traefik compatibility

[franklaich]

hi,

I wanted to switch from nginx to traefik as proxy to forward to clammit.
therefor i was looking how to set the X-Clammit-Backend with the given traefik possibilities.

I did not find any solution suitable for my needs.

my solution now is to patch your forwarder.go:

func (f *Forwarder) getApplicationURL(req *http.Request) *url.URL {
		 // Return the applicationURL if it's set
		 if f.applicationURL != nil && f.applicationURL.String() != "" {
				 return f.applicationURL
		 }
 
		 // Otherwise check for the X-Clammit-Backend header
		 url, err := url.Parse(req.Header.Get(applicationUrlHeader))
		 if err != nil {
				 f.logger.Panicf("Error parsing application URL in %s: %s (%s)", applicationUrlHeader, err.Error(), req.Header.Get(applicationUrlHeader))
				 return nil
		 }
 
		 if len(url.String()) == 0 {
				 **f.logger.Print("No application URL available - header %s is blank", applicationUrlHeader)
				 // patch by Top21
				 f.logger.Print("Try to build from X-Forwarded-")
				 url,err = url.Parse(req.Header.Get("X-Forwarded-Proto") + "://" + req.Header.Get("X-Forwarded-Host"))**
		 }
 
		 return url
 }

maybe this is helpful for others too and you can implement it somehow in the main code.

cheers,

frank