add Datadog output

outputs/all/all.go

@@ -1,5 +1,6 @@
 package all
 
 import (
+	_ "github.com/influxdb/telegraf/outputs/datadog"
 	_ "github.com/influxdb/telegraf/outputs/influxdb"
 )

outputs/datadog/datadog.go

@@ -0,0 +1,155 @@
+package datadog
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+	"sort"
+
+	"github.com/influxdb/influxdb/client"
+	t "github.com/influxdb/telegraf"
+	"github.com/influxdb/telegraf/outputs"
+)
+
+type Datadog struct {
+	Apikey  string
+	Timeout t.Duration
+
+	apiUrl string
+	client *http.Client
+}
+
+type TimeSeries struct {
+	Series []*Metric `json:"series"`
+}
+
+type Metric struct {
+	Metric string   `json:"metric"`
+	Points [1]Point `json:"points"`
+	Tags   []string `json:"tags,omitempty"`
+}
+
+type Point [2]float64
+
+const datadog_api = "https://app.datadoghq.com/api/v1/series"
+
+func NewDatadog(apiUrl string) *Datadog {
+	return &Datadog{
+		apiUrl: apiUrl,
+	}
+}
+
+func (d *Datadog) Connect() error {
+	if d.Apikey == "" {
+		return fmt.Errorf("apikey is a required field for datadog output")
+	}
+	d.client = &http.Client{
+		Timeout: d.Timeout.Duration,
+	}
+	return nil
+}
+
+func (d *Datadog) Write(bp client.BatchPoints) error {
+	if len(bp.Points) == 0 {
+		return nil
+	}
+	ts := TimeSeries{
+		Series: make([]*Metric, len(bp.Points)),
+	}
+	for index, pt := range bp.Points {
+		metric := &Metric{
+			Metric: pt.Measurement,
+			Tags:   buildTags(bp.Tags, pt.Tags),
+		}
+		if p, err := buildPoint(bp, pt); err == nil {
+			metric.Points[0] = p
+		}
+		ts.Series[index] = metric
+	}
+	tsBytes, err := json.Marshal(ts)
+	if err != nil {
+		return fmt.Errorf("unable to marshal TimeSeries, %s\n", err.Error())
+	}
+	req, err := http.NewRequest("POST", d.authenticatedUrl(), bytes.NewBuffer(tsBytes))
+	if err != nil {
+		return fmt.Errorf("unable to create http.Request, %s\n", err.Error())
+	}
+	req.Header.Add("Content-Type", "application/json")
+
+	resp, err := d.client.Do(req)
+	defer resp.Body.Close()
+	if err != nil {
+		return fmt.Errorf("error POSTing metrics, %s\n", err.Error())
+	}
+
+	if resp.StatusCode < 200 || resp.StatusCode > 209 {
+		return fmt.Errorf("received bad status code, %d\n", resp.StatusCode)
+	}
+
+	return nil
+}
+
+func (d *Datadog) authenticatedUrl() string {
+	q := url.Values{
+		"api_key": []string{d.Apikey},
+	}
+	return fmt.Sprintf("%s?%s", d.apiUrl, q.Encode())
+}
+
+func buildTags(bpTags map[string]string, ptTags map[string]string) []string {
+	tags := make([]string, (len(bpTags) + len(ptTags)))
+	index := 0
+	for k, v := range bpTags {
+		tags[index] = fmt.Sprintf("%s:%s", k, v)
+		index += 1
+	}
+	for k, v := range ptTags {
+		tags[index] = fmt.Sprintf("%s:%s", k, v)
+		index += 1
+	}
+	sort.Strings(tags)
+	return tags
+}
+
+func buildPoint(bp client.BatchPoints, pt client.Point) (Point, error) {
+	var p Point
+	if err := p.setValue(pt.Fields["value"]); err != nil {
+		return p, fmt.Errorf("unable to extract value from Fields, %s", err.Error())
+	}
+	if pt.Time.IsZero() {
+		p[0] = float64(bp.Time.Unix())
+	} else {
+		p[0] = float64(pt.Time.Unix())
+	}
+	return p, nil
+}
+
+func (p *Point) setValue(v interface{}) error {
+	switch d := v.(type) {
+	case int:
+		p[1] = float64(int(d))
+	case int32:
+		p[1] = float64(int32(d))
+	case int64:
+		p[1] = float64(int64(d))
+	case float32:
+		p[1] = float64(d)
+	case float64:
+		p[1] = float64(d)
+	default:
+		return fmt.Errorf("undeterminable type")
+	}
+	return nil
+}
+
+func (d *Datadog) Close() error {
+	return nil
+}
+
+func init() {
+	outputs.Add("datadog", func() outputs.Output {
+		return NewDatadog(datadog_api)
+	})
+}

outputs/datadog/datadog_test.go

@@ -0,0 +1,204 @@
+package datadog
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"reflect"
+	"testing"
+	"time"
+
+	"github.com/influxdb/influxdb/client"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+var (
+	fakeUrl    = "http://test.datadog.com"
+	fakeApiKey = "123456"
+)
+
+func fakeDatadog() *Datadog {
+	d := NewDatadog(fakeUrl)
+	d.Apikey = fakeApiKey
+	return d
+}
+
+func testData() client.BatchPoints {
+	var bp client.BatchPoints
+	bp.Time = time.Now()
+	bp.Tags = map[string]string{"tag1": "value1"}
+	bp.Points = []client.Point{
+		{
+			Fields: map[string]interface{}{"value": 1.0},
+		},
+	}
+	return bp
+}
+
+func TestUriOverride(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+		json.NewEncoder(w).Encode(`{"status":"ok"}`)
+	}))
+	defer ts.Close()
+
+	d := NewDatadog(ts.URL)
+	d.Apikey = "123456"
+	err := d.Connect()
+	require.NoError(t, err)
+	err = d.Write(testData())
+	require.NoError(t, err)
+}
+
+func TestBadStatusCode(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusInternalServerError)
+		json.NewEncoder(w).Encode(`{ 'errors': [
+    	'Something bad happened to the server.',
+    	'Your query made the server very sad.'
+  		]
+		}`)
+	}))
+	defer ts.Close()
+
+	d := NewDatadog(ts.URL)
+	d.Apikey = "123456"
+	err := d.Connect()
+	require.NoError(t, err)
+	err = d.Write(testData())
+	if err == nil {
+		t.Errorf("error expected but none returned")
+	} else {
+		require.EqualError(t, fmt.Errorf("received bad status code, 500\n"), err.Error())
+	}
+}
+
+func TestAuthenticatedUrl(t *testing.T) {
+	d := fakeDatadog()
+
+	authUrl := d.authenticatedUrl()
+	assert.EqualValues(t, fmt.Sprintf("%s?api_key=%s", fakeUrl, fakeApiKey), authUrl)
+}
+
+func TestBuildTags(t *testing.T) {
+	var tagtests = []struct {
+		bpIn    map[string]string
+		ptIn    map[string]string
+		outTags []string
+	}{
+		{
+			map[string]string{"one": "two"},
+			map[string]string{"three": "four"},
+			[]string{"one:two", "three:four"},
+		},
+		{
+			map[string]string{"aaa": "bbb"},
+			map[string]string{},
+			[]string{"aaa:bbb"},
+		},
+		{
+			map[string]string{},
+			map[string]string{},
+			[]string{},
+		},
+	}
+	for _, tt := range tagtests {
+		tags := buildTags(tt.bpIn, tt.ptIn)
+		if !reflect.DeepEqual(tags, tt.outTags) {
+			t.Errorf("\nexpected %+v\ngot %+v\n", tt.outTags, tags)
+		}
+	}
+}
+
+func TestBuildPoint(t *testing.T) {
+	var tagtests = []struct {
+		bpIn  client.BatchPoints
+		ptIn  client.Point
+		outPt Point
+		err   error
+	}{
+		{
+			client.BatchPoints{
+				Time: time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC),
+			},
+			client.Point{
+				Fields: map[string]interface{}{"value": 0.0},
+			},
+			Point{float64(time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC).Unix()), 0.0},
+			nil,
+		},
+		{
+			client.BatchPoints{},
+			client.Point{
+				Fields: map[string]interface{}{"value": 1.0},
+				Time:   time.Date(2010, time.December, 10, 23, 0, 0, 0, time.UTC),
+			},
+			Point{float64(time.Date(2010, time.December, 10, 23, 0, 0, 0, time.UTC).Unix()), 1.0},
+			nil,
+		},
+		{
+			client.BatchPoints{
+				Time: time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC),
+			},
+			client.Point{
+				Fields: map[string]interface{}{"value": 10},
+			},
+			Point{float64(time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC).Unix()), 10.0},
+			nil,
+		},
+		{
+			client.BatchPoints{
+				Time: time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC),
+			},
+			client.Point{
+				Fields: map[string]interface{}{"value": int32(112345)},
+			},
+			Point{float64(time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC).Unix()), 112345.0},
+			nil,
+		},
+		{
+			client.BatchPoints{
+				Time: time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC),
+			},
+			client.Point{
+				Fields: map[string]interface{}{"value": int64(112345)},
+			},
+			Point{float64(time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC).Unix()), 112345.0},
+			nil,
+		},
+		{
+			client.BatchPoints{
+				Time: time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC),
+			},
+			client.Point{
+				Fields: map[string]interface{}{"value": float32(11234.5)},
+			},
+			Point{float64(time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC).Unix()), 11234.5},
+			nil,
+		},
+		{
+			client.BatchPoints{
+				Time: time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC),
+			},
+			client.Point{
+				Fields: map[string]interface{}{"value": "11234.5"},
+			},
+			Point{float64(time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC).Unix()), 11234.5},
+			fmt.Errorf("unable to extract value from Fields, undeterminable type"),
+		},
+	}
+	for _, tt := range tagtests {
+		pt, err := buildPoint(tt.bpIn, tt.ptIn)
+		if err != nil && tt.err == nil {
+			t.Errorf("unexpected error, %+v\n", err)
+		}
+		if tt.err != nil && err == nil {
+			t.Errorf("expected an error (%s) but none returned", tt.err.Error())
+		}
+		if !reflect.DeepEqual(pt, tt.outPt) && tt.err == nil {
+			t.Errorf("\nexpected %+v\ngot %+v\n", tt.outPt, pt)
+		}
+	}
+}