Function TestConfigWithSamplingHook

config_test.go:161–203

(t *testing.T)

}

func TestConfigWithSamplingHook(t *testing.T) {
	shook, dcount, scount := makeSamplerCountingHook()
	cfg := Config{
		Level:       NewAtomicLevelAt(InfoLevel),
		Development: false,
		Sampling: &SamplingConfig{
			Initial:    100,
			Thereafter: 100,
			Hook:       shook,
		},
		Encoding:         "json",
		EncoderConfig:    NewProductionEncoderConfig(),
		OutputPaths:      []string{"stderr"},
		ErrorOutputPaths: []string{"stderr"},
	}
	expectRe := `{"level":"info","caller":"[a-z0-9_-]+/config_test.go:\d+","msg":"info","k":"v","z":"zz"}` + "\n" +
		`{"level":"warn","caller":"[a-z0-9_-]+/config_test.go:\d+","msg":"warn","k":"v","z":"zz"}` + "\n"
	expectDropped := 99  // 200 - 100 initial - 1 thereafter
	expectSampled := 103 // 2 from initial + 100 + 1 thereafter

	logOut := filepath.Join(t.TempDir(), "test.log")
	cfg.OutputPaths = []string{logOut}
	cfg.EncoderConfig.TimeKey = "" // no timestamps in tests
	cfg.InitialFields = map[string]interface{}{"z": "zz", "k": "v"}

	logger, err := cfg.Build()
	require.NoError(t, err, "Unexpected error constructing logger.")

	logger.Debug("debug")
	logger.Info("info")
	logger.Warn("warn")

	byteContents, err := os.ReadFile(logOut)
	require.NoError(t, err, "Couldn't read log contents from temp file.")
	logs := string(byteContents)
	assert.Regexp(t, expectRe, logs, "Unexpected log output.")

	for i := 0; i < 200; i++ {
		logger.Info("sampling")
	}
	assert.Equal(t, int64(expectDropped), dcount.Load())
	assert.Equal(t, int64(expectSampled), scount.Load())
}