Enable redirect www to non-www and vice-versa

[hgezim]

Thanks for this awesome repo.

It would be really nice if we could pass an environment variable to indicate that we want a redirect rule to happen from www.domain.example to backend domain.example or vice-versa.

[pierreozoux]

Yes, I know this part was never clear...
There was never a clear concept from our users.
If you have a good idea for that, please PR.

Maybe:

• default redirect naked domain to www
• if there is a var REDIRECT_WWW, then do the other way around.

What do you think?

(I'll not have the time to implement it)

[hgezim]

@pierreozoux,

I'll need to check if the domain listed in VIRTUAL_HOSTS is an eTLD+1 before we can start adding www to it. This go library does that: https://godoc.org/golang.org/x/net/publicsuffix

Thoughts on how I might get this into templates/haproxy.cfg.tmpl?

[pierreozoux]

nope :/

[hgezim]

Here's what I have working:

VIRTUAL_HOSTS can be set to single, command separated domains, or domains with redirection like so: "commerceowl.com=>www.commerceowl.com".

This way it's quite explicit and no magic happens. Here's the relevant code:

{{ range $host, $containers := groupByMulti $ "Env.VIRTUAL_HOST" "," }}
   {{ $redirect_parts := split $host "=>" }}
   {{ if (gt (len $redirect_parts) 1) }}
     {{ $host := index $redirect_parts 1 }}
     {{ $redirect_from := index $redirect_parts 0 }}
     redirect location https://{{ $host }} code 301 if !acme { hdr(host) -i {{ $redirect_from  }} }
     use_backend {{ $host}} if { hdr(host) -i {{ $host }} }
   {{else}}
     {{ $host := index $redirect_parts 0 }}
     use_backend {{ $host}} if { hdr(host) -i {{ $host }} }
   {{end}}
{{end}}

{{ range $host_array, $containers := groupByMulti $ "Env.VIRTUAL_HOST" "," }}
{{ range $host := split $host_array "=>" }}
backend {{ $host }}
  option http-server-close
  cookie SERVERID insert nocache indirect
  {{ range $container := $containers }}
    {{ $networkLen := len $container.Networks }}
    {{ if eq $networkLen 1 }}
      {{ $network := index $container.Networks 0 }}
  server Server {{ $network.IP }}:80 cookie Server
    {{ else }}
      {{ range $network := $container.Networks }}
        {{ if eq $network.Name "lb_web" }}
  server Server {{ $network.IP }}:80 cookie Server
        {{end}}
      {{end}}
    {{end}}
  {{end}}
{{end}}
{{end}}

I'd create a pull request but I realized I'm behind and don't understand what the REVERSE_PROXY_FOR stuff does.

[hgezim]

@pierreozoux, thoughts on the above?