Configuring the Rich Text Content Policy File

The policy XML file has four notable sections:

Common Regular Expressions: In this section, the regular expressions that can be used in the rest of the policy file are defined between the <common-regexps> tags.
Common Attributes: In this section, the attributes that can be used while specifying the tag-rules are defined between the <common-attributes> tags.
Tag Rules: In this section, the parsing rules that will be used for each tag individually are defined between the <tag-rules> tags.
CSS Rules: In this section, the parsing rules that will be used for each CSS property individually are defined between the <css-rules> tags.

Once you have exported the desired policy file from the application to your local directory, you can begin making edits to the XML file.

Adding a Common Regular Expression

To create a common regular expression:

Create an alias in the Common Regular Expressions section. For example, to add the common regular expression (\d)+, make the following entry:

<common-regexps>

<regexp name=”number” value=”(\d)+”/>

</common-regexps>

Here “number” has been used as the alias for the regular expression.

Allowing a New Tag

To allow a new tag:

A new tag rule corresponding to this tag must be added in the Tag Rules section. For example, to allow the <span> tag, make the following entry:

<tag-rules>

<tag name=”span” action=”validate”/>

</tag-rules>

Here, action=”validate” ensures that the attributes of the tag follow the rules outlined for them.

Allowing a New Attribute for a Tag

To allow a new attribute for a tag:

The attribute must be added to the corresponding tag rule in the Tag Rules section. For example, to allow attribute dir for the <span> tag, make the following entry:

<tag name=”span” action=”validate”>

<attribute name=”dir”/>

</tag>

Adding a Rule for an Attribute Value

There are two ways for adding a rule for an attribute value:

Adding a list of literal values
Adding a list of regular expressions

To specify both literal values as well as regular expressions for attribute values, you can use a combination of both.

To add a list of literal values:

If you want to allow fixed values for an attribute, you need to specify a list of literal values. For example, to allow values ltr and rtl for attribute dir of the <span> tag, the following entry is made:

<tag name=”span” action=”validate”>

<attribute name=”dir” >

<literal-list>

<literal value=”ltr”/>

<literal value=”rtl”/>

</literal-list>

</attribute>

</tag>

To add a list of regular expressions:

An example of adding a list of regular expressions is to allow values that are represented by the regular expression, such as (\d)+(px) and the common regular expression number, for the attribute width of the tag <img>. To do so, the following entry is made:

<tag name=”img” action=”validate”>

<attribute name=”width” >

<regexp-list>

<regexp value=”(\d)+(px)”/>

<regexp name=”number”/>

</regexp -list>

</attribute>

</tag>

Adding Validation for Attributes

To add validation for attributes:

Certain tags and attributes can be blocked by the sanitizer by default and require validation. The following entry is an example of a change that is made in the Common Attributes section to add validation.

<regexp-list>

</regexp-list>

</attribute>

Allowing a New CSS Property

To allow a new CSS property:

A new CSS rule corresponding to this property can be added in the CSS Rules section. For example, to allow the CSS property width, the following entry is made:

<css-rules>

<property name=”width”/>

</css-rules>

Adding a Rule for a CSS Property Value

There are two ways for adding a rule for a CSS property value:

Adding a list of literal values
Adding a list of regular expressions

To specify both literal values as well as regular expressions for CSS property values, you can use a combination of both.

To add a list of literal values:

If you want to allow fixed values for a CSS property, you must specify a list of literal values. For example, to allow values auto and inherit for the CSS property width, the following entry is made:

<property name=”width”>

<literal-list>

<literal value=”auto”/>

<literal value=”inherit”/>

</literal-list>

</property>

To add a list of regular expressions:

An example of adding a list of regular expressions is to allow values that are represented by the regular expression (\d)+(px) and the common regular expression number for the CSS property width, the following entry is made:

<property name=”width”>

<regexp-list>

<regexp value=”(\d)+(px)”/>

<regexp name=”number”/>

</regexp-list>

</property>

Allowing Links in the Source Attribute of an iframe Tag

To allow links in the source attribute of an iframe tag:

Make the following entry in the XML file:

<tag name=”iframe” action=”validate”>

<attribute name=”src”>

<regexp-list>

<regexp value=”((http(s:|:))?)((//)?)((www.)?)(externaldomain/)((.)*)”/>

</regexp-list>

</attribute>

</tag>

To allow links from w3schools, for instance, simply replace externaldomain with w3schools.com.

Using a Plain Text Policy

To ensure that content of your customers, authors, and agents only use plain text, there is a simple change you can make to the policy.

To allow plain text content only:

Import a policy file with only the following content:

<?xml version=”1.0” encoding=”ISO-8859-1” ?>

<anti-samy-rules xmlns:xsi=”http://www.w3.org/2001/XMLSchema-instance”xsi:noNamespaceSchemaLocation=”antisamy.xsd”>

</anti-samy-rules>

Allowing File Protocols in the Article Content

To use file protocols in the content of a knowledge article, you can make certain changes to the policy.

To allow m-files protocol in the article content:

Make the following entries in the XML file:
- <common-regexps>
  ......
  <regexp name="mfilesURL" value="(\s)(m-files://)[\p{L}\p{N}]+[\p{L}\p{N}\p{Zs}\.\#@\$%\+&";\-_~,'\?=/!\s](\s)*"/>
  </common-regexps>
- <common-attributes>
  <attribute name="href">
  <regexp-list>
  .......
  <regexp name="mfilesURL"/>
  </regexp-list>
  </attribute>
  </common-attributes>
- <anti-samy-rules>
  ......
  <allowed-protocols value="http, https, ftp, ftps, mailto, news, file, notes, tel, sms, data, m-files"/>
  </anti-samy-rules>

Configuring the Rich Text Content Policy File

Adding a Common Regular Expression

To create a common regular expression:

Allowing a New Tag

To allow a new tag:

Allowing a New Attribute for a Tag

To allow a new attribute for a tag:

Adding a Rule for an Attribute Value

To add a list of literal values:

To add a list of regular expressions:

Adding Validation for Attributes

To add validation for attributes:

Allowing a New CSS Property

To allow a new CSS property:

Adding a Rule for a CSS Property Value

To add a list of literal values:

To add a list of regular expressions:

Allowing Links in the Source Attribute of an iframe Tag

To allow links in the source attribute of an iframe tag:

Using a Plain Text Policy

To allow plain text content only:

Allowing File Protocols in the Article Content

To allow m-files protocol in the article content:

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