18
Connection Set Specification
About the Connection Set Grammar
In XFA terminology a
connection
is a link between a subset of the data in the Form DOM and some external
entity. An XDP can potentially have many data descriptions and potentially many connections for each
data description.
The set of connections is contained within the XDP inside a
connectionSet
packet. There can be at most
one
connectionSet
packet per XDP. Within the
connectionSet
packet there can be any number of
wsdlConnection
elements, but at most one element that is either an
xmlConnection
or an
xsdConnection
. The order of multiple
wsdlConnection
elements is not significant, but they must
each have a unique name attribute.
An
xmlConnection
element associates a data description with sample XML data. An
xsdConnection
element associates a data description with an external schema in [XMLSchema] format. Both
xmlConnection
and
xsdConnection
are used for data which is to be exported as and/or imported
from a standalone XML document. By contrast a
wsdlConnection
element describes how the form
interacts with a WSDL-based service using SOAP doc-literal operations.
Any subform, field, or exclusion group in the Form DOM can be associated with a connection by a connect
element. This causes the content of the subform, field, or exclusion group to be included in the data
transferred by that connection. A given subform, field, or exclusion group can be associated with any
number of different connections.
An event element in the template controls the invocation of a connection. This element can only be used
with a connection defined by a
wsdlConnection
element. Invoking the connection causes the web
service to be invoked using the sequence of operations listed under
“Using Web Services” on page 329.
The following skeleton summarizes the structure of the connection set element and its descendants:
<connectionSet
xmlns="http://www.xfa.org/schema/xfa-connection-set/2.4/">
<!--
zero or more of...-->
<wsdlConnection dataDescription="ddName" name="cxnName">
<operation input="inputElementName"
output="outputElementName"
>wsdlOperationName</operation>
<soapAction>actionURI</soapAction>
<soapAddress>endpointURI</soapAddress>
<wsdlAddress>wsdlURI</wsdlAddress>
</wsdlConnection>
<!--
at most one of eitherthis... -->
<xmlConnection dataDescription="ddName" name="cxnName">
<uri>sampleDataURI</uri>
</xmlConnection>
<!--
...or this... -->
<xsdConnection dataDescription="ddName" name="cxnName">
<rootElement>elementName</rootElement>
<uri>schemaURI</uri>
</xsdConnection>
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