alertmanager/notify/impl.go

303 lines
6.9 KiB
Go

// Copyright 2015 Prometheus Team
// 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 notify
import (
"bytes"
"crypto/tls"
"encoding/json"
"fmt"
"net"
"net/http"
"net/smtp"
"os"
"strings"
"time"
"github.com/prometheus/common/log"
"github.com/prometheus/common/model"
"golang.org/x/net/context"
"golang.org/x/net/context/ctxhttp"
"github.com/prometheus/alertmanager/config"
"github.com/prometheus/alertmanager/template"
"github.com/prometheus/alertmanager/types"
)
// Build creates a fanout notifier for each notification configuration.
func Build(confs []*config.NotificationConfig, tmpl *template.Template) map[string]Fanout {
res := map[string]Fanout{}
for _, nc := range confs {
var (
fo = Fanout{}
add = func(i int, n Notifier) { fo[fmt.Sprintf("%T/%i", n, i)] = n }
)
for i, c := range nc.WebhookConfigs {
add(i, NewWebhook(c))
}
for i, c := range nc.EmailConfigs {
add(i, NewEmail(c, tmpl))
}
res[nc.Name] = fo
}
return res
}
const contentTypeJSON = "application/json"
type Webhook struct {
URL string
}
func NewWebhook(conf *config.WebhookConfig) *Webhook {
return &Webhook{URL: conf.URL}
}
type WebhookMessage struct {
Version string `json:"version"`
Status model.AlertStatus `json:"status"`
Alerts model.Alerts `json:"alert"`
}
func (w *Webhook) Notify(ctx context.Context, alerts ...*types.Alert) error {
as := types.Alerts(alerts...)
msg := &WebhookMessage{
Version: "1",
Status: as.Status(),
Alerts: as,
}
var buf bytes.Buffer
if err := json.NewEncoder(&buf).Encode(msg); err != nil {
return err
}
resp, err := ctxhttp.Post(ctx, http.DefaultClient, w.URL, contentTypeJSON, &buf)
if err != nil {
return err
}
resp.Body.Close()
if resp.StatusCode/100 != 2 {
return fmt.Errorf("unexpected status code %v", resp.StatusCode)
}
return nil
}
type Email struct {
conf *config.EmailConfig
tmpl *template.Template
}
func NewEmail(c *config.EmailConfig, t *template.Template) *Email {
return &Email{conf: c, tmpl: t}
}
func (n *Email) auth(mechs string) (smtp.Auth, *tls.Config, error) {
username := os.Getenv("SMTP_AUTH_USERNAME")
for _, mech := range strings.Split(mechs, " ") {
switch mech {
case "CRAM-MD5":
secret := os.Getenv("SMTP_AUTH_SECRET")
if secret == "" {
continue
}
return smtp.CRAMMD5Auth(username, secret), nil, nil
case "PLAIN":
password := os.Getenv("SMTP_AUTH_PASSWORD")
if password == "" {
continue
}
identity := os.Getenv("SMTP_AUTH_IDENTITY")
// We need to know the hostname for both auth and TLS.
host, _, err := net.SplitHostPort(n.conf.Smarthost)
if err != nil {
return nil, nil, fmt.Errorf("invalid address: %s", err)
}
var (
auth = smtp.PlainAuth(identity, username, password, host)
cfg = &tls.Config{ServerName: host}
)
return auth, cfg, nil
}
}
return nil, nil, nil
}
func (n *Email) Notify(ctx context.Context, as ...*types.Alert) error {
// Connect to the SMTP smarthost.
c, err := smtp.Dial(n.conf.Smarthost)
if err != nil {
return err
}
defer c.Quit()
if ok, mech := c.Extension("AUTH"); ok {
auth, tlsConf, err := n.auth(mech)
if err != nil {
return err
}
if tlsConf != nil {
if err := c.StartTLS(tlsConf); err != nil {
return fmt.Errorf("starttls failed: %s", err)
}
}
if auth != nil {
if err := c.Auth(auth); err != nil {
return fmt.Errorf("%T failed: %s", auth, err)
}
}
}
if err := c.Mail(n.conf.Sender); err != nil {
return err
}
if err := c.Rcpt(n.conf.Email); err != nil {
return err
}
log.Debugln("sending mail", n.conf.Email, c)
// Send the email body.
wc, err := c.Data()
if err != nil {
return err
}
defer wc.Close()
data := struct {
Alerts model.Alerts
From string
To string
Date string
}{
Alerts: types.Alerts(as...),
From: n.conf.Sender,
To: n.conf.Email,
Date: time.Now().Format(time.RFC1123Z),
}
if err := n.tmpl.ExecuteText(wc, n.conf.Templates.Header, &data); err != nil {
return err
}
// TODO(fabxc): do a multipart write that considers the plain template.
return n.tmpl.ExecuteHTML(wc, n.conf.Templates.HTML, &data)
}
type Slack struct {
conf *config.SlackConfig
tmpl *template.Template
}
// slackReq is the request for sending a slack notification.
type slackReq struct {
Channel string `json:"channel,omitempty"`
Attachments []slackAttachment `json:"attachments"`
}
// slackAttachment is used to display a richly-formatted message block.
type slackAttachment struct {
Title string `json:"title,omitempty"`
TitleLink string `json:"title_link,omitempty"`
Pretext string `json:"pretext,omitempty"`
Text string `json:"text"`
Fallback string `json:"fallback"`
Color string `json:"color,omitempty"`
MrkdwnIn []string `json:"mrkdwn_in,omitempty"`
Fields []slackAttachmentField `json:"fields,omitempty"`
}
// slackAttachmentField is displayed in a table inside the message attachment.
type slackAttachmentField struct {
Title string `json:"title"`
Value string `json:"value"`
Short bool `json:"short,omitempty"`
}
func (n *Slack) Notify(ctx context.Context, as ...*types.Alert) error {
alerts := types.Alerts(as...)
var (
color = n.conf.ColorResolved
status = string(alerts.Status())
)
if alerts.HasFiring() {
color = n.conf.ColorFiring
}
var err error
tmpl := func(name string) (s string) {
if err != nil {
return
}
s, err = n.tmpl.ExecuteHTMLString(name, struct {
Alerts model.Alerts
}{
Alerts: alerts,
})
return s
}
attachment := &slackAttachment{
Title: tmpl(n.conf.Templates.Title),
TitleLink: tmpl(n.conf.Templates.TitleLink),
Pretext: tmpl(n.conf.Templates.Pretext),
Text: tmpl(n.conf.Templates.Text),
Fallback: tmpl(n.conf.Templates.Fallback),
Fields: []slackAttachmentField{{
Title: "Status",
Value: status,
Short: true,
}},
Color: color,
MrkdwnIn: []string{"fallback", "pretext"},
}
if err != nil {
return err
}
req := &slackReq{
Channel: n.conf.Channel,
Attachments: []slackAttachment{*attachment},
}
var buf bytes.Buffer
if err := json.NewEncoder(&buf).Encode(req); err != nil {
return err
}
resp, err := ctxhttp.Post(ctx, http.DefaultClient, n.conf.URL, contentTypeJSON, &buf)
if err != nil {
return err
}
// TODO(fabxc): is 2xx status code really indicator for success for Slack API?
resp.Body.Close()
if resp.StatusCode/100 != 2 {
return fmt.Errorf("unexpected status code %v", resp.StatusCode)
}
return nil
}