xmlschema 3.4.1

Description:

xmlschema 3.4.1

The xmlschema library is an implementation of XML Schema
for Python (supports Python 3.8+).
This library arises from the needs of a solid Python layer for processing XML
Schema based files for
MaX (Materials design at the Exascale) European project.
A significant problem is the encoding and the decoding of the XML data files
produced by different simulation software.
Another important requirement is the XML data validation, in order to put the
produced data under control. The lack of a suitable alternative for Python in
the schema-based decoding of XML data has led to build this library. Obviously
this library can be useful for other cases related to XML Schema based processing,
not only for the original scope.
The full xmlschema documentation is available on “Read the Docs”.

Features
This library includes the following features:

Full XSD 1.0 and XSD 1.1 support
Building of XML schema objects from XSD files
Validation of XML instances against XSD schemas
Decoding of XML data into Python data and to JSON
Encoding of Python data and JSON to XML
Data decoding and encoding ruled by converter classes
An XPath based API for finding schema’s elements and attributes
Support of XSD validation modes strict/lax/skip
XML attacks protection using an XMLParser that forbids entities
Access control on resources addressed by an URL or filesystem path
Downloading XSD files from a remote URL and storing them for offline use
XML data bindings based on DataElement class
Static code generation with Jinja2 templates



Installation
You can install the library with pip in a Python 3.7+ environment:
pip install xmlschema
The library uses the Python’s ElementTree XML library and requires
elementpath additional package.
The base schemas of the XSD standards are included in the package for working
offline and to speed-up the building of schema instances.


Usage
Import the library and then create a schema instance using the path of
the file containing the schema as argument:
>>> import xmlschema
>>> my_schema = xmlschema.XMLSchema('tests/test_cases/examples/vehicles/vehicles.xsd')

Note
For XSD 1.1 schemas use the class XMLSchema11, because the default class
XMLSchema is an alias of the XSD 1.0 validator class XMLSchema10.

The schema can be used to validate XML documents:
>>> my_schema.is_valid('tests/test_cases/examples/vehicles/vehicles.xml')
True
>>> my_schema.is_valid('tests/test_cases/examples/vehicles/vehicles-1_error.xml')
False
>>> my_schema.validate('tests/test_cases/examples/vehicles/vehicles-1_error.xml')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/brunato/Development/projects/xmlschema/xmlschema/validators/xsdbase.py", line 393, in validate
raise error
xmlschema.validators.exceptions.XMLSchemaValidationError: failed validating <Element '{http://example.com/vehicles}cars' at 0x7f8032768458> with XsdGroup(model='sequence').

Reason: character data between child elements not allowed!

Schema:

<xs:sequence xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element maxOccurs="unbounded" minOccurs="0" name="car" type="vh:vehicleType" />
</xs:sequence>

Instance:

<vh:cars xmlns:vh="http://example.com/vehicles">
NOT ALLOWED CHARACTER DATA
<vh:car make="Porsche" model="911" />
<vh:car make="Porsche" model="911" />
</vh:cars>
Using a schema you can also decode the XML documents to nested dictionaries, with
values that match to the data types declared by the schema:
>>> import xmlschema
>>> from pprint import pprint
>>> xs = xmlschema.XMLSchema('tests/test_cases/examples/collection/collection.xsd')
>>> pprint(xs.to_dict('tests/test_cases/examples/collection/collection.xml'))
{'@xsi:schemaLocation': 'http://example.com/ns/collection collection.xsd',
'object': [{'@available': True,
'@id': 'b0836217462',
'author': {'@id': 'PAR',
'born': '1841-02-25',
'dead': '1919-12-03',
'name': 'Pierre-Auguste Renoir',
'qualification': 'painter'},
'estimation': Decimal('10000.00'),
'position': 1,
'title': 'The Umbrellas',
'year': '1886'},
{'@available': True,
'@id': 'b0836217463',
'author': {'@id': 'JM',
'born': '1893-04-20',
'dead': '1983-12-25',
'name': 'Joan Miró',
'qualification': 'painter, sculptor and ceramicist'},
'position': 2,
'title': None,
'year': '1925'}]}


Authors
Davide Brunato and others who have contributed with code or with sample cases.


License
This software is distributed under the terms of the MIT License.
See the file ‘LICENSE’ in the root directory of the present
distribution, or http://opensource.org/licenses/MIT.