The most basic properties file consists of a single Component element with attributes, a single nested PropertyDescriptors element, and a single nested Views element. In the example properties file depicted above, the PropertyDescriptors and Views elements are empty. As the discussion progresses, the PropertyDescriptors element is populated with a variety of Property elements and Control elements; the Views element is populated with a variety of View elements, Group elements, and PropertyRef elements. Some of these elements are used to integrate the node into the SAS Enterprise Miner application. Some elements link the node with a SAS program that you write to provide the node with computational functionality. Other elements are used to populate the node's Properties panel, which serves as a graphical user interface (GUI) for the node's SAS program.

The Component Element

The Component element encompasses all other elements in the properties file. The attributes of the Component element provide information that is used to integrate the extension node into the SAS Enterprise Miner environment. All extension nodes share three common Component attributes: type, resource, and serverclass. These three attributes must have the values that are displayed in the preceding example. The values of the other Component attributes are unique for each extension node.

These other Component attributes convey the following information:

name — the name of the node as it appears on the node's icon in a process flow diagram.
displayName — the name of the node that is displayed in the tooltip for the node's icon on the node Toolbar and in the tooltip for the node's icon in a process flow diagram. The amount of text that can be displayed on an icon is limited but tooltips can accommodate longer strings.
description — a short description of the node that appears as a tooltip for the node Toolbar.
group — the SEMMA group where the node appears on the SAS Enterprise Miner node Toolbar. The existing SEMMA group values are as follows:
- Sample
- Explore
- Modify
- Model
- Assess
- Utility
If you select a value from this list, your extension node's icon appears on the toolbar under that group. However, you can add your own group to the SEMMA toolbar by specifying a value that is not in this list.
icon — the name of the two GIF files that are used to generate the SAS Enterprise Miner icons. The two GIF files share a common filename.
prefix — a string used to name files (data sets, catalog, and so on) that are created on the server. The prefix must be a valid SAS variable name and should be as short as possible. SAS filenames are limited to 32 characters, so if your prefix is k characters long, SAS Enterprise Miner is left with 32 – k characters with which to name files. The shorter the prefix, the greater the flexibility the application has for generating unique filenames.

Consider the following example:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE Component PUBLIC
		"-//SAS//EnterpriseMiner DTD Components 1.3//EN"
		"Components.dtd">
<Component
	type="AF"
	resource="com.sas.analytics.eminer.visuals.PropertyBundle"
	serverclass="EM6"
	name="Example"
	displayName="Example"
	description="Extension Node Example"
	group="EXPLORE"
	icon="Example.gif"
	prefix="EXMPL" >

<PropertyDescriptors>
</PropertyDescriptors>

<Views>
</Views>

</Component>

The displayName="Example" and

description="Extension
                     Node Example"

attributes together produce the tooltip that appears when you position your mouse pointer over the extension node's icon on the node Toolbar.

The name="Example" attribute produces the name on the icon in the following example. The displayName="Example" produces the tooltip that is displayed when you position your mouse pointer over the node's icon in the process flow diagram.

The group="EXPLORE" attribute informs SAS Enterprise Miner that the extension node's icon should be displayed in the Explore tab of the node toolbar. The icon="Example.gif" attribute informs SAS Enterprise Miner of the name of the GIF file used to produce the icon on the node toolbar. The prefix="EXMPL" attribute informs SAS Enterprise Miner that filenames of files generated on behalf of this node should share a common prefix of EXMPL. The prefix is also used as the Node ID in the Properties panel. When deployed, this extension node would have the following Properties panel:

The General properties and Status properties that are displayed here are common to all nodes and are generated automatically by SAS Enterprise Miner.

The PropertyDescriptors Element

General Information

The PropertyDescriptors element provides structure to the XML document. Having all of the Property elements encompassed by a single PropertyDescriptors element isolates the Property elements from the rest of the file's contents and promotes efficient parsing. The real information content of the PropertyDescriptors element is provided by the individual Property elements that you place within the PropertyDescriptors element. A variety of Property elements can be used in an extension node. Each type of Property element is discussed in detail here. Working examples for each type of Property element are also provided.

In the following sections, you will see example code that creates four different property types. Those types are string, Boolean, integer, and double. The extension node’s Properties Panel will resemble the following image:

Properties Panel with no control elements

These four elements are the most basic forms of the available Property elements. For some applications, the basic forms are sufficient. However, some applications might require a more sophisticated interface. You might also want to restrict the set of valid values that a user can enter. Such capabilities are provided by Control elements.

Note: For this example, all of the newly created properties were placed under the heading Train. That heading was generated using a View element, discussed later.

Property Elements

The different types of Property elements are distinguished by their attributes. The attributes that are currently supported for extension nodes are as follows:

type — specifies one of four supported types of Property element. The supported types are String, boolean, int, and double. These values are case sensitive.
name — a name by which the Property element is referenced elsewhere in the properties file and in the node's SAS code. At run time, SAS Enterprise Miner generates a corresponding macro variable with the name &EM_PROPERTY_name. By default, &EM_PROPERTY_name resolves to the value that is declared in the initial attribute of the Property element. If a user specifies a value for the property in the Properties panel, &EM_PROPERTY_name resolves to that new value. Macro variable names are limited to 32 characters. Twelve characters are reserved for the EM_PROPERTY_ prefix, so the value specified for the name attribute must be 20 characters or less.
displayName — the name of the Property element that is displayed in the node's Properties panel.
description — the description of the Property element that is displayed in the node's Properties panel.
initial — defines the initial or default value for the property.
edit — indicates whether the user can modify the property's value. Valid values are Y and N.

Some Property elements support all of these attributes, and some support only a subset.

Examples of the syntax for each of the four type attributes are provided below. These examples can be copied and used to create your own properties file. All you need to do is change the values for the name, displayName, description, initial, and edit attributes.

The String Property

<Property
	type="String"
	name="StringExample"
	displayName="String Property Example"
	description="write your own description here"
	initial="Initial Value"
	edit="Y" />

The value of a String property is displayed as a text box that a user can edit. Use a String property when you want the user to enter a string value. For example, your extension node might create a new variable, and you could allow the user to provide a variable label.

The preceding example is typical of a String Property element that corresponds to a specific option or argument of the node's SAS program. However, there are two special String Property elements, referred to as the Location Property and the Catalog Property, that you must include in the properties file. These two special String Property elements are used to inform SAS Enterprise Miner of the location of the node's SAS program. These two Property elements appear as follows:

<Property
	type="String"
	name="Location"
	initial="CATALOG"/>

<Property
	type="String"
	name="Catalog"
	initial="SASHELP.EMEXT.Example.SOURCE"/>

The

Location
                        Property

should be copied verbatim. The

Catalog
                        Property

can also be copied. However, you should change the value of the initial attribute to the name of the file that contains the entry point of your SAS program in the Catalog Property. As discussed earlier in the section on Server Code, your SAS program can be stored in several separate files. However, there must always be one file that contains a main program that executes first. The value of the initial attribute of the Catalog Property should be set to the name of this file. If you want to store the main program in an external file, you still need to create a source file that is stored in a SAS catalog. The contents of that file would then simply have the following form:

filename temp 'filename';
%include temp;
filename temp;

Here, filename is the name of the external file that contains the main program.

The Boolean Property

<Property
	type="boolean"
	name="BooleanExample"
	displayName="Boolean Property Example"
	description="write your own description here"
	initial="Y" />

The

Boolean
                        Property

is displayed as a drop-down list; the user can select either Yes or No.

The Integer Property

<Property
	type="int"
	name="Integer"
	displayName="Integer Property Example"
	description="write your own description here"
	initial="20"
	edit="Y">
</Property>

The value of an

Integer
                        Property

is displayed as a text box that a user can edit. Use an Integer Property when you want the user to provide an integer value as an argument to your extension node's SAS program.

The Double Property

<Property
	type="double"
	name="Double"
	displayName="Double Property Example"
	description="write your own description here"
	initial="0.02"
	edit="Y">
</Property>

The value of a

Double
                        Property

is displayed as a text box that a user can edit. Use a Double Property when you want the user to provide a real number as an argument to your extension node's SAS program.

The Control Element

General Information

In addition to specifying the attributes for a Property element, you can also specify one of several types of Control elements. Control elements are nested within Property elements. Each type of Control element has its own unique syntax.

Some common Control elements include the following:

ChoiceList — displays a predetermined list of values.
Range — validates a numeric value entered by the user.
SASTABLE — opens a Select a SAS Table window that enables the user to select a SAS data set.
FileTransfer — provides a dialog box that enables a user to select a registered model.
Dialog — opens a dialog box that provides access to a variables table from a predecessor data source node, an external text file, or a SAS data set.
TableEditor — displays a table and permits the user to edit the columns of the table.
DynamicChoiceList — displays a dynamically generated list of values. This type of Control element is used with a TableEditor Control element.
DirectorySelector — opens a Select Server Directory window that enables the user to select a directory.

Some Control elements require accompanying server code to provide functionality. These include the TableEditor, DynamicChoiceList, Filetransfer, and some Dialog Control elements. See Controls that Require Server Code for examples of these types of Control element. This chapter follows a discussion of extension node server code.

Examples of the syntax for certain Control elements that do not require server code follow. These examples can be copied and used to create your own properties file.

This document does not cover all of the Control elements that are available for extension nodes. See the Ext Demo node and its documentation for examples of other Control elements.

String Property with a ChoiceList Control

<Property
	type="String"
	name="ChoiceListExample"
	displayName="Choice List Control Example"
	description="write your own description here"
	initial="SEGMENT">
	<Control>
		<ChoiceList>
		<Choice rawValue="SEGMENT" displayValue="Segment" />
		<Choice rawValue="ID" displayValue="ID" />
		<Choice rawValue="INPUT" displayValue="Input" />
		<Choice rawValue="TARGET" displayValue="Target" />
		</ChoiceList>
	</Control>
</Property>

A ChoiceList control enables you to present the user with a drop-down list that contains predetermined values for a property. A String property with a ChoiceList control consists of the following items:

a Property element with attributes.
a single Control element.
a single ChoiceList element.
two or more Choice elements. Each Choice element represents one valid value for a program option or argument.

Each Choice element has the following attributes:

rawValue — the value that is passed to the node's SAS program.
displayValue — the value that is displayed to the user in the Properties panel. It can be any character string. If no displayValue is provided, the rawValue is displayed.

Note: Make sure that the value of the initial attribute of the Property element matches the rawValue attribute of one of the Choice elements. The value of the Property element's initial attribute is the default value for the property; it is the value that is passed to your SAS program if the user does not select a value from the Properties panel. If the initial attribute does not match the rawValue attribute of one of the Choice elements, you could potentially be passing an invalid value to your SAS program. To avoid case mismatches, it is a good practice to write the rawValue attributes and the initial attribute using all capital letters.

String Property with a Dialog Control

There are three types of Dialog Control elements supported for extension nodes in SAS Enterprise Miner. The Dialog elements are uniquely distinguished by their class attributes. The class attributes are as follows:

com.sas.analytics.eminer.visuals.VariablesDialog
com.sas.analytics.eminer.visuals.CodeNodeScoreCodeEditor
com.sas.analytics.eminer.visuals.InteractionsEditorDialog

In each of the three cases, the class attribute must be specified verbatim. The Dialog control with class=com.sas. analytics.eminer.visuals.VariablesDialog is the only Dialog control of the three that does not require accompanying server code.

Dialog Control with class=com.sas.analytics.eminer.visuals.VariablesDialog

<Property
	type="String"
	name="VariableSet"
	displayName="Variables"
	description="Variable Properties">
	<Control>
		<Dialog
			class="com.sas.analytics.eminer.visuals.VariablesDialog"
			showValue="N" />
	</Control>
</Property>

This Property element configuration provides access to the variables exported by a predecessor Data Source node. Notice the class attribute of the Dialog element. When you include a Property element of this type, the displayName value is displayed in the Properties panel and an ellipsis icon ( ellipses button

) is displayed in the Value column.

Clicking on the ellipses icon

icon opens a window containing a variables table. A filter based on the variable metadata column values can be applied so that only a subset of the variables is displayed in the table. The user can set the Use and Report status for individual variables, view the columns metadata, or open the Explore window. In the Explore window, the user can view a variable's sampling information, observation values, or plots of variables' distributions.

If you set the value of the showValue attribute to Y, the name of the VariableSet data set name is displayed beside the ellipsis icon.

Note: You use this Property and Control configuration only when you want the user to be able to control which variables the node uses.

The other two types of Dialog Control elements are used to access files or data sets that are not exported by predecessor nodes in a process flow diagram. In order to access such files or data sets, you must first register these files or data sets with Enterprise Miner. This topic is explained later in a discussion about extension node server code. Therefore, illustrations of the two additional

Dialog
                        Control

elements are presented in a later chapter after you have gained the requisite knowledge for registering files and data sets that are to be accessed by your extension node.

Integer Property with a Range Control

<Property
	type="int"
	name="Range"
	displayName="Integer Property with Range Control"
	description="write your own description here"
	initial="20"
	edit="Y">
	<Control>
		<Range min="1"
			excludeMin="N"
			max="1000"
			excludeMax="N"/>
	</Control>
</Property>

The addition of the

Range
                        Control

element to an Integer Property element enables you to restrict the range of permissible values that a user can enter. The Control element has no attributes in this case. Instead, a Range element is nested within the Control element. The Range element has these four attributes:

min — an integer that represents the minimum of the range of permissible values.
excludeMin — when this attribute is set to Y, the minimum value of the range that is declared in the min attribute is excluded as a permissible value. When this attribute is set to N, the minimum value is a permitted value.
max — an integer that represents the maximum of the range of permissible values.
excludeMax — when this attribute is set to Y, the maximum value of the range that is declared in the max attribute is excluded as a permissible value. When this attribute is set to N, the maximum value is a permitted value.

If the user enters a value that is outside the permissible range, the value reverts to the previous valid value.

Double Property with a Range Control

<Property
	type="double"
	name="double_range"
	displayName="Double Property with Range Control"
	description="write your own description here"
	initial="0.33"
	edit="Y">
	<Control>
		<Range
			min="0"
			excludeMin="Y"
			max="1"
			excludeMax="Y" />
	</Control>
</Property>

The addition of the

Range
                        Control

element to a Double Property element enables you to restrict the range of permissible values that a user can enter. The Control element has no attributes in this case. Instead, a Range element is nested within the Control element. The Range element has these four attributes:

min — an integer that represents the minimum of the range of permissible values.
excludeMin — when this attribute is set to Y, the minimum value of the range that is declared in the min attribute is excluded as a permissible value. When this attribute is set to N, the minimum value is a permitted value.
max — an integer that represents the maximum of the range of permissible values.
excludeMax — when this attribute is set to Y, the maximum value of the range that is declared in the max attribute is excluded as a permissible value. When this attribute is set to N, the maximum value is a permitted value.

If the user enters a value that is outside the permissible range, the value reverts to the previous valid value.

String Property with a SASTABLE Control

<Property
	type="String"
	name="SASTable"
	displayName="SASTABLE Control Example"
	description="write your own description here"
	initial=""
	edit="Y">
	<Control
		type="SASTABLE"
		showValue="Y"
		showSystemLibraries="Y"
		noDataSpecified="Y" />
</Property>

SASTABLE
                        Control

element enables the user to select the name of a SAS data set. The default value of a String Property element with a SASTABLE control is a null string.

When the user clicks on the ellipses icon

icon, a Select a SAS Table window is displayed and the user is permitted to select a SAS data set from the SAS libraries that are displayed.

The Control element has these four attributes:

type — declares the type of control. This attribute value must be set to SASTABLE to produce the effect depicted here.
showValue — when set to Y, this attribute displays the name of the data set selected by the user in the Value column of the Properties panel. When this attribute is set to N, the Value column of the Properties panel remains empty even when a user has selected a data set.
showSystemLibraries — when this attribute is set to Y, SAS Enterprise Miner project libraries are displayed in the Select a SAS Table window. When this attribute is set to N, SAS Enterprise Miner project libraries are not displayed in the Select a SAS Table window. For example, in the previous example, notice the SAS Enterprise Miner project libraries Emds, Emlds, Emlmeta, Emmeta, and Emws2. If the showSystemLibraries attribute had been set to N, these SAS Enterprise Miner libraries would not be displayed.
noDataSpecified — When this attribute is set to Y, a check box with the label No data set to be specified appears in the bottom left corner of the Select a SAS Table window. When checked, the SASTABLE control is cleared and the value of the String Property is set to null. When set to N, this attribute has no effect.

The default values of the property and the corresponding macro variable &EM_PROPERTY_propertyname are null. When a user selects a data set, the name of the data set is assigned to &EM_PROPERTY_propertyname and is displayed in the Value column of the Properties panel. The property's value can be changed to another data set name by clicking on the icon and selecting a new data set. Clicking on the ellipses icon

icon and then clicking on the No data set to be specified check box clears the property.

String Property with a TableEditor Control: A Preview

String
                        Property

with a TableEditor control requires SAS code in order for it to function properly. Because this control requires server code, which has not yet been discussed, a complete discussion and example of this type of Property and Control configuration is provided in Appendix 2: Controls that Require Server Code. This section provides a preview of the most basic type of table editor. This preview also serves as a reference example for the discussion on server code in the next chapter.

When a

String
                        Property

with a TableEditor control is implemented, an ellipsis icon ( ellipses icon

) appears in the Value column of the Properties panel next to the property name.

Clicking on the icon opens a Table Editor window, which displays a table that is associated with the Control element.

Depending on how the Control element is configured, a user might then edit some or all of the values in the table. You also have the option of writing specially identified blocks of SAS code that execute either when the table first opens or when the table is closed.

String Property with a DirectorySelector

<Property
	type="String"
	name="DirectorySelector"
	displayName="Directory Selector"
	description="Dialog to select a directory"
	edit="Y">

	<Control>
      <Custom class="com.sas.analytics.eminer.
      visuals.DirectoryBrowswer">
         <Option name="allowTyping" value="Y" />
      </Custom>
   </Control>
</Property>

A DirectorySelector control enables you to present the user with a Selector Server Directory dialog box. This is useful if your node needs to save several files to or import several files from the same directory.

The Views Element

General Information

The Views element organizes properties in the Properties panel. The following Properties panel contains one of each type of Property element:

Here is the Views element of the XML properties file that generates this Properties panel:

<Views>
	<View name="Train">
		<PropertyRef nameref="StringExample"/>
		<PropertyRef nameref="BooleanExample"/>
		<PropertyRef nameref="Integer"/>
		<PropertyRef nameref="Double"/>
		<PropertyRef nameref="ChoiceListExample"/>
		<PropertyRef nameref="VariableSet"/>
		<PropertyRef nameref="Range"/>
		<PropertyRef nameref="double_range"/>
		<PropertyRef nameref="SASTable"/>
	</View>
</Views>

Within the Views element, there is a single View element. That View element has a single attribute — name — and its value is Train. Nested within the View element is a collection of PropertyRef elements. There is one PropertyRef element for each Property element in the properties file. Each PropertyRef element has a single nameref attribute. Each nameref has a value that corresponds to the name attribute of one of the Property elements.

When you add the

Train
                        View

element, SAS Enterprise Miner separates the node's properties into three groups: General, Train, and Status. The General and Status groups are automatically generated and populated by SAS Enterprise Miner. These two groups and the properties that populate them are common to all nodes and do not have to be specified in the extension node's XML properties file. The Train group contains all of the properties that are specified by the PropertyRef elements that are nested within the Train View element.

Now suppose that instead of a single View element, there were three View elements: Train, Score, and Report. Suppose that we also remove some of the PropertyRef elements from the Train View, put some in the

Score
                        View

, and put the rest in the Report View, as follows:

<Views>
	<View name="Train">
		<PropertyRef nameref="StringExample"/>
		<PropertyRef nameref="BooleanExample"/>
		<PropertyRef nameref="Integer"/>
		<PropertyRef nameref="Double"/>
	</View>
	<View name="Score">
		<PropertyRef nameref="ChoiceListExample"/>
		<PropertyRef nameref="VariableSet"/>
		<PropertyRef nameref="SASTable"/>
	</View>
	<View name="Report">
		<PropertyRef nameref="Range"/>
		<PropertyRef nameref="double_range"/>
	</View>
</Views>

The following Properties panel would appear as a result:

By convention, SAS Enterprise Miner nodes use only three View elements with the names Train, Score, and Report. However, not all nodes need all three View elements. Although it is recommended, you are not required to follow this convention. Your node can have as many different View elements as you like and you can use any names that you want for the View elements.

The Group Element

You can indicate to the user when a set of Property elements is related by placing the related Property elements in a group. When a group is defined, all of the properties in the group appear as items in an expandable and collapsible list under a separate subheading. This is accomplished by nesting a Group element within a View element and then nesting PropertyRef elements inside the Group element.

Group elements have three attributes.

name — uniquely identifies the Group to the Enterprise Miner server.
displayName — the name of the Group that is displayed in the node's Properties panel.
description — the description of the Group that is displayed in the node's Properties panel.

For example, consider the following Views configuration:

<Views>
	<View name="Train">
		<PropertyRef nameref="StringExample" />
		<PropertyRef nameref="BooleanExample" />
		<Group
			name="GroupExample"
			displayName="Group Example"
			description="write your own description here">
			<PropertyRef nameref="Integer" />
			<PropertyRef nameref="Double" />
			<PropertyRef nameref="ChoiceListExample" />
		</Group>
		<PropertyRef nameref="VariableSet" />
		<PropertyRef nameref="SASTable" />
		<PropertyRef nameref="Range" />
		<PropertyRef nameref="double_range" />
	</View>
</Views>

The following Properties panel results:

You can click on the + or - sign beside the group name to expand or collapse, respectively, the list of properties that are included in a group.

You can examine the XML properties files of existing SAS Enterprise Miner nodes and use them as guides to constructing your own properties files. The exact location of these files depends on your operating system and installation configuration, but they can be found under the SAS configuration directory: ...\SAS\Config\Lev1\AnalyticsPlatform\apps\EnterpriseMiner\conf\components.

Be aware, however, that SAS Enterprise Miner nodes can have features that are not supported for extension nodes. If you see an attribute in a SAS node's XML properties file that is not documented here, assume that the attribute is not supported for extension nodes.

The SubGroup Element

You might also encounter situations where your node's SAS program has many options and arguments. In such cases, the list of properties can become too long to conveniently display in the Properties panel. In such situations, you might want to have related properties in their own separate Properties panel. This is accomplished by using SubGroup elements. SubGroup elements have essentially the same structure as Group elements. That is, SubGroup elements have these three attributes:

name — uniquely identifies the SubGroup to the Enterprise Miner server.
displayName — the name of the SubGroup that is displayed in the node's Properties panel.
description — the description of the SubGroup that is displayed in the node's Properties panel.

Nest the SubGroup element within a View element, and nest PropertyRef elements within the SubGroup element. When a SubGroup element is used, an ellipses icon

icon appears in the Value column of the Properties panel next to the displayName of the SubGroup. Clicking the ellipses icon

icon opens a child window. The properties that are nested within the SubGroup element are displayed in that window. The Property elements and Control elements within the subgroup's Properties panel function the same way they function in the main Properties panel.

For example, consider the following Views element:

<Views>
	<View name="Train">
		<SubGroup
			name="SubGroupExample"
			displayName="SubGroup Example"
			description="write your own description here">
			<PropertyRef nameref="BooleanExample"/>
			<PropertyRef nameref="StringExample"/>
			<PropertyRef nameref="Integer"/>
			<PropertyRef nameref="Double"/>
		</SubGroup>
		<PropertyRef nameref="ChoiceListExample"/>
		<PropertyRef nameref="VariableSet"/>
		<PropertyRef nameref="SASTable"/>
		<PropertyRef nameref="Range"/>
		<PropertyRef nameref="double_range"/>
	</View>
</Views>

The following Properties panel results:

The four properties that are nested in the SubGroup element do not appear in the Properties panel. Instead, the SubGroup element's name value is displayed. Clicking the adjacent ellipses icon

icon opens the following child window: