Header Insert of "http" or "https"

Looks good from what I can tell. The only thing I would suggest is to check for the existence of the header. This way you are not always inserting for returning connections that already have it.

 
  when HTTP_REQUEST {  
  if {([TCP::local_port] ==80) and !( [HTTP::header "X-Forwarded-Proto"] eq "http") }{  
  HTTP::header insert X-Forwarded-Proto "http"  
          log local0. "HTTP request from Client IP: [IP::client_addr] to [IP::local_addr]:[TCP::local_port]"  
         } elseif {([TCP::local_port] ==443) and !( [HTTP::header "X-Forwarded-Proto"] eq "https") } {  
          HTTP::header insert X-Forwarded-Proto "https"  
          log local0. "HTTPS request from Client IP: [IP::client_addr] to [IP::local_addr]:[TCP::local_port]"    
  }  
  }  
  

I hope this helps

Bhattman