Bug: When I'm using docker-compose, After I put smtp service under the traefik, and I'm using the proxyProtocol, The connection will breke

[yingshaoxo]

Here is the traefik code:

tcp:
  routers:
    smtp_router:
      entryPoints:
        - smtp
      rule: "HostSNI(`*`)"
      service: smtp_service
  services:
    smtp_service:
      loadBalancer:
        servers:
          - address: weloveparty_account_auth_service:25
        proxyProtocol:
          version: 2
        terminationDelay: 200

https://traefik.io/blog/announcing-traefik-2-4/#:~:text=However%2C%20when%20forwarding-,SMTP%20connections,-to%20a%20service

[yingshaoxo]

The error is:

root@my-new-vps:~/we_love_party/email_platform# python3 email_send.py 
Traceback (most recent call last):
  File "/root/we_love_party/email_platform/email_send.py", line 12, in <module>
    s.send_message(msg)
  File "/usr/lib/python3.10/smtplib.py", line 943, in send_message
    self.ehlo_or_helo_if_needed()
  File "/usr/lib/python3.10/smtplib.py", line 614, in ehlo_or_helo_if_needed
    raise SMTPHeloError(code, resp)
smtplib.SMTPHeloError: (500, b'Error: bad syntax')

and

party_protocols-weloveparty_account_auth_service-1  | ('172.18.0.11', 35778) unrecognised: 

[waynew]

I don't think this is an aiosmtpd issue - it looks like traefik is terminating, possibly lines incorrectly.

I had a similar issue - Exchange was strict about the \r\n and my custom handler was joining with \n