Chapter 5 HTTP Client Requests and Header Settings
HTTP Header Settings
•The phone processes the supported HTTP headers.
•The phone parses the XML object if ContentType is text/xml.
•The phone presents data and options to the user per the server response.
HTTP Header Settings
The following list provides definitions for HTTP header elements for
Cisco IP Phone services:
•“Refresh” (Time in Seconds, URL)
–If no time is set or it is zero, the refresh gets set to manual.
–If no URL is set, the current URL gets used.
See “HTTP Refresh Setting” for details.
•“ContentType” — The ContentType notifies the phone of the MIME type that was sent. See the “MIME Type and Other HTTP Headers” section.
•“Expires” — Expires sets the Date/Time in GMT when the page is to expire.
Pages that have expired before being loaded do not get added to the URL stack in the phone. The phone does not cache content. See “Content Expiration Header Setting” for more information.
HTTP Refresh Setting
The HTTP headers that are sent with any page from an HTTP server can include a Refresh setting. This setting comprises two parameters: a time in seconds and a URL. These two parameters direct the recipient to wait the time given in the seconds parameter and then get the data to which the URL points.
The Cisco IP Phone HTTP client properly supports this setting, which gives a great deal of power to service developers. It means that a new page can replace any XML object that displays after a fixed time.
Figure 1 shows a good example of how to use the refresh setting. This sample page shows the user the current value of Cisco stock.
1.A splash screen that displays the Yahoo logo.
| Cisco IP Phone Services Application Development Notes |