help with DFDL XSD: parsing EDI to XML and wrapping elements

[Nestor Fernandez]

Hi team,

We have a requirement that some of the resulting XML elements after parsing
an EDIFACT file should be nested or wrapped by some grouping element.

Given an edi file with a flat structure like this:

segment1
segment2
segment3
segment4

our final goal would be to get an xml file with a more complex structure
such as this:

<xml>
    <segment1/>
    <segment-wrapper>
        <segment-wrapper>
            <segment2/>
            <segment3/>
        </segment-wrapper>
        <segment4/>
    </segment-wrapper>
</xml>

I know we could just use XSLT, but is it even possible just with Daffodil
libraries? I am new to DFDL, and thought this would be very simple, but all
things I tried have failed (either XSD is not valid, or I get daffodil
runtime errors). I am using apache-daffodil-3.1.0 command line interface.


I put together a more practical example:

INPUT EDI file:

HDR+1+0+59.97+64.92+4.95+Wed Nov 15 13?:45?:28 EST
2006'CUS+user1+Harry:Fletcher+SD'ORD+1+1+364+The 40-Year-Old
Virgin+29.98'ORD+2+1+299+Pulp Fiction+29.99'


DFDL XSD Schema file:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"; xmlns:dfdl="
http://www.ogf.org/dfdl/dfdl-1.0/"; xmlns:ibmEdiFmt="
http://www.ibm.com/dfdl/EDI/Format";>
    <xsd:import namespace="http://www.ibm.com/dfdl/EDI/Format";
schemaLocation="IBM_EDI_Format.xsd"/>
    <xsd:annotation>
        <xsd:appinfo source="http://www.ogf.org/dfdl/";>
            <dfdl:format ref="ibmEdiFmt:EDIFormat"/>
        </xsd:appinfo>
    </xsd:annotation>
    <xsd:element name="Order">
        <xsd:complexType>
            <xsd:sequence dfdl:initiatedContent="yes">
                <xsd:element dfdl:initiator="HDR"
dfdl:ref="ibmEdiFmt:EDISegmentFormat" name="header" type="HDR"/>
                <xsd:element dfdl:initiator="CUS"
dfdl:ref="ibmEdiFmt:EDISegmentFormat" name="customer-details" type="CUS"/>
                <xsd:element dfdl:initiator="ORD"
dfdl:ref="ibmEdiFmt:EDISegmentFormat" name="order-item"
maxOccurs="unbounded" type="ORD"/>
            </xsd:sequence>
        </xsd:complexType>
    </xsd:element>
    <xsd:complexType name="HDR">
        <xsd:sequence dfdl:ref="ibmEdiFmt:EDISegmentSequenceFormat">
            <xsd:element name="order-id" type="xsd:string"/>
            <xsd:element name="status-code" type="xsd:string"/>
            <xsd:element name="net-amount" type="xsd:string"/>
            <xsd:element name="total-amount" type="xsd:string"/>
            <xsd:element name="tax" type="xsd:string"/>
            <xsd:element name="date" type="xsd:string"/>
        </xsd:sequence>
    </xsd:complexType>
    <xsd:complexType name="CUS">
        <xsd:sequence dfdl:ref="ibmEdiFmt:EDISegmentSequenceFormat">
            <xsd:element name="username" type="xsd:string"/>
            <xsd:element name="name">
                <xsd:complexType>
                    <xsd:sequence
dfdl:ref="ibmEdiFmt:EDICompositeSequenceFormat">
                        <xsd:element name="firstname" type="xsd:string"/>
                        <xsd:element name="lastname" type="xsd:string"/>
                    </xsd:sequence>
                </xsd:complexType>
            </xsd:element>
            <xsd:element name="state" type="xsd:string"/>
        </xsd:sequence>
    </xsd:complexType>
    <xsd:complexType name="ORD">
        <xsd:sequence dfdl:ref="ibmEdiFmt:EDISegmentSequenceFormat">
            <xsd:element name="position" type="xsd:string"/>
            <xsd:element name="quantity" type="xsd:string"/>
            <xsd:element name="product-id" type="xsd:string"/>
            <xsd:element name="title" type="xsd:string"/>
            <xsd:element name="price" type="xsd:string"/>
        </xsd:sequence>
    </xsd:complexType>
</xsd:schema>


OUTPUT:

<Order>
    <header>
        <order-id>1</order-id>
        <status-code>0</status-code>
        <net-amount>59.97</net-amount>
        <total-amount>64.92</total-amount>
        <tax>4.95</tax>
        <date>Wed Nov 15 13:45:28 EST 2006</date>
    </header>
    <customer-details>
        <username>user1</username>
        <name>
            <firstname>Harry</firstname>
            <lastname>Fletcher</lastname>
        </name>
        <state>SD</state>
    </customer-details>
    <order-item>
        <position>1</position>
        <quantity>1</quantity>
        <product-id>364</product-id>
        <title>The 40-Year-Old Virgin</title>
        <price>29.98</price>
    </order-item>
    <order-item>
        <position>2</position>
        <quantity>1</quantity>
        <product-id>299</product-id>
        <title>Pulp Fiction</title>
        <price>29.99</price>
    </order-item>
</Order>


Let's say we want to nest XML elements (originally EDI segments), header
and custom-details, and get something similar to this:

EXAMPLE OF DESIRED OUTPUT:

<Order>
    <order-info>
        <header>
            <order-id>1</order-id>
            <status-code>0</status-code>
            <net-amount>59.97</net-amount>
            <total-amount>64.92</total-amount>
            <tax>4.95</tax>
            <date>Wed Nov 15 13:45:28 EST 2006</date>
        </header>
        <customer-details>
            <username>user1</username>
            <name>
                <firstname>Harry</firstname>
                <lastname>Fletcher</lastname>
            </name>
            <state>SD</state>
        </customer-details>
    </order-info>
    <order-item>
        <position>1</position>
        <quantity>1</quantity>
        <product-id>364</product-id>
        <title>The 40-Year-Old Virgin</title>
        <price>29.98</price>
    </order-item>
    <order-item>
        <position>2</position>
        <quantity>1</quantity>
        <product-id>299</product-id>
        <title>Pulp Fiction</title>
        <price>29.99</price>
    </order-item>
</Order>


Any ideas would be appreciated.

Thanks and regards