Inspecting HTTP request parameters

An HTTP request contains a number of different parameters:

GET /search?hl=en&q=ZXTM&btnG=Google+Search HTTP/1.1
Host: www.google.com
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20041107 Firefox/1.0
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://www.google.com/
Cookie: PREF=4; recall=true; AdSenseLocale=en_US

There are a number of TrafficScript functions that make it easy to get and set each of these parameters when ZXTM is processing a request:

Inspecting the first line

$method   = http.getMethod();       # returns 'GET'
$rawurl   = http.getRawURL();       # returns '/search?hl=en&q=ZXTM&btnG=Google+Search'
$path     = http.getPath();         # returns '/search'
$querystr = http.getQueryString();  # returns 'hl=en&q=ZXTM&btnG=Google+Search'
$version  = http.getVersion();      # returns '1.1'

Inspecting headers

$host     = http.getHeader( "Host" );    # returns 'www.google.com'
$cookie   = http.getHeader( "Cookie" );  # returns 'PREF=4; recall=true; AdSenseLocale=en_US'
$adlocale = http.getCookie( "AdSenseLocale" );  # returns 'en_US'

Other functions

# An HTTP request may contain an additional POST body
$body = http.getBody();

# Iterate through a multipart POST body
$count = 0;
while( $data = http.getMultipartAttachment( $count ) ) {
   ...
   $count = $count + 1;
}

# Get a form parameter - this function inspects both the query string 
# and the POST body to look up the form parameter
$searchterm = http.getFormParam( "q" );

Most of these functions have counterparts to set the value, delete it or to test if it exists. For example:

http.setHeader( "Host", "www.zeus.com" );  # set the host header
http.removeHeader( "Accept-Encoding" );    # delete the 'Accept-Encoding' header

http.setPath( "/secure/index.html" );      # set the URL in the request
if( http.headerExists( "Cookie" ) ) ....   # did the client provide a Cookie header?

Owen Garrett [Zeus Dev Team] 01 July 2005