# -*- coding: utf-8 -*-
# Copyright 2017 Camptocamp SA
# License LGPL-3.0 or later (http://www.gnu.org/licenses/lgpl.html)
"""
Mappers
=======
Mappers are the components responsible to transform
external records into Odoo records and conversely.
"""
import logging
from collections import namedtuple
from contextlib import contextmanager
from odoo import models
from odoo.addons.component.core import AbstractComponent
from odoo.addons.component.exception import NoComponentError
from ..exception import MappingError
import collections
_logger = logging.getLogger(__name__)
__all__ = [
'Mapper', 'ImportMapper', 'ExportMapper', 'mapping',
'changed_by', 'only_create', 'none', 'convert',
'm2o_to_external', 'external_to_m2o', 'follow_m2o_relations',
'MapRecord', 'MapChild', 'ImportMapChild', 'ExportMapChild',
]
[docs]def mapping(func):
""" Decorator, declare that a method is a mapping method.
It is then used by the :py:class:`Mapper` to convert the records.
Usage::
@mapping
def any(self, record):
return {'output_field': record['input_field']}
"""
func.is_mapping = True
return func
[docs]def changed_by(*args):
""" Decorator for the mapping methods (:py:func:`mapping`)
When fields are modified in Odoo, we want to export only the
modified fields. Using this decorator, we can specify which fields
updates should trigger which mapping method.
If ``changed_by`` is empty, the mapping is always active.
As far as possible, this decorator should be used for the exports,
thus, when we do an update on only a small number of fields on a
record, the size of the output record will be limited to only the
fields really having to be exported.
Usage::
@changed_by('input_field')
@mapping
def any(self, record):
return {'output_field': record['input_field']}
:param ``*args``: field names which trigger the mapping when modified
"""
def register_mapping(func):
func.changed_by = args
return func
return register_mapping
[docs]def only_create(func):
""" Decorator for the mapping methods (:py:func:`mapping`)
A mapping decorated with ``only_create`` means that it has to be
used only for the creation of the records.
Usage::
@only_create
@mapping
def any(self, record):
return {'output_field': record['input_field']}
"""
func.only_create = True
return func
[docs]def none(field):
""" A modifier intended to be used on the ``direct`` mappings.
Replace the False-ish values by None.
It can be used in a pipeline of modifiers when .
Example::
direct = [(none('source'), 'target'),
(none(m2o_to_external('rel_id'), 'rel_id')]
:param field: name of the source field in the record
:param binding: True if the relation is a binding record
"""
def modifier(self, record, to_attr):
if isinstance(field, collections.Callable):
result = field(self, record, to_attr)
else:
result = record[field]
if not result:
return None
return result
return modifier
[docs]def convert(field, conv_type):
""" A modifier intended to be used on the ``direct`` mappings.
Convert a field's value to a given type.
Example::
direct = [(convert('source', str), 'target')]
:param field: name of the source field in the record
:param binding: True if the relation is a binding record
"""
def modifier(self, record, to_attr):
value = record[field]
if not value:
return False
return conv_type(value)
return modifier
[docs]def m2o_to_external(field, binding=None):
""" A modifier intended to be used on the ``direct`` mappings.
For a many2one, get the external ID and returns it.
When the field's relation is not a binding (i.e. it does not point to
something like ``magento.*``), the binding model needs to be provided
in the ``binding`` keyword argument.
Example::
direct = [(m2o_to_external('country_id',
binding='magento.res.country'), 'country'),
(m2o_to_external('magento_country_id'), 'country')]
:param field: name of the source field in the record
:param binding: name of the binding model is the relation is not a binding
"""
def modifier(self, record, to_attr):
if not record[field]:
return False
column = self.model._fields[field]
if column.type != 'many2one':
raise ValueError('The column %s should be a Many2one, got %s' %
(field, type(column)))
rel_id = record[field].id
if binding is None:
binding_model = column.comodel_name
else:
binding_model = binding
binder = self.binder_for(binding_model)
# if a relation is not a binding, we wrap the record in the
# binding, we'll return the id of the binding
wrap = bool(binding)
value = binder.to_external(rel_id, wrap=wrap)
if not value:
raise MappingError("Can not find an external id for record "
"%s in model %s %s wrapping" %
(rel_id, binding_model,
'with' if wrap else 'without'))
return value
return modifier
[docs]def external_to_m2o(field, binding=None):
""" A modifier intended to be used on the ``direct`` mappings.
For a field from a backend which is an ID, search the corresponding
binding in Odoo and returns it.
When the field's relation is not a binding (i.e. it does not point to
something like ``magento.*``), the binding model needs to be provided
in the ``binding`` keyword argument.
Example::
direct = [(external_to_m2o('country', binding='magento.res.country'),
'country_id'),
(external_to_m2o('country'), 'magento_country_id')]
:param field: name of the source field in the record
:param binding: name of the binding model is the relation is not a binding
"""
def modifier(self, record, to_attr):
if not record[field]:
return False
column = self.model._fields[to_attr]
if column.type != 'many2one':
raise ValueError('The column %s should be a Many2one, got %s' %
(to_attr, type(column)))
rel_id = record[field]
if binding is None:
binding_model = column.comodel_name
else:
binding_model = binding
binder = self.binder_for(binding_model)
# if we want the normal record, not a binding,
# we ask to the binder to unwrap the binding
unwrap = bool(binding)
record = binder.to_internal(rel_id, unwrap=unwrap)
if not record:
raise MappingError("Can not find an existing %s for external "
"record %s %s unwrapping" %
(binding_model, rel_id,
'with' if unwrap else 'without'))
if isinstance(record, models.BaseModel):
return record.id
else:
_logger.debug(
'Binder for %s returned an id, '
'returning a record should be preferred.', binding_model
)
return record
return modifier
[docs]def follow_m2o_relations(field):
"""A modifier intended to be used on ``direct`` mappings.
'Follows' Many2one relations and return the final field value.
Examples:
Assuming model is ``product.product``::
direct = [
(follow_m2o_relations('product_tmpl_id.categ_id.name'), 'cat')]
:param field: field "path", using dots for relations as usual in Odoo
"""
def modifier(self, record, to_attr):
attrs = field.split('.')
value = record
for attr in attrs:
value = getattr(value, attr)
return value
return modifier
MappingDefinition = namedtuple('MappingDefinition',
['changed_by',
'only_create'])
[docs]class MapChild(AbstractComponent):
""" MapChild is responsible to convert items.
Items are sub-records of a main record.
In this example, the items are the records in ``lines``::
sales = {'name': 'SO10',
'lines': [{'product_id': 1, 'quantity': 2},
{'product_id': 2, 'quantity': 2}]}
A MapChild is always called from another :py:class:`Mapper` which
provides a ``children`` configuration.
Considering the example above, the "main" :py:class:`Mapper` would
returns something as follows::
{'name': 'SO10',
'lines': [(0, 0, {'product_id': 11, 'quantity': 2}),
(0, 0, {'product_id': 12, 'quantity': 2})]}
A MapChild is responsible to:
* Find the :py:class:`Mapper` to convert the items
* Possibly filter out some lines (can be done by inheriting
:py:meth:`skip_item`)
* Convert the items' records using the found :py:class:`Mapper`
* Format the output values to the format expected by Odoo or the
backend (as seen above with ``(0, 0, {values})``
A MapChild can be extended like any other
:py:class:`~component.core.Component`.
However, it is not mandatory to explicitly create a MapChild for
each children mapping, the default one will be used
(:py:class:`ImportMapChild` or :py:class:`ExportMapChild`).
The implementation by default does not take care of the updates: if
I import a sales order 2 times, the lines will be duplicated. This
is not a problem as long as an importation should only support the
creation (typical for sales orders). It can be implemented on a
case-by-case basis by inheriting :py:meth:`get_item_values` and
:py:meth:`format_items`.
"""
_name = 'base.map.child'
_inherit = 'base.connector'
def _child_mapper(self):
raise NotImplementedError
[docs] def skip_item(self, map_record):
""" Hook to implement in sub-classes when some child
records should be skipped.
The parent record is accessible in ``map_record``.
If it returns True, the current child record is skipped.
:param map_record: record that we are converting
:type map_record: :py:class:`MapRecord`
"""
return False
[docs] def get_items(self, items, parent, to_attr, options):
""" Returns the formatted output values of items from a main record
:param items: list of item records
:type items: list
:param parent: parent record
:param to_attr: destination field (can be used for introspecting
the relation)
:type to_attr: str
:param options: dict of options, herited from the main mapper
:return: formatted output values for the item
"""
mapper = self._child_mapper()
mapped = []
for item in items:
map_record = mapper.map_record(item, parent=parent)
if self.skip_item(map_record):
continue
item_values = self.get_item_values(map_record, to_attr, options)
if item_values:
mapped.append(item_values)
return self.format_items(mapped)
[docs] def get_item_values(self, map_record, to_attr, options):
""" Get the raw values from the child Mappers for the items.
It can be overridden for instance to:
* Change options
* Use a :py:class:`~connector.connector.Binder` to know if an
item already exists to modify an existing item, rather than to
add it
:param map_record: record that we are converting
:type map_record: :py:class:`MapRecord`
:param to_attr: destination field (can be used for introspecting
the relation)
:type to_attr: str
:param options: dict of options, herited from the main mapper
"""
return map_record.values(**options)
[docs]class ImportMapChild(AbstractComponent):
""" :py:class:`MapChild` for the Imports """
_name = 'base.map.child.import'
_inherit = 'base.map.child'
_usage = 'import.map.child'
def _child_mapper(self):
return self.component(usage='import.mapper')
[docs]class ExportMapChild(AbstractComponent):
""" :py:class:`MapChild` for the Exports """
_name = 'base.map.child.export'
_inherit = 'base.map.child'
_usage = 'export.map.child'
def _child_mapper(self):
return self.component(usage='export.mapper')
[docs]class Mapper(AbstractComponent):
""" A Mapper translates an external record to an Odoo record and
conversely. The output of a Mapper is a ``dict``.
3 types of mappings are supported:
Direct Mappings
Example::
direct = [('source', 'target')]
Here, the ``source`` field will be copied in the ``target`` field.
A modifier can be used in the source item.
The modifier will be applied to the source field before being
copied in the target field.
It should be a closure function respecting this idiom::
def a_function(field):
''' ``field`` is the name of the source field.
Naming the arg: ``field`` is required for the conversion'''
def modifier(self, record, to_attr):
''' self is the current Mapper,
record is the current record to map,
to_attr is the target field'''
return record[field]
return modifier
And used like that::
direct = [
(a_function('source'), 'target'),
]
A more concrete example of modifier::
def convert(field, conv_type):
''' Convert the source field to a defined ``conv_type``
(ex. str) before returning it'''
def modifier(self, record, to_attr):
value = record[field]
if not value:
return None
return conv_type(value)
return modifier
And used like that::
direct = [
(convert('myfield', float), 'target_field'),
]
More examples of modifiers:
* :py:func:`convert`
* :py:func:`m2o_to_external`
* :py:func:`external_to_m2o`
Method Mappings
A mapping method allows to execute arbitrary code and return one
or many fields::
@mapping
def compute_state(self, record):
# compute some state, using the ``record`` or not
state = 'pending'
return {'state': state}
We can also specify that a mapping methods should be applied
only when an object is created, and never applied on further
updates::
@only_create
@mapping
def default_warehouse(self, record):
# get default warehouse
warehouse_id = ...
return {'warehouse_id': warehouse_id}
Submappings
When a record contains sub-items, like the lines of a sales order,
we can convert the children using another Mapper::
children = [('items', 'line_ids', 'model.name')]
It allows to create the sales order and all its lines with the
same call to :py:meth:`odoo.models.BaseModel.create()`.
When using ``children`` for items of a record, we need to create
a :py:class:`Mapper` for the model of the items, and optionally a
:py:class:`MapChild`.
Usage of a Mapper::
>>> mapper = self.component(usage='mapper')
>>> map_record = mapper.map_record(record)
>>> values = map_record.values()
>>> values = map_record.values(only_create=True)
>>> values = map_record.values(fields=['name', 'street'])
Example of making 'children' records as 'create_only'::
class FooSaleOrderMapper(Component):
_name = 'foo.sale.order.import.mapper'
_inherit = 'foo.import.mapper'
_apply_on = 'foo.sale.order'
children = [('items', 'line_ids', 'foo.sale.order.line')]
class SaleLineMapChild(Component):
_name = 'foo.sale.line.import.map.child'
_inherit = ['foo.connector', 'base.map.child.import']
_apply_on = 'foo.sale.order.line'
def skip_item(self, map_record):
record = map_record.source
if not record['attributes']['quantity']:
return True
def get_item_values(self, map_record, to_attr, options):
values = map_record.values(**options)
binder = self.binder_for()
binding = binder.to_internal(map_record.source['id'])
if binding:
# already exists, keeps the id
values['id'] = binding.id
return values
def format_items(self, items_values):
# if we already have an ID (found in get_item_values())
# we change the command to update the existing record
items = []
for item in items_values[:]:
if item.get('id'):
binding_id = item.pop('id')
# update the record
items.append((1, binding_id, item))
else:
# create the record
items.append((0, 0, item))
return items
"""
_name = 'base.mapper'
_inherit = 'base.connector'
_usage = 'mapper'
direct = [] # direct conversion of a field to another (from_attr, to_attr)
children = [] # conversion of sub-records (from_attr, to_attr, model)
_map_methods = None
_map_child_usage = None
_map_child_fallback = None
@classmethod
def _build_mapper_component(cls):
""" Build a Mapper component
When a Mapper component is built, we will look into every of its bases
and look for methods decorated by ``@mapping`` or ``@changed_by``. We
keep the definitions in a ``_map_methods`` attribute for later use by
the Mapper instances.
The ``__bases__`` of a newly generated Component are of 2 kinds:
* other dynamically generated components (below 'base' and
'second.mapper')
* "real" Python classes applied on top of existing components (here
ThirdMapper)
::
>>> cls.__bases__
(<class 'odoo.addons.connector.tests.test_mapper.ThirdMapper'>,
<class 'odoo.addons.component.core.second.mapper'>,
<class 'odoo.addons.component.core.base'>)
This method traverses these bases, from the bottom to the top, and
merges the mapping definitions. It reuses the computed definitions
for the generated components (for which this code already ran), and
inspect the real classes to find mapping methods.
"""
map_methods = {}
for base in reversed(cls.__bases__):
if hasattr(base, '_map_methods'):
# this is already a dynamically generated Component, so we can
# use it's existing mappings
base_map_methods = base._map_methods or {}
for attr_name, definition in base_map_methods.items():
if attr_name in map_methods:
# Update the existing @changed_by with the content
# of each base (it is mutated in place).
mapping_changed_by = map_methods[attr_name].changed_by
mapping_changed_by.update(definition.changed_by)
# keep the last value for @only_create
if definition.only_create:
new_definition = MappingDefinition(
mapping_changed_by,
definition.only_create,
)
map_methods[attr_name] = new_definition
else:
map_methods[attr_name] = definition
else:
# this is a real class that needs to be applied upon
# the base Components
for attr_name in dir(base):
attr = getattr(base, attr_name, None)
if not getattr(attr, 'is_mapping', None):
continue
has_only_create = getattr(attr, 'only_create', False)
mapping_changed_by = set(getattr(attr, 'changed_by', ()))
# if already existing, it has been defined in an previous
# base, extend the @changed_by set
if map_methods.get(attr_name) is not None:
definition = map_methods[attr_name]
mapping_changed_by.update(definition.changed_by)
# keep the last choice for only_create
definition = MappingDefinition(mapping_changed_by,
has_only_create)
map_methods[attr_name] = definition
cls._map_methods = map_methods
@classmethod
def _complete_component_build(cls):
super(Mapper, cls)._complete_component_build()
cls._build_mapper_component()
def __init__(self, work):
super(Mapper, self).__init__(work)
self._options = None
def _map_direct(self, record, from_attr, to_attr):
""" Apply the ``direct`` mappings.
:param record: record to convert from a source to a target
:param from_attr: name of the source attribute or a callable
:type from_attr: callable | str
:param to_attr: name of the target attribute
:type to_attr: str
"""
raise NotImplementedError
def _map_children(self, record, attr, model):
raise NotImplementedError
@property
def map_methods(self):
""" Yield all the methods decorated with ``@mapping`` """
for meth, definition in self._map_methods.items():
yield getattr(self, meth), definition
def _get_map_child_component(self, model_name):
try:
mapper_child = self.component(usage=self._map_child_usage,
model_name=model_name)
except NoComponentError:
assert self._map_child_fallback is not None, (
"_map_child_fallback required")
# does not force developers to use a MapChild ->
# will use the default one if not explicitely defined
mapper_child = self.component_by_name(
self._map_child_fallback,
model_name=model_name
)
return mapper_child
def _map_child(self, map_record, from_attr, to_attr, model_name):
""" Convert items of the record as defined by children """
assert self._map_child_usage is not None, "_map_child_usage required"
child_records = map_record.source[from_attr]
mapper_child = self._get_map_child_component(model_name)
items = mapper_child.get_items(child_records, map_record,
to_attr, options=self.options)
return items
@contextmanager
def _mapping_options(self, options):
""" Change the mapping options for the Mapper.
Context Manager to use in order to alter the behavior
of the mapping, when using ``_apply`` or ``finalize``.
"""
current = self._options
self._options = options
yield
self._options = current
@property
def options(self):
""" Options can be accessed in the mapping methods with
``self.options``. """
return self._options
[docs] def changed_by_fields(self):
""" Build a set of fields used by the mapper
It takes in account the ``direct`` fields and the fields used by
the decorator: ``changed_by``.
"""
changed_by = set()
if getattr(self, 'direct', None):
for from_attr, __ in self.direct:
fieldname = self._direct_source_field_name(from_attr)
changed_by.add(fieldname)
for method_name, method_def in self._map_methods.items():
changed_by |= method_def.changed_by
return changed_by
def _direct_source_field_name(self, direct_entry):
""" Get the mapping field name. Goes through the function modifiers.
Ex::
[(none(convert(field_name, str)), out_field_name)]
It assumes that the modifier has ``field`` as first argument like::
def modifier(field, args):
"""
fieldname = direct_entry
if isinstance(direct_entry, collections.Callable):
# Map the closure entries with variable names
cells = dict(list(zip(
direct_entry.__code__.co_freevars,
(c.cell_contents for c in direct_entry.__closure__))))
assert 'field' in cells, "Modifier without 'field' argument."
if isinstance(cells['field'], collections.Callable):
fieldname = self._direct_source_field_name(cells['field'])
else:
fieldname = cells['field']
return fieldname
[docs] def map_record(self, record, parent=None):
""" Get a :py:class:`MapRecord` with record, ready to be
converted using the current Mapper.
:param record: record to transform
:param parent: optional parent record, for items
"""
return MapRecord(self, record, parent=parent)
def _apply(self, map_record, options=None):
""" Apply the mappings on a :py:class:`MapRecord`
:param map_record: source record to convert
:type map_record: :py:class:`MapRecord`
"""
if options is None:
options = {}
with self._mapping_options(options):
return self._apply_with_options(map_record)
def _apply_with_options(self, map_record):
""" Apply the mappings on a :py:class:`MapRecord` with
contextual options (the ``options`` given in
:py:meth:`MapRecord.values()` are accessible in
``self.options``)
:param map_record: source record to convert
:type map_record: :py:class:`MapRecord`
"""
assert self.options is not None, (
"options should be defined with '_mapping_options'")
_logger.debug('converting record %s to model %s',
map_record.source, self.model)
fields = self.options.fields
for_create = self.options.for_create
result = {}
for from_attr, to_attr in self.direct:
if isinstance(from_attr, collections.Callable):
attr_name = self._direct_source_field_name(from_attr)
else:
attr_name = from_attr
if (not fields or attr_name in fields):
value = self._map_direct(map_record.source,
from_attr,
to_attr)
result[to_attr] = value
for meth, definition in self.map_methods:
mapping_changed_by = definition.changed_by
if (not fields or not mapping_changed_by or
mapping_changed_by.intersection(fields)):
if definition.only_create and not for_create:
continue
values = meth(map_record.source)
if not values:
continue
if not isinstance(values, dict):
raise ValueError('%s: invalid return value for the '
'mapping method %s' % (values, meth))
result.update(values)
for from_attr, to_attr, model_name in self.children:
if (not fields or from_attr in fields):
result[to_attr] = self._map_child(map_record, from_attr,
to_attr, model_name)
return self.finalize(map_record, result)
[docs] def finalize(self, map_record, values):
""" Called at the end of the mapping.
Can be used to modify the values generated by all the mappings before
returning them.
:param map_record: source map_record
:type map_record: :py:class:`MapRecord`
:param values: mapped values
:returns: mapped values
:rtype: dict
"""
return values
[docs]class ImportMapper(AbstractComponent):
""" :py:class:`Mapper` for imports.
Transform a record from a backend to an Odoo record
"""
_name = 'base.import.mapper'
_inherit = 'base.mapper'
_usage = 'import.mapper'
_map_child_usage = 'import.map.child'
_map_child_fallback = 'base.map.child.import'
def _map_direct(self, record, from_attr, to_attr):
""" Apply the ``direct`` mappings.
:param record: record to convert from a source to a target
:param from_attr: name of the source attribute or a callable
:type from_attr: callable | str
:param to_attr: name of the target attribute
:type to_attr: str
"""
if isinstance(from_attr, collections.Callable):
return from_attr(self, record, to_attr)
value = record.get(from_attr)
if not value:
return False
# Backward compatibility: when a field is a relation, and a modifier is
# not used, we assume that the relation model is a binding.
# Use an explicit modifier external_to_m2o in the 'direct' mappings to
# change that.
field = self.model._fields[to_attr]
if field.type == 'many2one':
mapping_func = external_to_m2o(from_attr)
value = mapping_func(self, record, to_attr)
return value
[docs]class ExportMapper(AbstractComponent):
""" :py:class:`Mapper` for exports.
Transform a record from Odoo to a backend record
"""
_name = 'base.export.mapper'
_inherit = 'base.mapper'
_usage = 'export.mapper'
_map_child_usage = 'export.map.child'
_map_child_fallback = 'base.map.child.export'
def _map_direct(self, record, from_attr, to_attr):
""" Apply the ``direct`` mappings.
:param record: record to convert from a source to a target
:param from_attr: name of the source attribute or a callable
:type from_attr: callable | str
:param to_attr: name of the target attribute
:type to_attr: str
"""
if isinstance(from_attr, collections.Callable):
return from_attr(self, record, to_attr)
value = record[from_attr]
if not value:
return False
# Backward compatibility: when a field is a relation, and a modifier is
# not used, we assume that the relation model is a binding.
# Use an explicit modifier m2o_to_external in the 'direct' mappings to
# change that.
field = self.model._fields[from_attr]
if field.type == 'many2one':
mapping_func = m2o_to_external(from_attr)
value = mapping_func(self, record, to_attr)
return value
[docs]class MapRecord(object):
""" A record prepared to be converted using a :py:class:`Mapper`.
MapRecord instances are prepared by :py:meth:`Mapper.map_record`.
Usage::
>>> map_record = mapper.map_record(record)
>>> output_values = map_record.values()
See :py:meth:`values` for more information on the available arguments.
"""
def __init__(self, mapper, source, parent=None):
self._source = source
self._mapper = mapper
self._parent = parent
self._forced_values = {}
@property
def source(self):
""" Source record to be converted """
return self._source
@property
def parent(self):
""" Parent record if the current record is an item """
return self._parent
[docs] def values(self, for_create=None, fields=None, **kwargs):
""" Build and returns the mapped values according to the options.
Usage::
>>> map_record = mapper.map_record(record)
>>> output_values = map_record.values()
Creation of records
When using the option ``for_create``, only the mappings decorated
with ``@only_create`` will be mapped.
::
>>> output_values = map_record.values(for_create=True)
Filter on fields
When using the ``fields`` argument, the mappings will be
filtered using either the source key in ``direct`` arguments,
either the ``changed_by`` arguments for the mapping methods.
::
>>> output_values = map_record.values(
fields=['name', 'street']
)
Custom options
Arbitrary key and values can be defined in the ``kwargs``
arguments. They can later be used in the mapping methods
using ``self.options``.
::
>>> output_values = map_record.values(tax_include=True)
:param for_create: specify if only the mappings for creation
(``@only_create``) should be mapped.
:type for_create: boolean
:param fields: filter on fields
:type fields: list
:param ``**kwargs``: custom options, they can later be used in the
mapping methods
"""
options = MapOptions(for_create=for_create, fields=fields, **kwargs)
values = self._mapper._apply(self, options=options)
values.update(self._forced_values)
return values
[docs] def update(self, *args, **kwargs):
""" Force values to be applied after a mapping.
Usage::
>>> map_record = mapper.map_record(record)
>>> map_record.update(a=1)
>>> output_values = map_record.values()
# output_values will at least contain {'a': 1}
The values assigned with ``update()`` are in any case applied,
they have a greater priority than the mapping values.
"""
self._forced_values.update(*args, **kwargs)
class MapOptions(dict):
""" Container for the options of mappings.
Options can be accessed using attributes of the instance. When an
option is accessed and does not exist, it returns None.
"""
def __getitem__(self, key):
try:
return super(MapOptions, self).__getitem__(key)
except KeyError:
return None
def __getattr__(self, key):
return self[key]
def __setattr__(self, key, value):
self[key] = value