Alertmanager email custom template - char '=3D' replacing

[massimogcimino]

Hi guys,

I'm tryng to use alertmanager email notification. The emails will be automatically parsed. My issue is that alertmanager emails come out translating the '=' char with a strange characters sequence: '=3D' the result is that the parsers fails.

That was verified by tcpdump betwenn alertmanager and the smarthost:

my template :
`{{ define "custom_mail_subject" }}{{ range .Alerts }}{{ index .Annotations "summary" }}{{ end }}{{ end }}
{{ define "emaildefaulthtml" }}

{{ range .Alerts }}

{{"Service= "}}{{ index .Annotations "summary" }}
{{"Host= "}}{{ index .Labels "instance" }}
{{"Address= "}}0.0.0.0
{{"Date/Time= "}}{{ .StartsAt }}
{{"AlertGroup= "}}POKER_BINGO
{{"Agent= "}}MAIL_CPN
{{"ConsoleType= "}}APP
State= {{ if eq .Status "firing" }}{{ .Labels.severity | toUpper }}{{ else }}OK{{ end }}
{{"Customer= "}}{{ index .Labels "customer" }}
{{"Additional Info= "}}{{ index .Annotations "description" | toUpper }}
{{ end }}

{{ end }}`

the tcpdump output :

`

Service=3D Host out of disk space (instance xxxxxxxx:9100)

Host=3D xxxxxxxxx

Address=3D 0.0.0.0

Date/Time=3D 2023-02-10 13:15:58.024 +0000 UTC

AlertGroup=3D POKER_BINGO

Agent=3D MAIL_CPN

ConsoleType=3D APP

State=3D CRITICAL

Customer=3D CPN

Additional Info=3D DISK IS ALMOST FULL (< 10% LEFT)\N VALUE =3D 7.20318=
4590749071\N LABELS =3D MAP[CUSTOMER:CPN DEVICE:/DEV/MAPPER/VGVAR-LVVAR FS=
TYPE:XFS HOSTNAME:RP-SASMON01 INSTANCE:RP-SASMON01:9100 JOB:MONITOR MOUNTPO=
INT:/VAR]

=20

--f28846678069f380bf3419c33a60bcd168c7e5edd6b642278fa97a500c1a--
.

K.......[4..3e.....u......
..oJ...QQUIT
`

my alertmanager configuration :

`global:
smtp_smarthost: 'xxxxxxxxx:25'
smtp_from: 'xxxxxxxxxx'
smtp_require_tls: false
route:
group_by: ['...']
group_wait: 30s
group_interval: 5m
repeat_interval: 5m
receiver: 'email_logger'
receivers:

• name: 'logger'
  webhook_configs:

  • url: 'http://xxxxxxxxxxxxxx'
    send_resolved: true

• name: 'email'
  email_configs:

  • to: 'xxxxxxxxxxxxxxxxxx'
    send_resolved: true

• name: 'email_logger'
  email_configs:

  • to: 'xxxxxxxxxxxxxx'
    headers:
    subject: '{{ template "custom_mail_subject" . }}'

    html: '{{ template "emaildefaulthtml" . }}'
    send_resolved: true
    webhook_configs:

  • url: 'http://xxxxxxxxx'
    send_resolved: true
    templates:

• '/etc/alertmanager/templates/mail.tmpl'

• '/etc/alertmanager/templates/text.tmpl'`

any suggestion to fix?