[ADD] project: recurring tasks

closes odoo/documentation#4260

Id: 3255317
Signed-off-by: Xavier Platteau (xpl) <xpl@odoo.com>

content/applications/services/project/tasks.rst

@@ -8,3 +8,4 @@ Tasks
    :titlesonly:
 
    tasks/email_alias
+   tasks/recurring_tasks

content/applications/services/project/tasks/recurring_tasks.rst

@@ -0,0 +1,53 @@
+===============
+Recurring tasks
+===============
+
+When handling a project, the same task often needs to be performed several times: for example,
+weekly meetings or status reports. The **recurring tasks** feature allows you to automate the
+creation of those tasks.
+
+.. seealso::
+   `Odoo Tutorials: Recurring tasks <https://www.odoo.com/slides/slide/recurring-tasks-1946>`_
+
+Configuration
+=============
+
+To enable recurring tasks, go to :menuselection:`Project --> Configuration --> Settings`,
+then activate :guilabel:`Recurring Tasks`, and :guilabel:`Save`.
+
+Recurring tasks are now activated on all existing projects. The feature can be deactivated
+on an individual project by clicking the drop-down menu button :guilabel:`⋮` next to the project
+name, then going to :menuselection:`Settings --> Settings --> Task Management` and disabling
+:guilabel:`Recurring Tasks`.
+
+Set up task recurrence
+----------------------
+
+In an existing task, go to the :guilabel:`Recurrent` tab, then check the :guilabel:`Recurrent` box.
+A set of options allows you to configure the frequency: :guilabel:`Days`, :guilabel:`Weeks`,
+:guilabel:`Months`, :guilabel:`Years`, and the number of repetitions.
+
+On the scheduled recurrency date, a new task is created on your project dashboard with the following
+configuration:
+
+- :guilabel:`Stage`: first stage of the project dashboard (:guilabel:`New` or equivalent);
+- :guilabel:`Name`, :guilabel:`Description`, :guilabel:`Project`, :guilabel:`Assignees`,
+  :guilabel:`Customer`, :guilabel:`Tags`: copied from the original task;
+- :guilabel:`Milestones`, :guilabel:`Deadline`, :guilabel:`Timesheets`, :guilabel:`Chatter`,
+  :guilabel:`Activities`: those fields are not copied;
+- :guilabel:`Subtasks`: copied from the original task, which becomes a parent of all the tasks in
+  recurrence;
+- A **smart button** on the task displays the total number of existing recurrences.
+
+.. tip::
+   To see the task in your project dashboard before the scheduled date, consider setting up the
+   recurrence date to a day earlier.
+
+Edit or stop task recurrence
+----------------------------
+
+**To edit** the recurrence, open the task: a blue banner invites you to choose whether you wish to
+apply your changes to this task only or to a sequence of tasks.
+
+**To stop** the recurrence, open the task, then go to the :guilabel:`Recurrency` tab and uncheck
+:guilabel:`Recurrent`.