) {
    EXPECT_NO_THROW(get(props)->write(pkt));
  }
  EXPECT_THAT(slurp(filename()), Eq("TestTest"));
}

TEST_F(FileAppenderTest, OverwritesFileWithSetting) {
  using namespace logging;
  using namespace logging::property;
  properties props{_obj({
    {"filename", _v(filename())},
    {"fileAppend", _v(false)}
  })};
  
  using testing::Eq;
  logpacket pkt{{}, level::error, {}, {}, "Test"};
  for (int i = 0; i < 2; ++i) {
    EXPECT_NO_THROW(get(props)->write(pkt));
  }
  EXPECT_THAT(slurp(filename()), Eq("Test"));
}

TEST_F(FileAppenderTest, CanWriteBufferedData) {
  using namespace logging;
  using namespace logging::property;
  properties props{_obj({
    {"immediateFlush", _v(false)},
    {"filename", _v(filename())},
    {"bufferedIO", _v(true)},
    {"bufferSize", _v(256)}
  })};
  
  using testing::Eq;
  logpacket pkt{{}, level::error, {}, {}, "Test"};
  EXPECT_NO_THROW(get(props)->write(pkt));
  // We can't really test the results here, because the standard library is in
  // control of the actual writes...
}

TEST_F(FileAppenderTest, WillThrowIfCannotOpenFile) {
  using namespace logging;
  using namespace logging::property;
  properties props{_obj({
    {"filename", _v("./fake_directory_for_testing/file.log")}
  })};
  EXPECT_THROW(get(props), std::runtime_error);
}