Programmer / Developer Guide

Templating System : Developer Guide

Mini How To

Start a Tcl page as usual with ad_page_contract . Be sure to pass a -properties block; this signals the use of templating. The Tcl page should fill the data sources you promised in the contract, and not write to the connection. At the end of your Tcl page, call ad_return_template . The template system will look for an adp page with the filename stub you indicate (defaulting to the same stub as the Tcl page), process that, and deliver it to the client. The adp page can use the datasources defined in the Tcl page.


  1. User Guide
  2. Object and API Reference
  3. Template Markup Tag Reference
  4. Appendices


After the script for a page is executed, acs-templating processes the template, interpolating any data sources and executing the special tags. The resulting HTML page is written to the connection (i.e., returned to the user).
Normally, does nothing at all. With the -string option you get the resulting HTML page returned as a string.

The optional template argument is a path to a page (tcl/adp file pair). Note that you don't supply the ".tcl" or ".adp" extension. It is resolved by help of template::util::url_to_file (with the current file stub as reference path) and passed to template::set_file, to change the name of the page being served currently. If it starts with a "/", it is taken to be a path relative to the server root; otherwise it is a filename relative to the directory of the Tcl script.

Normally, complaints about incorrect parameters are written directly to the connection, and the script is aborted. With the option -return_errors you can name a variable into which to put any error messages as a list, and ad_page_contract will return in any case. You can then present the errors to the user in a templated page, consistent with the look and feel of the rest of your service. If there's no complaint, ad_page_contract won't touch the variable; typically it will stay undefined.
Christian Brechbühler
Last modified: $‌Id: developer-guide.html,v 2023/06/06 09:30:30 gustafn Exp $