ltm rule command HTTP request

iRule(1)		      BIG-IP TMSH Manual		      iRule(1)



HTTP::request
       Returns the raw HTTP request headers as a string.

SYNOPSIS
       HTTP::request

DESCRIPTION
       Returns the raw HTTP request headers as a string.

RETURN VALUE
       Returns the raw HTTP request headers as a string. You can access the
       request payload (e.g. POST data) by triggering payload collection with
       the [HTTP::collect] command and then using [HTTP::payload] in the
       [HTTP_REQUEST_DATA] event.

VALID DURING
       HTTP_REQUEST HTTP_PROXY_REQUEST

EXAMPLES
	# Note: this example would not work if the client sends a POST request with a payload, as HTTP::request does not return the payload.
	when HTTP_REQUEST {

	    # Exit this event if the request isn't a GET
	    if {[HTTP::method] ne "GET"}{return}

	    # save original request headers
	    set req [HTTP::request]

	    # flag as new request needing lookup
	    set lookup 1

	    # inject lookup URI in place of original request
	    HTTP::uri "/page.aspx?ip=[IP::client_addr]"

	    # set pool to lookup server pool
	    pool lookup_server
	    }

	    when HTTP_RESPONSE {
	    if {$lookup == 1 }{
		# collect first response (from lookup server) only
		HTTP::collect 1
	    }
	}

	when HTTP_RESPONSE_DATA {
	    # Get poolname from server response
	    # Response would ideally be in the form of a pool name only.
	    # Otherwise parse or derive the poolname here
	    set myPool [HTTP::payload]

	    # re-set flag so that subsequent response to re-tried
	    # request from real server is not processed as a lookup
	    set lookup 0

	    # verify pool exists and has members
	    if { ![catch [pool $myPool]] }{

		# Retry the request with the request headers set
		HTTP::retry $req

	    } else {

		#
		# insert dead/non-existent pool logic here
		#
	    }
	}

	And another one:
	    when HTTP_REQUEST {
		# llength uses the spaces as well as carriage returns and line feeds
		log local0. "list length: [llength [HTTP::request]], all headers: [HTTP::request]"

		# Log the request headers in hex
		binary scan [HTTP::request] H* request_hex
		log local0. "hex: $request_hex"

		# Replace the main whitespace characters with their hex equivalent (ie, " " -> \x20)
		log local0. "escaped: [string map {\x20 \\x20 \x0d \\x0d \x0a \\x0a} [HTTP::request]]"

		# Use string map to remove the \x0d carriage return
		#    then split the string on the \x0a linefeeds into a list
		set headers [split [string map {\x0d ""} [HTTP::request]] \x0a]
		set len [llength $headers]

		# Loop through each request header line and log it
		for { set i 0 } { $i <	$len } { incr i } {
		    log local0. "$i = [lindex $headers $i]"
		}
	    }

	    # /var/log/ltm output:

	    : list length: 9, all headers: GET /test.html HTTP/1.1  User-Agent: curl/7.41.0  Host: 11.3.0.10

	    : hex: 474554202f746573742e68746d6c20485454502f312e310d0a557365722d4167656e743a206375726c2f372e34312e300d0a486f73743a2031312e332e302e31300d0a4163636570743a202a2f2a0d0a0d0a

	    : escaped: GET\x20/test.html\x20HTTP/1.1\x0d\x0aUser-Agent:\x20curl/7.41.0\x0d\x0aHost:\x2011.3.0.10\x0d\x0a\x0d\x0a\x0d\x0a

	    : 0 = GET /test.html HTTP/1.1
	    : 1 = User-Agent: curl/7.41.0
	    : 2 = Host: 11.3.0.10
	    : 3 =
	    : 4 =
	    : 5 =

HINTS
SEE ALSO
CHANGE LOG
       @BIGIP-9.2.0 --First introduced the command.



BIG-IP				  2017-01-31			      iRule(1)