Need action mechanism

New in version 7.0.

ir.needaction_mixin class

New in version openobject-server.4124.

This revision adds a mixin class for objects using the need action feature.

Need action feature can be used by objects willing to be able to signal that an action is required on a particular record. If in the business logic an action must be performed by somebody, for instance validation by a manager, this mechanism allows to set a list of users asked to perform an action.

This class wraps a class (ir.ir_needaction_users_rel) that behaves like a many2many field. However, no field is added to the model inheriting from ir.needaction_mixin. The mixin class manages the low-level considerations of updating relationships. Every change made on the record calls a method that updates the relationships.

Objects using the need_action feature should override the get_needaction_user_ids method. This methods returns a dictionary whose keys are record ids, and values a list of user ids, like in a many2many relationship. Therefore by defining only one method, you can specify if an action is required by defining the users that have to do it, in every possible situation.

This class also offers several global services,:
  • needaction_get_record_ids: for the current model and uid, get all record ids that ask this user to perform an action. This mechanism is used for instance to display the number of pending actions in menus, such as Leads (12)
  • needaction_get_action_count: as needaction_get_record_ids but returns only the number of action, not the ids (performs a search with count=True)
  • needaction_get_user_record_references: for a given uid, get all the records that ask this user to perform an action. Records are given as references, a list of tuples (model_name, record_id).

New in version openobject-server.4137.

This revision of the needaction_mixin mechanism slighty modifies the class behavior. The ir_needaction_mixin class now adds a function field on models inheriting from the class. This field allows to state whether a given record has a needaction for the current user. This is usefull if you want to customize views according to the needaction feature. For example, you may want to set records in bold in a list view if the current user has an action to perform on the record. This makes the class not a pure abstract class, but allows to easily use the action information. The field definition is:

def get_needaction_pending(self, cr, uid, ids, name, arg, context=None):
    res = {}
    needaction_user_ids = self.get_needaction_user_ids(cr, uid, ids, context=context)
    for id in ids:
        res[id] = uid in needaction_user_ids[id]
    return res

_columns = {
    'needaction_pending': fields.function(get_needaction_pending, type='boolean',
                    string='Need action pending',
                    help='If True, this field states that users have to perform an action. \
                            This field comes from the needaction mechanism. Please refer \
                            to the ir.needaction_mixin class.'),
}

ir.needaction_users_rel class

New in version openobject-server.4124.

This class essentially wraps a database table that behaves like a many2many. It holds data related to the needaction mechanism inside OpenERP. A row in this model is characterized by:

  • res_model: model of the record requiring an action
  • res_id: ID of the record requiring an action
  • user_id: foreign key to the res.users table, to the user that has to perform the action

This model can be seen as a many2many, linking (res_model, res_id) to users (those whose attention is required on the record)

Addon implementation example

In your foo module, you want to specify that when it is in state confirmed, it has to be validated by a manager, given by the field manager_id. After making foo inheriting from ir.needaction_mixin, you override the get_needaction_user_ids method:

[...]
_inherit = [`ir.needaction_mixin]
[...]
def get_needaction_user_ids(self, cr, uid, ids, context=None):
  result = dict.fromkeys(ids)
  for foo_obj in self.browse(cr, uid, ids, context=context):
    # set the list void by default
    result[foo_obj.id] = []
    # if foo_obj is confirmed: manager is required to perform an action
    if foo_obj.state == 'confirmed':
      result[foo_obj.id] = [foo_obj.manager_id]
  return result