aos/starter/subprocess_test.cc

#include "aos/starter/subprocess.h"

#include <signal.h>
#include <sys/types.h>

#include "gtest/gtest.h"

#include "aos/events/shm_event_loop.h"
#include "aos/testing/path.h"
#include "aos/testing/tmpdir.h"
#include "aos/util/file.h"

namespace aos::starter::testing {

class SubprocessTest : public ::testing::Test {
 protected:
  SubprocessTest() : shm_dir_(aos::testing::TestTmpDir() + "/aos") {
    FLAGS_shm_base = shm_dir_;

    // Nuke the shm dir:
    aos::util::UnlinkRecursive(shm_dir_);
  }

  gflags::FlagSaver flag_saver_;
  std::string shm_dir_;
};

TEST_F(SubprocessTest, CaptureOutputs) {
  const std::string config_file =
      ::aos::testing::ArtifactPath("aos/events/pingpong_config.json");

  aos::FlatbufferDetachedBuffer<aos::Configuration> config =
      aos::configuration::ReadConfig(config_file);
  aos::ShmEventLoop event_loop(&config.message());
  bool observed_stopped = false;
  Application echo_stdout(
      "echo", "echo", &event_loop, [&observed_stopped, &echo_stdout]() {
        if (echo_stdout.status() == aos::starter::State::STOPPED) {
          observed_stopped = true;
        }
      });
  ASSERT_FALSE(echo_stdout.autorestart());
  echo_stdout.set_args({"abcdef"});
  echo_stdout.set_capture_stdout(true);
  echo_stdout.set_capture_stderr(true);

  echo_stdout.Start();
  aos::TimerHandler *exit_timer =
      event_loop.AddTimer([&event_loop]() { event_loop.Exit(); });
  event_loop.OnRun([&event_loop, exit_timer]() {
    // Note: we are using the backup poll in this test to capture SIGCHLD.  This
    // runs at 1 hz, so make sure we let it run at least once.
    exit_timer->Schedule(event_loop.monotonic_now() +
                         std::chrono::milliseconds(1500));
  });

  event_loop.Run();

  ASSERT_EQ("abcdef\n", echo_stdout.GetStdout());
  ASSERT_TRUE(echo_stdout.GetStderr().empty());
  EXPECT_TRUE(observed_stopped);
  EXPECT_EQ(aos::starter::State::STOPPED, echo_stdout.status());

  observed_stopped = false;

  // Run again, the output should've been cleared.
  echo_stdout.set_args({"ghijkl"});
  echo_stdout.Start();
  event_loop.Run();
  ASSERT_EQ("ghijkl\n", echo_stdout.GetStdout());
  EXPECT_TRUE(observed_stopped);
}

TEST_F(SubprocessTest, CaptureStderr) {
  const std::string config_file =
      ::aos::testing::ArtifactPath("aos/events/pingpong_config.json");

  aos::FlatbufferDetachedBuffer<aos::Configuration> config =
      aos::configuration::ReadConfig(config_file);
  aos::ShmEventLoop event_loop(&config.message());
  bool observed_stopped = false;
  Application echo_stderr(
      "echo", "sh", &event_loop, [&observed_stopped, &echo_stderr]() {
        if (echo_stderr.status() == aos::starter::State::STOPPED) {
          observed_stopped = true;
        }
      });
  echo_stderr.set_args({"-c", "echo abcdef >&2"});
  echo_stderr.set_capture_stdout(true);
  echo_stderr.set_capture_stderr(true);

  echo_stderr.Start();
  // Note: we are using the backup poll in this test to capture SIGCHLD.  This
  // runs at 1 hz, so make sure we let it run at least once.
  event_loop.AddTimer([&event_loop]() { event_loop.Exit(); })
      ->Schedule(event_loop.monotonic_now() + std::chrono::milliseconds(1500));

  event_loop.Run();

  ASSERT_EQ("abcdef\n", echo_stderr.GetStderr());
  ASSERT_TRUE(echo_stderr.GetStdout().empty());
  ASSERT_TRUE(observed_stopped);
  ASSERT_EQ(aos::starter::State::STOPPED, echo_stderr.status());
}

TEST_F(SubprocessTest, UnactiveQuietFlag) {
  const std::string config_file =
      ::aos::testing::ArtifactPath("aos/events/pingpong_config.json");

  ::testing::internal::CaptureStderr();

  // Set up application without quiet flag active
  aos::FlatbufferDetachedBuffer<aos::Configuration> config =
      aos::configuration::ReadConfig(config_file);
  aos::ShmEventLoop event_loop(&config.message());
  bool observed_stopped = false;
  Application error_out(
      "false", "false", &event_loop,
      [&observed_stopped, &error_out]() {
        if (error_out.status() == aos::starter::State::STOPPED) {
          observed_stopped = true;
        }
      },
      Application::QuietLogging::kNo);
  ASSERT_FALSE(error_out.autorestart());

  error_out.Start();
  aos::TimerHandler *exit_timer =
      event_loop.AddTimer([&event_loop]() { event_loop.Exit(); });
  event_loop.OnRun([&event_loop, exit_timer]() {
    exit_timer->Schedule(event_loop.monotonic_now() +
                         std::chrono::milliseconds(1500));
  });

  event_loop.Run();

  // Ensure presence of logs without quiet flag
  std::string output = ::testing::internal::GetCapturedStderr();
  std::string expectedStart = "Failed to start 'false'";
  std::string expectedRun = "exited unexpectedly with status";

  ASSERT_TRUE(output.find(expectedStart) != std::string::npos ||
              output.find(expectedRun) != std::string::npos);
  EXPECT_TRUE(observed_stopped);
  EXPECT_EQ(aos::starter::State::STOPPED, error_out.status());
}

TEST_F(SubprocessTest, ActiveQuietFlag) {
  const std::string config_file =
      ::aos::testing::ArtifactPath("aos/events/pingpong_config.json");

  ::testing::internal::CaptureStderr();

  // Set up application with quiet flag active
  aos::FlatbufferDetachedBuffer<aos::Configuration> config =
      aos::configuration::ReadConfig(config_file);
  aos::ShmEventLoop event_loop(&config.message());
  bool observed_stopped = false;
  Application error_out(
      "false", "false", &event_loop,
      [&observed_stopped, &error_out]() {
        if (error_out.status() == aos::starter::State::STOPPED) {
          observed_stopped = true;
        }
      },
      Application::QuietLogging::kYes);
  ASSERT_FALSE(error_out.autorestart());

  error_out.Start();
  aos::TimerHandler *exit_timer =
      event_loop.AddTimer([&event_loop]() { event_loop.Exit(); });
  event_loop.OnRun([&event_loop, exit_timer]() {
    exit_timer->Schedule(event_loop.monotonic_now() +
                         std::chrono::milliseconds(1500));
  });

  event_loop.Run();

  // Ensure lack of logs with quiet flag
  ASSERT_TRUE(::testing::internal::GetCapturedStderr().empty());
  EXPECT_TRUE(observed_stopped);
  EXPECT_EQ(aos::starter::State::STOPPED, error_out.status());
}

// Tests that Nothing Bad™ happens if the event loop outlives the Application.
//
// Note that this is a bit of a hope test, as there is no guarantee that we
// will trigger a crash even if the resources tied to the event loop in the
// aos::Application aren't properly released.
TEST_F(SubprocessTest, ShortLivedApp) {
  const std::string config_file =
      ::aos::testing::ArtifactPath("aos/events/pingpong_config.json");

  aos::FlatbufferDetachedBuffer<aos::Configuration> config =
      aos::configuration::ReadConfig(config_file);
  aos::ShmEventLoop event_loop(&config.message());

  auto application =
      std::make_unique<Application>("sleep", "sleep", &event_loop, []() {});
  application->set_args({"10"});
  application->Start();
  pid_t pid = application->get_pid();

  int ticks = 0;
  aos::TimerHandler *exit_timer = event_loop.AddTimer([&event_loop, &ticks,
                                                       &application, pid]() {
    ticks++;
    if (application && application->status() == aos::starter::State::RUNNING) {
      // Kill the application, it will autorestart.
      kill(pid, SIGTERM);
      application.reset();
    }

    // event loop lives for longer.
    if (ticks >= 5) {
      // Now we exit.
      event_loop.Exit();
    }
  });

  event_loop.OnRun([&event_loop, exit_timer]() {
    exit_timer->Schedule(event_loop.monotonic_now(),
                         std::chrono::milliseconds(1000));
  });

  event_loop.Run();
}
}  // namespace aos::starter::testing