Chapter 16: Substitution groups¶
Example 16-1 The head of a substitution group¶
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="items" type="ItemsType" />
<xs:complexType name="ItemsType">
<xs:sequence>
<xs:element ref="product" maxOccurs="unbounded" />
</xs:sequence>
</xs:complexType>
<xs:element name="product" type="ProductType" />
<xs:complexType name="ProductType">
<xs:sequence>
<xs:element name="number" type="xs:integer" />
<xs:element name="name" type="xs:string" />
</xs:sequence>
</xs:complexType>
</xs:schema>
from dataclasses import dataclass, field
from typing import List, Optional
@dataclass
class ProductType:
"""
:ivar number:
:ivar name:
"""
number: Optional[int] = field(
default=None,
metadata=dict(
name="number",
type="Element",
namespace="",
required=True
)
)
name: Optional[str] = field(
default=None,
metadata=dict(
name="name",
type="Element",
namespace="",
required=True
)
)
@dataclass
class Product(ProductType):
class Meta:
name = "product"
@dataclass
class ItemsType:
"""
:ivar product:
"""
product: List[Product] = field(
default_factory=list,
metadata=dict(
name="product",
type="Element",
namespace="",
min_occurs=1,
max_occurs=9223372036854775807
)
)
@dataclass
class Items(ItemsType):
class Meta:
name = "items"
Example 16-10 Using block to prevent substitution group use¶
<!-- SKIPTEST -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="product" type="ProductType" block="#all" />
<xs:element name="hat" type="HatType" block="substitution" />
</xs:schema>
Warning
Unsupported feature!
Example 16-11 An abstract element declaration¶
<!-- SKIPTEST -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="product" type="ProductType" abstract="true" />
</xs:schema>
Warning
Unsupported feature!
Example 16-2 Members of a substitution group¶
<!-- SKIPTEST: XML Schema 1.1 -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="shirt" type="ShirtType" substitutionGroup="product" />
<xs:complexType name="ShirtType">
<xs:complexContent>
<xs:extension base="ProductType">
<xs:sequence>
<xs:element name="size" type="ShirtSizeType" />
<xs:element name="color" type="xs:string" />
</xs:sequence>
</xs:extension>
</xs:complexContent>
</xs:complexType>
<xs:element name="hat" substitutionGroup="product">
<xs:complexType>
<xs:complexContent>
<xs:extension base="ProductType">
<xs:sequence>
<xs:element name="size" type="HatSizeType" />
</xs:sequence>
</xs:extension>
</xs:complexContent>
</xs:complexType>
</xs:element>
<xs:element name="umbrella" substitutionGroup="product" />
</xs:schema>
Warning
XML Schema 1.1
Example 16-4 Substitution group with simple types¶
<!-- SKIPTEST -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="number" />
<xs:element name="skuNumber" type="xs:string" substitutionGroup="number" />
<xs:element name="productID" type="xs:integer" substitutionGroup="number" />
</xs:schema>
Warning
Unsupported feature!
Example 16-5 A member of two substitution groups¶
<!-- SKIPTEST: XML Schema 1.1 -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="product" type="ProductType" />
<xs:element name="discontinuedProduct" type="ProductType" />
<xs:element name="hat" type="HatType" substitutionGroup="product" />
<xs:element name="shirt" type="ShirtType" substitutionGroup="product" />
<xs:element name="umbrella" type="UmbrellaType" substitutionGroup="product discontinuedProduct" />
</xs:schema>
Warning
XML Schema 1.1
Example 16-6 Using a choice group¶
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:include schemaLocation="../chapter16/example1607.xsd" />
<xs:element name="items" type="ItemsType" />
<xs:complexType name="ItemsType">
<xs:group ref="ProductGroup" maxOccurs="unbounded" />
</xs:complexType>
<xs:group name="ProductGroup">
<xs:choice>
<xs:element name="product" type="ProductType" />
<xs:element name="shirt" type="ShirtType" />
<xs:element name="hat" type="HatType" />
<xs:element name="umbrella" type="ProductType" />
</xs:choice>
</xs:group>
</xs:schema>
from dataclasses import dataclass, field
from typing import Optional
from tests.fixtures.defxmlschema.chapter16.example1607 import (
HatType,
ShirtType,
)
from tests.fixtures.defxmlschema.chapter22.example2207 import (
ProductType,
)
@dataclass
class ItemsType:
"""
:ivar product:
:ivar shirt:
:ivar hat:
:ivar umbrella:
"""
product: Optional[ProductType] = field(
default=None,
metadata=dict(
name="product",
type="Element",
namespace=""
)
)
shirt: Optional[ShirtType] = field(
default=None,
metadata=dict(
name="shirt",
type="Element",
namespace=""
)
)
hat: Optional[HatType] = field(
default=None,
metadata=dict(
name="hat",
type="Element",
namespace=""
)
)
umbrella: Optional[ProductType] = field(
default=None,
metadata=dict(
name="umbrella",
type="Element",
namespace=""
)
)
@dataclass
class Items(ItemsType):
class Meta:
name = "items"
Example 16-7 Defining derived types¶
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:include schemaLocation="../chapter22/example2207.xsd" />
<xs:complexType name="ShirtType">
<xs:complexContent>
<xs:extension base="ProductType">
<xs:sequence>
<xs:element name="size" type="xs:int" />
<xs:element name="color" type="xs:string" />
</xs:sequence>
</xs:extension>
</xs:complexContent>
</xs:complexType>
<xs:complexType name="HatType">
<xs:complexContent>
<xs:extension base="ProductType">
<xs:sequence>
<xs:element name="size" type="xs:int" />
</xs:sequence>
</xs:extension>
</xs:complexContent>
</xs:complexType>
<xs:complexType name="UmbrellaType">
<xs:complexContent>
<xs:extension base="ProductType" />
</xs:complexContent>
</xs:complexType>
</xs:schema>
from dataclasses import dataclass, field
from typing import Optional
from tests.fixtures.defxmlschema.chapter22.example2207 import (
ProductType,
)
@dataclass
class HatType(ProductType):
"""
:ivar size:
"""
size: Optional[int] = field(
default=None,
metadata=dict(
name="size",
type="Element",
namespace="",
required=True
)
)
@dataclass
class ShirtType(ProductType):
"""
:ivar size:
:ivar color:
"""
size: Optional[int] = field(
default=None,
metadata=dict(
name="size",
type="Element",
namespace="",
required=True
)
)
color: Optional[str] = field(
default=None,
metadata=dict(
name="color",
type="Element",
namespace="",
required=True
)
)
@dataclass
class UmbrellaType(ProductType):
pass
Example 16-9 Using final to control substitution group declaration¶
<!-- SKIPTEST -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="product" type="ProductType" final="#all" />
<xs:element name="items" type="ItemsType" final="extension" />
<xs:element name="color" type="xs:string" final="restriction" />
<xs:element name="size" type="SizeType" final="" />
</xs:schema>
Warning
Unsupported feature!
Samples Source
Definitive XML Schema by Priscilla Walmsley (c) 2012 Prentice Hall PTR