After the device receives the page from the server, it performs some transformations to the page template before sending it to the client. These transformations replace pre-defined HTML tag placeholders with data belonging to the client’s current session (e.g. the current resource consumption in the status page). An HTML page delivered by the server could therefore better be described as a template for an actual HTML page displayed in the client’s browser. HTML syntax was chosen for the placeholders to allow editing of page templates without interfering with syntax sensitive HTML editors.
A set of sample page templates is available from LANCOM Systems. They are not meant to be used in productive systems, but instead to illustrate the use of page templates, and provide a starting point for your own creations. In total, three placeholder tags are defined:
- <pblink identifier>text </pblink>Marks text as a clickable link to an identifier, typically to link to another page. Note that </pblink>is just an alias for </a>, since this symmetrical definition causes less trouble with HTML syntax checkers. For example, the following fragment defines a link to the help page:
Please click <pblink helplink>here</pblink>for help.
- <pbelem identifier>Insert the item specified by identifier at this place. For example, the following line inserts the user's time credit:
Session will be ended in <pbelem sesstimeout>.
- <pbcond identifier(s)>code</pbcond>Only insert code into the page if all the identifiers are TRUE, i.e. numeric values are not equal to zero and string values are not empty. Note that the current implementation does not allow nested conditionals. Continuing from the previous example, the session timeout is only displayed if there is a time limit (a session without timeout internally has a session timeout of zero):
<pbcond sesstimeout>Session will be terminated in <pbelem sesstimeout>seconds.</pbcond>