Property descriptions are defined by the Common Base Event specification.
A property description describes a property that an event can contain.
This can be any property defined by the Common Base Event specification as
a simple type. A property description cannot describe a complex property such
as msgDataElement, but it can describe a simple property that is a
child of a complex property. An event definition can contain any number of
property descriptions (including none).
A property description includes the following fields:
- name
- The name of the property. This must be the name of an attribute of the
CommonBaseEvent element, or an attribute of a complex subelement of CommonBaseEvent.
Some examples are severity, priority, and globalInstanceId.
- path
- An XPath location path specifying the path to the property, if the property
is not an attribute of CommonBaseEvent. The path identifies the parent property
of the property being described. These are examples:
- To describe a property of CommonBaseEvent such as severity, do
not specify a path. A null path specifies a top-level property.
- To describe a property of msgDataElement, which is a complex property
of CommonBaseEvent, you specify the path msgDataElement.
- To describe a property of msgHelp, which is itself a complex property
of msgDataElement, specify the path msgDataElement/msgHelp.
The path can also describe a specific instance of a repeated property.
For example, if an event definition describes several contextDataElements properties,
you might specify one called businessContext, you would use the path contextDataElements[@name='businessContext'].
- defaultValue
- The default value of the property. The default value represents the value
that should be used during content completion for an event that is missing
a required property. (Therefore, it is meaningful for a property description
to be required and to define a default value.) This field is optional.
- required
- A boolean value specifying whether the property is required or optional.
If this field is equal to true, the property is required.
This field is optional; if it is not specified, the property is assumed to
be optional.
- permittedValue
- A permitted value for the property. If an event definition allows only
certain values for a property, each one is represented by a permittedValue field
in the property description. A property description can include any number
of permitted values. This field is optional and must not be specified if the minValue or maxValue fields
are specified.
- minValue
- maxValue
- The minimum and maximum permitted values for the property. If an event
definition allows a range of values for a property, these fields defines the
lower and upper bounds of that range. If you specify only minValue,
the permitted range has no upper bound; similarly, if you specify only maxValue,
the permitted range has no lower bound. These fields are optional and must
not be specified if permittedValue fields are specified.