Add Google Hangouts Chat notifier.

pkg/services/alerting/notifiers/googlechat.go

+package notifiers
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/grafana/grafana/pkg/bus"
+	"github.com/grafana/grafana/pkg/log"
+	m "github.com/grafana/grafana/pkg/models"
+	"github.com/grafana/grafana/pkg/services/alerting"
+	"github.com/grafana/grafana/pkg/setting"
+	"time"
+)
+
+func init() {
+	alerting.RegisterNotifier(&alerting.NotifierPlugin{
+		Type: "googlechat",
+		Name: "Google Hangouts Chat",
+		Description: "Sends notifications to Google Hangouts Chat via webhooks based on the official JSON message " +
+			"format (https://developers.google.com/hangouts/chat/reference/message-formats/).",
+		Factory: NewGoogleChatNotifier,
+		OptionsTemplate: `
+      <h3 class="page-heading">Google Hangouts Chat settings</h3>
+      <div class="gf-form max-width-30">
+        <span class="gf-form-label width-6">Url</span>
+        <input type="text" required class="gf-form-input max-width-30" ng-model="ctrl.model.settings.url" placeholder="Google Hangouts Chat incoming webhook url"></input>
+      </div>
+    `,
+	})
+}
+
+func NewGoogleChatNotifier(model *m.AlertNotification) (alerting.Notifier, error) {
+	url := model.Settings.Get("url").MustString()
+	if url == "" {
+		return nil, alerting.ValidationError{Reason: "Could not find url property in settings"}
+	}
+
+	return &GoogleChatNotifier{
+		NotifierBase: NewNotifierBase(model.Id, model.IsDefault, model.Name, model.Type, model.Settings),
+		Url:          url,
+		log:          log.New("alerting.notifier.googlechat"),
+	}, nil
+}
+
+type GoogleChatNotifier struct {
+	NotifierBase
+	Url    string
+	method string
+	log    log.Logger
+}
+
+/**
+Structs used to build a custom Google Hangouts Chat message card.
+See: https://developers.google.com/hangouts/chat/reference/message-formats/cards
+*/
+type outerStruct struct {
+	Cards []card `json:"cards"`
+}
+
+type card struct {
+	Header   header    `json:"header"`
+	Sections []section `json:"sections"`
+}
+
+type header struct {
+	Title string `json:"title"`
+}
+
+type section struct {
+	Widgets []widget `json:"widgets"`
+}
+
+// "generic" widget used to add different types of widgets (buttonWidget, textParagraphWidget, imageWidget)
+type widget interface {
+}
+
+type buttonWidget struct {
+	Buttons []button `json:"buttons"`
+}
+
+type textParagraphWidget struct {
+	Text text `json:"textParagraph"`
+}
+
+type text struct {
+	Text string `json:"text"`
+}
+
+type imageWidget struct {
+	Image image `json:"image"`
+}
+
+type image struct {
+	ImageUrl string `json:"imageUrl"`
+}
+
+type button struct {
+	TextButton textButton `json:"textButton"`
+}
+
+type textButton struct {
+	Text    string  `json:"text"`
+	OnClick onClick `json:"onClick"`
+}
+
+type onClick struct {
+	OpenLink openLink `json:"openLink"`
+}
+
+type openLink struct {
+	Url string `json:"url"`
+}
+
+func (this *GoogleChatNotifier) Notify(evalContext *alerting.EvalContext) error {
+	this.log.Info("Executing Google Chat notification")
+
+	headers := map[string]string{
+		"Content-Type": "application/json; charset=UTF-8",
+	}
+
+	ruleUrl, err := evalContext.GetRuleUrl()
+	if err != nil {
+		this.log.Error("evalContext returned an invalid rule URL")
+	}
+
+	// add a text paragraph widget for the message
+	widgets := []widget{
+		textParagraphWidget{
+			Text: text{
+				Text: evalContext.Rule.Message,
+			},
+		},
+	}
+
+	// add a text paragraph widget for the fields
+	var fields []textParagraphWidget
+	fieldLimitCount := 4
+	for index, evt := range evalContext.EvalMatches {
+		fields = append(fields,
+			textParagraphWidget{
+				Text: text{
+					Text: "<i>" + evt.Metric + ": " + fmt.Sprint(evt.Value) + "</i>",
+				},
+			},
+		)
+		if index > fieldLimitCount {
+			break
+		}
+	}
+	widgets = append(widgets, fields)
+
+	// if an image exists, add it as an image widget
+	if evalContext.ImagePublicUrl != "" {
+		widgets = append(widgets, imageWidget{
+			Image: image{
+				ImageUrl: evalContext.ImagePublicUrl,
+			},
+		})
+	} else {
+		this.log.Info("Could not retrieve a public image URL.")
+	}
+
+	// add a button widget (link to Grafana)
+	widgets = append(widgets, buttonWidget{
+		Buttons: []button{
+			{
+				TextButton: textButton{
+					Text: "OPEN IN GRAFANA",
+					OnClick: onClick{
+						OpenLink: openLink{
+							Url: ruleUrl,
+						},
+					},
+				},
+			},
+		},
+	})
+
+	// add text paragraph widget for the build version and timestamp
+	widgets = append(widgets, textParagraphWidget{
+		Text: text{
+			Text: "Grafana v" + setting.BuildVersion + " | " + (time.Now()).Format(time.RFC822),
+		},
+	})
+
+	// nest the required structs
+	res1D := &outerStruct{
+		Cards: []card{
+			{
+				Header: header{
+					Title: evalContext.GetNotificationTitle(),
+				},
+				Sections: []section{
+					{
+						Widgets: widgets,
+					},
+				},
+			},
+		},
+	}
+	body, _ := json.Marshal(res1D)
+
+	cmd := &m.SendWebhookSync{
+		Url:        this.Url,
+		HttpMethod: "POST",
+		HttpHeader: headers,
+		Body:       string(body),
+	}
+
+	if err := bus.DispatchCtx(evalContext.Ctx, cmd); err != nil {
+		this.log.Error("Failed to send Google Hangouts Chat alert", "error", err, "webhook", this.Name)
+		return err
+	}
+
+	return nil
+}

pkg/services/alerting/notifiers/googlechat_test.go

+package notifiers
+
+import (
+	"testing"
+
+	"github.com/grafana/grafana/pkg/components/simplejson"
+	m "github.com/grafana/grafana/pkg/models"
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func TestGoogleChatNotifier(t *testing.T) {
+	Convey("Google Hangouts Chat notifier tests", t, func() {
+
+		Convey("Parsing alert notification from settings", func() {
+			Convey("empty settings should return error", func() {
+				json := `{ }`
+
+				settingsJSON, _ := simplejson.NewJson([]byte(json))
+				model := &m.AlertNotification{
+					Name:     "ops",
+					Type:     "googlechat",
+					Settings: settingsJSON,
+				}
+
+				_, err := NewGoogleChatNotifier(model)
+				So(err, ShouldNotBeNil)
+			})
+
+			Convey("from settings", func() {
+				json := `
+				{
+          			"url": "http://google.com"
+				}`
+
+				settingsJSON, _ := simplejson.NewJson([]byte(json))
+				model := &m.AlertNotification{
+					Name:     "ops",
+					Type:     "googlechat",
+					Settings: settingsJSON,
+				}
+
+				not, err := NewGoogleChatNotifier(model)
+				webhookNotifier := not.(*GoogleChatNotifier)
+
+				So(err, ShouldBeNil)
+				So(webhookNotifier.Name, ShouldEqual, "ops")
+				So(webhookNotifier.Type, ShouldEqual, "googlechat")
+				So(webhookNotifier.Url, ShouldEqual, "http://google.com")
+			})
+
+		})
+	})
+}