package monitor import ( "fmt" "testing" "time" log "github.com/hashicorp/go-hclog" "github.com/stretchr/testify/require" ) func TestMonitor_Start(t *testing.T) { t.Parallel() require := require.New(t) logger := log.NewInterceptLogger(&log.LoggerOptions{ Level: log.Error, }) m := New(Config{ BufferSize: 512, Logger: logger, LoggerOptions: &log.LoggerOptions{ Level: log.Debug}, }) logCh := m.Start() defer m.Stop() logger.Debug("test log") for { select { case log := <-logCh: require.Contains(string(log), "[DEBUG] test log") return case <-time.After(3 * time.Second): t.Fatal("Expected to receive from log channel") } } } func TestMonitor_Stop(t *testing.T) { t.Parallel() require := require.New(t) logger := log.NewInterceptLogger(&log.LoggerOptions{ Level: log.Error, }) m := New(Config{ BufferSize: 512, Logger: logger, LoggerOptions: &log.LoggerOptions{ Level: log.Debug, }, }) logCh := m.Start() logger.Debug("test log") require.Eventually(func() bool { return len(logCh) == 1 }, 3*time.Second, 100*time.Millisecond, "expected logCh to have 1 log in it") m.Stop() // This log line should not be output to the log channel logger.Debug("After Stop") for { select { case log := <-logCh: if string(log) != "" { require.Contains(string(log), "[DEBUG] test log") } else { return } case <-time.After(3 * time.Second): t.Fatal("Expected to receive from log channel") } } } func TestMonitor_DroppedMessages(t *testing.T) { t.Parallel() require := require.New(t) logger := log.NewInterceptLogger(&log.LoggerOptions{ Level: log.Warn, }) mcfg := Config{ BufferSize: 5, Logger: logger, LoggerOptions: &log.LoggerOptions{ Level: log.Debug, }, } m := New(mcfg) doneCh := make(chan struct{}) defer close(doneCh) logCh := m.Start() // Overflow the configured buffer size before we attempt to receive from the // logCh. We choose (2*bufSize+1) to account for: // - buffer size of internal write channel // - buffer size of channel returned from Start() // - A message guaranteed to be dropped because all buffers are full for i := 0; i <= 2*mcfg.BufferSize+1; i++ { logger.Debug(fmt.Sprintf("test message %d", i)) } // Make sure we do not stop before the goroutines have time to process. require.Eventually(func() bool { return len(logCh) == mcfg.BufferSize }, 3*time.Second, 100*time.Millisecond, "expected logCh to have a full log buffer") dropped := m.Stop() // The number of dropped messages is non-deterministic, so we only assert // that we dropped at least 1. require.GreaterOrEqual(dropped, 1) } func TestMonitor_ZeroBufSizeDefault(t *testing.T) { t.Parallel() require := require.New(t) logger := log.NewInterceptLogger(&log.LoggerOptions{ Level: log.Error, }) m := New(Config{ BufferSize: 0, Logger: logger, LoggerOptions: &log.LoggerOptions{ Level: log.Debug, }, }) logCh := m.Start() defer m.Stop() logger.Debug("test log") // If we do not default the buffer size, the monitor will be unable to buffer // a log line. require.Eventually(func() bool { return len(logCh) == 1 }, 3*time.Second, 100*time.Millisecond, "expected logCh to have 1 log buffered") for { select { case log := <-logCh: require.Contains(string(log), "[DEBUG] test log") return case <-time.After(3 * time.Second): t.Fatal("Expected to receive from log channel") } } } func TestMonitor_WriteStopped(t *testing.T) { t.Parallel() require := require.New(t) logger := log.NewInterceptLogger(&log.LoggerOptions{ Level: log.Error, }) mwriter := &monitor{ logger: logger, doneCh: make(chan struct{}, 1), } mwriter.Stop() n, err := mwriter.Write([]byte("write after close")) require.Equal(n, 0) require.EqualError(err, "monitor stopped") }