Add Serializer plugins, and 'file' output plugin

plugins/serializers/influx/influx.go

@@ -0,0 +1,12 @@
+package influx
+
+import (
+	"github.com/influxdata/telegraf"
+)
+
+type InfluxSerializer struct {
+}
+
+func (s *InfluxSerializer) Serialize(metric telegraf.Metric) ([]string, error) {
+	return []string{metric.String()}, nil
+}

plugins/serializers/influx/influx_test.go

@@ -0,0 +1,68 @@
+package influx
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/influxdata/telegraf"
+)
+
+func TestSerializeMetricFloat(t *testing.T) {
+	now := time.Now()
+	tags := map[string]string{
+		"cpu": "cpu0",
+	}
+	fields := map[string]interface{}{
+		"usage_idle": float64(91.5),
+	}
+	m, err := telegraf.NewMetric("cpu", tags, fields, now)
+	assert.NoError(t, err)
+
+	s := InfluxSerializer{}
+	mS, err := s.Serialize(m)
+	assert.NoError(t, err)
+
+	expS := []string{fmt.Sprintf("cpu,cpu=cpu0 usage_idle=91.5 %d", now.UnixNano())}
+	assert.Equal(t, expS, mS)
+}
+
+func TestSerializeMetricInt(t *testing.T) {
+	now := time.Now()
+	tags := map[string]string{
+		"cpu": "cpu0",
+	}
+	fields := map[string]interface{}{
+		"usage_idle": int64(90),
+	}
+	m, err := telegraf.NewMetric("cpu", tags, fields, now)
+	assert.NoError(t, err)
+
+	s := InfluxSerializer{}
+	mS, err := s.Serialize(m)
+	assert.NoError(t, err)
+
+	expS := []string{fmt.Sprintf("cpu,cpu=cpu0 usage_idle=90i %d", now.UnixNano())}
+	assert.Equal(t, expS, mS)
+}
+
+func TestSerializeMetricString(t *testing.T) {
+	now := time.Now()
+	tags := map[string]string{
+		"cpu": "cpu0",
+	}
+	fields := map[string]interface{}{
+		"usage_idle": "foobar",
+	}
+	m, err := telegraf.NewMetric("cpu", tags, fields, now)
+	assert.NoError(t, err)
+
+	s := InfluxSerializer{}
+	mS, err := s.Serialize(m)
+	assert.NoError(t, err)
+
+	expS := []string{fmt.Sprintf("cpu,cpu=cpu0 usage_idle=\"foobar\" %d", now.UnixNano())}
+	assert.Equal(t, expS, mS)
+}