HTTP CookBook: Request and Response

HTTP Requests

All HTTP messages (requests and responses) consist of one or more headers, each on a separate line, followed by a mandatory blank line, followed by an optional message body.

GET /books/search.asp?q=wahh HTTP/1.1

Accept: image/gif, image/xxbitmap, image/jpeg, image/pjpeg, 

application/xshockwaveflash, application/vnd.msexcel, 

application/vnd.mspowerpoint, application/msword, */*

Referer: http://wahh-app.com/books/default.asp

Accept-Language: en-gb,en-us;q=0.5

Accept-Encoding: gzip, deflate

User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1)

Host: wahh-app.com

Cookie: lang=en; JSESSIONID=0000tI8rk7joMx44S2Uu85nSWc_:vsnlc502

The first line of every HTTP request consists of three items, separated by spaces:

• A verb indicating the HTTP method. The most commonly used method is GET, whose function is to retrieve a resource from the web server.
• The requested URL.
• The HTTP version being used. The only HTTP versions in common use on the Internet are 1.0 and 1.1.

HTTP Responses

A typical HTTP response is as follows:

HTTP/1.1 200 OK

Date: Sat, 19 May 2007 13:49:37 GMT

Server: IBM_HTTP_SERVER/1.3.26.2  Apache/1.3.26 (Unix)

Set-Cookie: tracking=tI8rk7joMx44S2Uu85nSWc

Pragma: no-cache

Expires: Thu, 01 Jan 1970 00:00:00 GMT

Content-Type: text/html;charset=ISO-8859-1

Content-Language: en-US

Content-Length: 24246

charset=iso-8859-1”>

...

The first line of every HTTP response consists of three items, separated by spaces:

• The HTTP version being used.
• A numeric status code indicating the result of the request.
• A textual “reason phrase” further describing the status of the response.