Add support for Google Chat alerts

README.md

@@ -16,7 +16,7 @@ Flagger implements several deployment strategies (Canary releases, A/B testing,
 using a service mesh (App Mesh, Istio, Linkerd)
 or an ingress controller (Contour, Gloo, NGINX, Skipper, Traefik) for traffic routing.
 For release analysis, Flagger can query Prometheus, Datadog, New Relic or CloudWatch
-and for alerting it uses Slack, MS Teams, Discord and Rocket.
+and for alerting it uses Slack, MS Teams, Discord, Rocket and Google Chat.
 
 Flagger is a [Cloud Native Computing Foundation](https://cncf.io/) project
 and part of [Flux](https://fluxcd.io) family of GitOps tools.

artifacts/flagger/crd.yaml

@@ -1191,6 +1191,7 @@ spec:
                     - msteams
                     - discord
                     - rocket
+                    - gchat
                 channel:
                   description: Alert channel for this provider
                   type: string

charts/flagger/crds/crd.yaml

@@ -1191,6 +1191,7 @@ spec:
                     - msteams
                     - discord
                     - rocket
+                    - gchat
                 channel:
                   description: Alert channel for this provider
                   type: string

go.sum

@@ -283,6 +283,7 @@ golang.org/x/crypto v0.0.0-20190611184440-5c40567a22f8/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20201002170205-7f63de1d35b0/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20210220033148-5ea612d1eb83 h1:/ZScEX8SfEmUGRHs0gxpqteO5nfNW6axyZbBdw9A12g=
 golang.org/x/crypto v0.0.0-20210220033148-5ea612d1eb83/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=

kustomize/base/flagger/crd.yaml

@@ -1191,6 +1191,7 @@ spec:
                     - msteams
                     - discord
                     - rocket
+                    - gchat
                 channel:
                   description: Alert channel for this provider
                   type: string

pkg/notifier/factory.go

@@ -52,6 +52,8 @@ func (f Factory) Notifier(provider string) (Interface, error) {
 		n, err = NewRocket(f.URL, f.ProxyURL, f.Username, f.Channel)
 	case "msteams":
 		n, err = NewMSTeams(f.URL, f.ProxyURL)
+	case "gchat":
+		n, err = NewGChat(f.URL, f.ProxyURL)
 	default:
 		err = fmt.Errorf("provider %s not supported", provider)
 	}

pkg/notifier/gchat.go

@@ -0,0 +1,120 @@
+/*
+Copyright 2020 The Flux authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package notifier
+
+import (
+	"fmt"
+	"net/url"
+)
+
+// Google Chat holds the incoming webhook URL
+type GChat struct {
+	URL      string
+	ProxyURL string
+}
+
+// GChatPayload holds the message
+type GChatPayload struct {
+	Cards []GChatCards `json:"cards"`
+}
+
+// Start - GChatCards holds the canary analysis result
+type GChatCards struct {
+	Header   GChatHeader      `json:"header"`
+	Sections []*GChatSections `json:"sections"`
+}
+
+type GChatHeader struct {
+	Title    string `json:"title"`
+	SubTitle string `json:"subtitle"`
+	ImageUrl string `json:"imageUrl"`
+}
+
+type GChatSections struct {
+	Widgets []GChatWidgets `json:"widgets"`
+}
+
+type GChatWidgets struct {
+	TextParagraph GChatText `json:"textParagraph"`
+}
+
+type GChatField struct {
+	Name  string `json:"name"`
+	Value string `json:"value"`
+}
+
+type GChatText struct {
+	Text string `json:"text"`
+}
+
+// NewGChat validates the GChat URL and returns a GChat object
+func NewGChat(hookURL string, proxyURL string) (*GChat, error) {
+	_, err := url.ParseRequestURI(hookURL)
+	if err != nil {
+		return nil, fmt.Errorf("invalid Google Chat webhook URL %s", hookURL)
+	}
+
+	return &GChat{
+		URL:      hookURL,
+		ProxyURL: proxyURL,
+	}, nil
+}
+
+// Post Google Chat message
+func (s *GChat) Post(workload string, namespace string, message string, fields []Field, severity string) error {
+	facts := make([]*GChatSections, 0, len(fields))
+	facts = append(facts, &GChatSections{
+		Widgets: []GChatWidgets{
+			{
+				TextParagraph: GChatText{
+					Text: "<font color=#848484><strong>" + message + "</strong></font>",
+				},
+			},
+		},
+	})
+	for _, f := range fields {
+		facts = append(facts, &GChatSections{
+			Widgets: []GChatWidgets{
+				{
+					TextParagraph: GChatText{
+						Text: f.Name + "<br><font color=#848484><strong>" + f.Value + "</strong></font>",
+					},
+				},
+			},
+		})
+	}
+
+	payload := GChatPayload{
+		Cards: []GChatCards{
+			{
+				Header: GChatHeader{
+					Title:    "Flagger",
+					SubTitle: fmt.Sprintf("%s.%s", workload, namespace),
+					ImageUrl: "https://flagger.app/favicon.png",
+				},
+				Sections: facts,
+			},
+		},
+	}
+
+	err := postMessage(s.URL, s.ProxyURL, payload)
+	if err != nil {
+		return fmt.Errorf("postMessage failed: %w", err)
+	}
+
+	return nil
+}

pkg/notifier/gchat_test.go

@@ -0,0 +1,53 @@
+/*
+Copyright 2020 The Flux authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package notifier
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestGChat_Post(t *testing.T) {
+
+	fields := []Field{
+		{Name: "name1", Value: "value1"},
+		{Name: "name2", Value: "value2"},
+	}
+
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		b, err := ioutil.ReadAll(r.Body)
+		require.NoError(t, err)
+
+		var payload = GChatPayload{}
+		err = json.Unmarshal(b, &payload)
+		require.NoError(t, err)
+		require.Equal(t, "podinfo.test", payload.Cards[0].Header.SubTitle)
+		require.Equal(t, len(fields), len(payload.Cards[0].Sections)-1)
+	}))
+	defer ts.Close()
+
+	GChat, err := NewGChat(ts.URL, "")
+	require.NoError(t, err)
+
+	err = GChat.Post("podinfo", "test", "test", fields, "info")
+	require.NoError(t, err)
+}