alertmanager-irc-relay/format.go
Luca Bigliardi f7034fa2c2 Handle alert messages with newlines
Do not send to IRC messages with newlines, split in multiple messages
instead (see issue #15 ).

Signed-off-by: Luca Bigliardi <shammash@google.com>
2021-11-26 12:16:45 +01:00

92 lines
2.4 KiB
Go

// Copyright 2020 Google LLC
//
// 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
//
// https://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 main
import (
"bytes"
"encoding/json"
"net/url"
"strings"
"text/template"
"github.com/google/alertmanager-irc-relay/logging"
promtmpl "github.com/prometheus/alertmanager/template"
)
type Formatter struct {
MsgTemplate *template.Template
MsgOnce bool
}
func NewFormatter(config *Config) (*Formatter, error) {
funcMap := template.FuncMap{
"ToUpper": strings.ToUpper,
"ToLower": strings.ToLower,
"Join": strings.Join,
"QueryEscape": url.QueryEscape,
"PathEscape": url.PathEscape,
}
tmpl, err := template.New("msg").Funcs(funcMap).Parse(config.MsgTemplate)
if err != nil {
return nil, err
}
return &Formatter{
MsgTemplate: tmpl,
MsgOnce: config.MsgOnce,
}, nil
}
func (f *Formatter) FormatMsg(ircChannel string, data interface{}) []string {
output := bytes.Buffer{}
var msg string
if err := f.MsgTemplate.Execute(&output, data); err != nil {
msg_bytes, _ := json.Marshal(data)
msg = string(msg_bytes)
logging.Error("Could not apply msg template on alert (%s): %s",
err, msg)
logging.Warn("Sending raw alert")
alertHandlingErrors.WithLabelValues(ircChannel, "format_msg").Inc()
} else {
msg = output.String()
}
// Do not send to IRC messages with newlines, split in multiple messages instead.
newLinesSplit := func(r rune) bool {
return r == '\n' || r == '\r'
}
return strings.FieldsFunc(msg, newLinesSplit)
}
func (f *Formatter) GetMsgsFromAlertMessage(ircChannel string,
data *promtmpl.Data) []AlertMsg {
msgs := []AlertMsg{}
if f.MsgOnce {
for _, msg := range f.FormatMsg(ircChannel, data) {
msgs = append(msgs,
AlertMsg{Channel: ircChannel, Alert: msg})
}
} else {
for _, alert := range data.Alerts {
for _, msg := range f.FormatMsg(ircChannel, alert) {
msgs = append(msgs,
AlertMsg{Channel: ircChannel, Alert: msg})
}
}
}
return msgs
}