XSD Renderer¶

Papyrus provides an XSD renderer, capable of serializing SQLAlchemy mapped classes (including GeoAlchemy geometry columns) into XML Schema Documents.

XSDs generated by the XSD Renderer can, for example, be parsed using OpenLayers’s DescribeFeatureType format.

To use the XSD renderer the XSD renderer factory should be added to the application configuration.

This is done by either passing the factory to the Configurator constructor:

from pyramid.mako_templating import renderer_factory as mako_renderer_factory
from papyrus.renderers import XSD
config = Configurator(
    renderers=(('.mako', mako_renderer_factory),
               ('xsd', XSD()))
    )

Or by applying the add_renderer method to the Configurator instance:

from papyrus.renderers import XSD
config.add_renderer('xsd', XSD())

Make sure that add_renderer is called before any add_view call that names xsd as an argument.

To use the XSD renderer in a view set renderer to xsd in the view config. Here is a simple example:

from sqlalchemy import Column, types
from sqlalchemy.ext.declarative import declarative_base

Base = declarative_base()

@view_config(renderer='xsd')
def hello_world(request):
    class C(Base):
        __tablename__ = 'table'
        id = Column(types.Integer, primary_key=True)
    return C

Views configured with the xsd renderer should return SQLAlchemy mapped classes.

Here’s another example:

@view_config(renderer='xsd')
def spots_md(request):
    return Spot

Where Spot is an SQLAlchemy mapped class created using SQLAlchemy’s declarative layer.

Notes:

By default the XSD renderer skips columns which are primary keys. If you wish to include primary keys then pass include_primary_keys=True when creating the XSD objects, for example:
```
from papyrus.renderers import XSD
config.add_renderer('xsd', XSD(include_primary_keys=True))
```
By default the XSD renderer skips columns which are foreign keys. Use include_foreign_keys=True to change that behavior. For example:
```
from papyrus.renderers import XSD
config.add_renderer('xsd', XSD(include_foreign_keys=True))
```

The XSD renderer adds xsd:element nodes for the column properties it finds in the class. The XSD renderer will ignore other property types. For example it will ignore relationship properties and association proxies. If you want to add xsd:element nodes for other elements in the class then use a sequence_callback. For example:

from papyrus.renderers import XSD
def callback(tb, cls):
    attrs = {}
    attrs['minOccurs'] = str(0)
    attrs['nillable'] = 'true'
    attrs['name'] = 'gender'
    with tag(tb, 'xsd:element', attrs) as tb:
        with tag(tb, 'xsd:simpleType') as tb:
            with tag(tb, 'xsd:restriction', {'base': 'xsd:string'}) as tb:
                with tag(tb, 'xsd:enumeration', {'value': 'male'}):
                        pass
                with tag(tb, 'xsd:enumeration', {'value': 'female'}):
                        pass
config.add_renderer('xsd', XSD(sequence_callback=callback))

API Reference¶

class papyrus.renderers.XSD(include_primary_keys=False, include_foreign_keys=False, sequence_callback=None)[source]¶

XSD renderer.

An XSD renderer generate an XML schema document from an SQLAlchemy Table object.

Configure a XSD renderer using the add_renderer method on the Configurator object:

from papyrus.renderers import XSD

config.add_renderer('xsd', XSD())

Once this renderer has been registered as above , you can use xsd as the renderer parameter to @view_config or to the add_view method on the Configurator object:

from myapp.models import Spot

@view_config(renderer='xsd')
def myview(request):
    return Spot

By default, the XSD renderer will skip columns which are primary keys or foreign keys.

If you wish to include primary keys then pass include_primary_keys=True when creating the XSD object, for example:

from papyrus.renderers import XSD

config.add_renderer('xsd', XSD(include_primary_keys=True))

If you wish to include foreign keys then pass include_foreign_keys=True when creating the XSD object, for example:

from papyrus.renderers import XSD

config.add_renderer('xsd', XSD(include_foreign_keys=True))

The XSD renderer adds xsd:element nodes for the column properties it finds in the class. The XSD renderer will ignore other property types. For example it will ignore relationship properties and association proxies. If you want to add xsd:element nodes for other elements in the class then use a sequence_callback. For example:

The callback receives an xml.etree.ElementTree.TreeBuilder object and the mapped class being serialized.