Josh English wrote:
Chris,
Thanks. This worked for the attributes, but I think the tactic is
still misleading. There are child elements I can't quite determine how
to deal with:
<market code='anlg' tier='ProMarket' mail='True'>
<title field="pref">Analog Science Fiction and Fact</title>
<nickname>Analog</nickname>
<keyword>Science Fiction</keyword>
<keyword>First Contact</keyword>
<keyword>Hard Science Fiction</keyword>
<address>
<attnline>Stanley Schmidt, Editor</attnline>
<address1>267 Broadway, 4th Floor</address1>
<address2>New York, NY 10007-2352</address2>
</address>
<website>http://www.analogsf.com</website>
</market>
A child element with text and an attribute or two, for example, pose a
problem. I can call Market.title but should I try Market.title.field
or Market.title_field.
Multiple elements, such as keywords, are allowed in xml but harder to
map to the object. I don't know if I want to go create a list and
methods for accessing those keywords as a list, or redefine the rules
of my XML to not allow multiple child elements with the same tag. I
can't decide.
Then the address is a bit of a bear.
In short, I have to figure out the whole object interface to the XML
and how I want that to work.
Have you heard of or considered PyXB (http://pyxb.sourceforge.net/)? Not
that I've much experience with it, but you can use it to generate python
code from XML Schema files, and, I think, WSDL definitions. It's a bit
of a rabbit hole, but then isn't that half the fun!
The following might give you the idea. You start with a Schema
schema.xsd, generate a python module from it, then read in some XML with
the generated classes to get your custom objects.
---------------- schema.xsd ----------------------
<xs:schema targetNamespace="http://www.josh.com/schema/0.1";
xmlns:xs="http://www.w3.org/2001/XMLSchema";
xmlns:josh="http://www.josh.com/schema/0.1";>
<xs:element name="market" type="josh:MarketType"/>
<xs:complexType name="MarketType">
<xs:sequence>
<xs:element name="title" type="josh:TitleType"/>
<xs:element name="nickname" type="xs:string"/>
<xs:element name="keyword" type="xs:string"
maxOccurs="unbounded"/>
<xs:element name="address" type="josh:USAddress"/>
<xs:element name="website" type="xs:string"/>
</xs:sequence>
<xs:attributeGroup ref="josh:MarketAttributes"/>
</xs:complexType>
<xs:complexType name="TitleType">
<xs:simpleContent>
<xs:extension base="xs:string">
<xs:attribute name="field" type="xs:string"/>
</xs:extension>
</xs:simpleContent>
</xs:complexType>
<xs:attributeGroup name="MarketAttributes">
<xs:attribute name="code" type="xs:string"/>
<xs:attribute name="tier" type="xs:string"/>
<xs:attribute name="mail" type="xs:string"/>
</xs:attributeGroup>
<xs:complexType name="Address" abstract="true">
<xs:sequence>
<xs:element name="name" type="xs:string"/>
<xs:element name="street" type="xs:string"/>
<xs:element name="city" type="xs:string"/>
</xs:sequence>
</xs:complexType>
<xs:complexType name="USAddress">
<xs:complexContent>
<xs:extension base="josh:Address">
<xs:sequence>
<xs:element name="state" type="josh:USState"
minOccurs="0"/>
<xs:element name="zip" type="xs:positiveInteger"
minOccurs="0"/>
</xs:sequence>
</xs:extension>
</xs:complexContent>
</xs:complexType>
<xs:simpleType name="USState">
<xs:restriction base="xs:string">
<xs:enumeration value="AK"/>
<xs:enumeration value="AL"/>
<xs:enumeration value="AR"/>
<!-- and so on ... -->
</xs:restriction>
</xs:simpleType>
</xs:schema>
---------------- genbindings.sh ---------------------------
#!/bin/sh
pyxbgen -u schema.xsd -m market_binding -r
---------------- demo.py -----------------------------------
s = """<?xml version="1.0"?>
<josh:market
xmlns:josh="http://www.josh.com/schema/0.1";
code="anlg"
tier="ProMarket"
mail="True">
<title field="pref">Analog Science Fiction and Fact</title>
<nickname>Analog</nickname>
<keyword>Science Fiction</keyword>
<keyword>First Contact</keyword>
<keyword>Hard Science Fiction</keyword>
<address>
<name>Stanley Schmidt, Editor</name>
<street>267 Broadway, 4th Floor</street>
<city>New York</city>
</address>
<website>http://www.analogsf.com</website>
</josh:market>
"""
import xml.dom.minidom
import market_binding
market =
market_binding.CreateFromDOM(xml.dom.minidom.parseString(s).documentElement)
print market.tier
print market.code
print market.keyword
assert len(market.keyword) == 3
print market.address.name
print market.toxml()
--
http://mail.python.org/mailman/listinfo/python-list
