How to Read Configuration Schema

Configuration schema file for IIS settings: %windir%\system32\inetsrv\config\schema\IIS_Schema.xml.

The schema for each configuration section is defined in an XML element. There is no schema definition for section groups. The following format is used here to explain how to read the schema:

<attribute-name>="<default-value>" [<metadata>] [<description>]

<attribute-name> is the name of the configuration attribute, as it appears in XML. Every attribute must have a name.

<default-value> is the value used by default, if no other value is specified in the XML for the attribute. Not all attributes have default values (for example, site name). In this case, the syntax will be "".

<metadata> contains several items:

• The runtime type of the attribute. This is one of "bool", "enum", "flags", "int", "int64", "String", "timeSpan". Every attribute must have a type.
• "bool" is "true" or "false".
• "enum" is a set of possible values, where only one of them can be set for the attribute. Every such value has a numerical value and a friendly name. The syntax is using the character "|" as a delimiter between the friendly names: value1|value2|…|valueN.
• "flags" is similar to "enum", except that combinations of values are allowed. Therefore the numerical values should be in multiples of 2, so they can be ORed together to form combinations. The syntax is identical to "enum": value1|value2|…|valueN.
• "int" is a 32 bit integer.
• "int64" is a 64 bit integer.
• "String" is a character string.
• "timeSpan" is a representation of a time unit, similar to the managed-code type TimeSpan. It can be persisted as a number (representing seconds, or minutes); or as a formatted string in the form of "[dd:]hh:mm:ss". The "[dd:]" element represents an optional number of days. The other elements represent numbers of hours, minutes and seconds, respectively. The "timeSpanFormat" attribute specifies which format should be used: number of seconds, number of minutes, or a formatted string.
• Required attributes are marked "Required". It means that a value for them must be set in the XML. For example, site name is a required attribute (every site must have a name in IIS 7.0).

<description> is a short description of the attribute.

Section Schema

The <sectionSchema> XML element is the base unit of schema information. All other schema information is specified within it. It has one attribute directly in it ("name"), and then the rest of the schema is in sub-elements within it.

Attribute Schema

Every attribute is defined in a corresponding <attribute> XML element in the schema. The <attribute> element may be in the <sectionSchema> element directly (if the attribute is in the section scope); or in the element (if the attribute is in a sub-element within the section); or in the <collection> element (if the attribute is in a collection within the section).
An attribute schema must specify a name and a runtime type for the attribute. It may mark the attribute as required. It may mark the attribute as the unique key (if inside a collection), or as part of a collection key (together with other attributes). It may specify a default value for the attribute. It may mark the attribute for automatic encryption on-disk. It may specify if the word "Infinite" is allowed as a value for the attribute (only for numeric types such as int and in64, and for timeSpan). It may specify the timespan format (seconds, minutes or formatted string) for timespan attributes. It may specify validation rules for the attributes (see Attribute Validation section below in this document).

 <ATTRIBUTE
    name=""  [String, Required] [XML name of the attribute]    type=""  [bool|enum|flags|int|int64|string|timeSpan, Required][Runtime type]
    required="false"  [bool] [Indicates if must be set]
    isUniqueKey="false"    [bool] [Serves as the collection key]
    isCombinedKey="false"  [bool] [Part of a multi-attribute key]
    defaultValue=""  [String] [Default value or comma-delimited flags]
    encrypted="false"  [bool] [Indicates if value persisted is encrypted] 
    allowInfinite="false"  [bool] [Indicates if "Infinite" can be set]
    timeSpanFormat="string" [string|seconds|minutes] [hh:mm:ss or number]
    validationType=""       [See validation below]
    validationParameter=""  [See validation below]

/>