# -*- coding: utf-8 -*-
##############################################################################
#
# Author: Guewen Baconnier
# Copyright 2013 Camptocamp SA
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
##############################################################################
"""
Mappers
=======
Mappers are the ConnectorUnit classes responsible to transform
external records into OpenERP records and conversely.
"""
import logging
from collections import namedtuple
from contextlib import contextmanager
from openerp import models
from ..connector import ConnectorUnit, MetaConnectorUnit, ConnectorEnvironment
from ..exception import MappingError, NoConnectorUnitError
_logger = logging.getLogger(__name__)
[docs]def mapping(func):
""" 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 OpenERP, 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_backend('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 callable(field):
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_backend(field, binding=None):
""" A modifier intended to be used on the ``direct`` mappings.
For a many2one, get the ID on the backend 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_backend('country_id', binding='magento.res.country'),
'country'),
(m2o_to_backend('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_backend(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 backend_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 OpenERP and returns its ID.
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 = [(backend_to_m2o('country', binding='magento.res.country'),
'country_id'),
(backend_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)
with self.session.change_context(active_test=False):
record = binder.to_openerp(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(ConnectorUnit):
""" 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 OpenERP or the
backend (as seen above with ``(0, 0, {values})``
A MapChild can be extended like any other
:py:class:`~connector.connector.ConnectorUnit`.
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`.
"""
_model_name = None
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
mapped.append(self.get_item_values(map_record, to_attr, options))
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(MapChild):
""" :py:class:`MapChild` for the Imports """
def _child_mapper(self):
return self.unit_for(ImportMapper)
[docs]class ExportMapChild(MapChild):
""" :py:class:`MapChild` for the Exports """
def _child_mapper(self):
return self.unit_for(ExportMapper)
[docs]class Mapper(ConnectorUnit):
""" A Mapper translates an external record to an OpenERP 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_backend`
* :py:func:`backend_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:`openerp.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 = Mapper(env)
map_record = mapper.map_record(record)
values = map_record.values()
values = map_record.values(only_create=True)
values = map_record.values(fields=['name', 'street'])
"""
__metaclass__ = MetaMapper
# name of the OpenERP model, to be defined in concrete classes
_model_name = None
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_class = None
def __init__(self, connector_env):
"""
:param connector_env: current environment (backend, session, ...)
:type connector_env: :py:class:`connector.connector.Environment`
"""
super(Mapper, self).__init__(connector_env)
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.iteritems():
yield getattr(self, meth), definition
def _get_map_child_unit(self, model_name):
try:
mapper_child = self.unit_for(self._map_child_class,
model=model_name)
except NoConnectorUnitError:
# does not force developers to use a MapChild ->
# will use the default one if not explicitely defined
env = ConnectorEnvironment(self.backend_record,
self.session,
model_name)
mapper_child = self._map_child_class(env)
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_class is not None, "_map_child_class required"
child_records = map_record.source[from_attr]
mapper_child = self._get_map_child_unit(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 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 callable(from_attr):
attr_name = MetaMapper._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 before returning them, as the
``on_change``.
: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(Mapper):
""" :py:class:`Mapper` for imports.
Transform a record from a backend to an OpenERP record
"""
_map_child_class = ImportMapChild
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 callable(from_attr):
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 backend_to_m2o in the 'direct' mappings to
# change that.
field = self.model._fields[to_attr]
if field.type == 'many2one':
mapping_func = backend_to_m2o(from_attr)
value = mapping_func(self, record, to_attr)
return value
[docs]class ExportMapper(Mapper):
""" :py:class:`Mapper` for exports.
Transform a record from OpenERP to a backend record
"""
_map_child_class = ExportMapChild
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 callable(from_attr):
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_backend in the 'direct' mappings to
# change that.
field = self.model._fields[from_attr]
if field.type == 'many2one':
mapping_func = m2o_to_backend(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::
mapper = SomeMapper(env)
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::
mapper = SomeMapper(env)
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::
mapper = SomeMapper(env)
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)
[docs]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