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ProxySG Content Policy Language Guide

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define active_content

Defines rules for removing or replacing active content in HTML or ASX documents. This definition 
takes effect only if it is invoked by a 

transform

 action in a 

define action

 definition block, and that 

block is in turn enabled an 

action( )

 property as a result of policy evaluation.

Active content transformation acts on the following four HTML elements in documents: 

<applet>

, 

<embed>

, 

<object>

, and 

<script>

. In addition, a script transformation removes any JavaScript 

content on the page. For each tag, the replacement can either be empty (thus deleting the tag and its 
content) or new text that replaces the tag. Multiple tags can be transformed in a single active content 
transformer. Pages served over an HTTPS tunneled connection are encrypted so the content cannot be 
modified.

Transformed content is not cached, in contrast with content that has been sent to a virus 
scanning server. Therefore, a transformer can be safely triggered based on any condition, 
including client identity and time of day.

Replaces: 

transform active_content

define active_content transformer_id 

tag_replace HTML_tag_name << text_end_delimiter

[replacement_text]

[tag_replace ...]

...

end

where:

•

—A user-defined identifier for a transformer definition block. Used to invoke the 

transformer using the 

transform

 action in a 

define action

 definition block.

•

—The name of an HTML tag to be removed or replaced, as follows:

❐

applet

—Operates on the 

<applet>

 element, which places a Java applet on a web page.

❐

embed

—Operates on the 

<embed>

 element, which embeds an object, such as a multimedia file, 

on a web page.

❐

object

—Operates on the 

<object>

 element, which places an object, such as an applet or 

media file, on a web page.

❐

script

—Operates on the 

<script>

 element, which adds a script to a web page. Also removes 

any JavaScript entities, strings, or events that may appear on the page.

If the 

tag_replace

 keyword is repeated within the body of the transformer, multiple HTML tags 

can be removed or replaced.

•

—A user-defined token that does not appear in the replacement text and 

does not use quotes or whitespace. The delimiter is defined on the first line, after the required 
double angle brackets (

<<

). All text that follows, up to the second use of the delimiter, is used as 

the replacement text.

•

—Either blank, to remove the specified tag, or new text (including HTML 

tags) to replace the tag.