HTTP Requests
The model used for HTTP requests is to apply methods to identified resources. A HTTP request message contains a method name, a URL to which the method is to be applied, and header fields. Some requests can include a body -- for example, the data collected in a <form>-that is referred to in the HTTP standard as the entity-body.
Example B-2 shows the request message sent from a Netscape browser applying the GET method to the grapes.gif resource. The action is to retrieve the image stored in the file grapes.gif.
Example B-2. An example HTTP request message
GET /grapes.gif HTTP/1.0 Accept: image/gif, image/jpeg, image/png, */*; Accept-Charset: iso-8859-1,*,utf-8; Accept-Encoding: gzip; Accept-Language: en; Connection: Keep-Alive; Host: www.webdatabasebook.com; User-Agent = Mozilla/4.51 [en] (WinNT; I);
The first line of the message is the request-line and contains the method name GET, the request URL /grapes.gif, and the HTTP version HTTP/1.0, each separated by a space character. The request-line is followed by a list of header fields. Each field is represented as a name and value pair separated with a colon character, and lines are separated with semicolons.
The header fields are followed by a blank line and then by the optional body of the message. The POST method request usually contains a body of text, as we discuss in the next section.