OData Service Event Message Mapping
The OData service event type includes the child definition type Message Mapping. Service events of this type can contain one or more of these child definitions. The purpose of a message mapping is to map data in the XML document that is a part of the message received by the service event to the properties or other data values within the application.
A part of the message mapping definition is the XPath to the location of the data in the XML structure. When a data value is found it is then mapped, according to the message mapping, to either the property values of the object type targeted by the service event, or to one of a list of other options for data sources within the application.
OData Service Event Message Mapping Attributes
- Mapping Type: This attribute specifies the mapping type. This may be either XPath Expression or XML Transformation.
- Base XPath: (Optional) Use this attribute when returning multiple instances of the same data element in the XML content. When a Base XPath is defined for a response mapping, the same value is set by default in the add wizard for subsequent message mappings within the same parent service event.
- XPath: This attribute is only available when the Mapping Type is set to XPath Expression. This attribute contains the XPath value to extract the desired value from structured XML data contained in the message received by the service event.
- XSL: This attribute is only available when the Mapping Type is set to XML Transformation. It contains the XSL expression to transform the XML data contained in the message received by the service event.
- Maps To: This attribute specifies where the value extracted by the
message mapping is stored in the application. This may be one of the
following values for a service event:
- Last Update: This selection specifies the extracted value is a date and time indicating when the object’s source in the back-end system was last modified. This value is mapped to the last update value within the object instance created by the service event.
- Local String (<<local>>): This selection will create a local data tag available to subsequent message mappings in the same parent service event. The value of this data tag will be the value extracted by the response mapping. When selected, the attribute String Name will be available to name the local data tag created. This is the equivalent to calling the SDML function tag <<local ...>>.
- Local XML (<<localXML>>): This selection will create a local XML data tag available to subsequent message mappings in the same service event. The value of this data tag is the value extracted by the response mapping.
- Parent Object Key Property: This selection sets the value extracted by the message mapping to the key property of the parent object to the object created by the message received by the service event. This does not change the parent object’s key property, but rather is used by SAP Mobile Platform Server to identify which object is the parent object.
- Property Path: This selection sets the value extracted by the message mapping to the property selected in the Property Path field. This changes the value of the property to the value extracted from the message received by the service event.