Module structure¶

A module can contain the following elements:

Business object : declared as Python classes extending the class osv.Model, the persistence of these resource is completly managed by OpenERP’s ORM.

Data : XML/CSV files with meta-data (views and workflows declaration), configuration data (modules parametrization) and demo data (optional but recommended for testing),

Reports : RML (XML format). HTML/MAKO or OpenOffice report templates, to be merged with any kind of business data, and generate HTML, ODT or PDF reports.

Module composition

Each module is contained in its own directory within either the server/bin/addons directory or another directory of addons, configured in server installation. To create a new module for example the ‘OpenAcademy’ module, the following steps are required:

create a openacademy subdirectory in the source/addons directory

create the module import file __init__.py

create the module manifield file __openerp__.py

create Python files containing objects

create .xml files holding module data such as views, menu entries or demo data

optionally create reports or workflows

Python import file init.py¶

The __init__.py file is the Python import file, because an OpenERP module is also a regular Python module. The file should import all the other python file or submodules.

For example, if a module contains a single python file named openacademy.py, the file should look like:

import openacademy

Manifest file openerp.py¶

In the created module directory, you must add a __openerp__.py file. This file, which must be a Python dict literal, is responsible to

determine the XML files that will be parsed during the initialization of the server, and also to

determine the dependencies of the created module.

declare additional meta data

This file must contain a Python dictionary with the following values:

name             The name of the module in English.
version          The version of the module.
summary          Short description or keywords
description      The module description (text).
category         The categrory of the module
author           The author of the module.
website          URL of the website of the module.
license          The license of the module (default: AGPL-3).
depends          List of modules on which this module depends beside base.
data             List of .xml files to load when the module is installed or updated.
demo             List of additional .xml files to load when the module is
                 installed or updated and demo flag is active.
installable      True or False. Determines whether the module is installable
                 or not.
auto_install     True or False (default: False). If set to ``True``, the
                 module is a link module. It will be installed as soon
                 as all its dependencies are installed.

For the openacademy module, here is an example of __openerp__.py declaration file:

{
    'name' : "OpenAcademy",
    'version' : "1.0",
    'author' : "OpenERP SA",
    'category' : "Tools",
    'depends' : ['mail'],
    'data' : [
        'openacademy_view.xml',
        'openacademy_data.xml',
        'report/module_report.xml',
        'wizard/module_wizard.xml',
    ],
    'demo' : [
        'openacademy_demo.xml'
    ],
    'installable': True,
}

Objects¶

All OpenERP resources are objects: invoices, partners. Metadata are also object too: menus, actions, reports... Object names are hierarchical, as in the following examples:

account.transfer : a money transfer

account.invoice : an invoice

account.invoice.line : an invoice line

Generally, the first word is the name of the module: account, stock, sale.

Those object are declared in python be subclassing osv.Model

The ORM of OpenERP is constructed over PostgreSQL. It is thus possible to query the object used by OpenERP using the object interface (ORM) or by directly using SQL statements.

But it is dangerous to write or read directly in the PostgreSQL database, as you will shortcut important steps like constraints checking or workflow modification.

XML Files¶

XML files located in the module directory are used to initialize or update the the database when the module is installed or updated. They are used for many purposes, among which we can cite :

initialization and demonstration data declaration,

views declaration,

reports declaration,

workflows declaration.

General structure of OpenERP XML files is more detailed in the xml-serialization section. Look here if you are interested in learning more about initialization and demonstration data declaration XML files. The following section are only related to XML specific to actions, menu entries, reports, wizards and workflows declaration.

Data can be inserted or updated into the PostgreSQL tables corresponding to the OpenERP objects using XML files. The general structure of an OpenERP XML file is as follows:

<?xml version="1.0"?>
<openerp>
  <data>
    <record model="model.name_1" id="id_name_1">
      <field name="field1"> "field1 content" </field>
      <field name="field2"> "field2 content" </field>
      (...)
    </record>
    <record model="model.name_2" id="id_name_2">
        (...)
    </record>
    (...)
  </data>
</openerp>

Record Tag¶

Description

The addition of new data is made with the record tag. This one takes a mandatory attribute : model. Model is the object name where the insertion has to be done. The tag record can also take an optional attribute: id. If this attribute is given, a variable of this name can be used later on, in the same file, to make reference to the newly created resource ID.

A record tag may contain field tags. They indicate the record’s fields value. If a field is not specified the default value will be used.

The Record Field tag¶

The attributes for the field tag are the following:

name : mandatory: the field name
eval : optional: python expression that indicating the value to add
ref: reference to an id defined in this file
model: model to be looked up in the search
search: a query

Example

<record model="ir.actions.report.xml" id="l0">
     <field name="model">account.invoice</field>
     <field name="name">Invoices List</field>
     <field name="report_name">account.invoice.list</field>
     <field name="report_xsl">account/report/invoice.xsl</field>
     <field name="report_xml">account/report/invoice.xml</field>
</record>

Let’s review an example taken from the OpenERP source (base_demo.xml in the base module):

<record model="res.company" id="main_company">
    <field name="name">Tiny sprl</field>
    <field name="partner_id" ref="main_partner"/>
    <field name="currency_id" ref="EUR"/>
</record>

<record model="res.users" id="user_admin">
    <field name="login">admin</field>
    <field name="password">admin</field>
    <field name="name">Administrator</field>
    <field name="signature">Administrator</field>
    <field name="action_id" ref="action_menu_admin"/>
    <field name="menu_id" ref="action_menu_admin"/>
    <field name="address_id" ref="main_address"/>
    <field name="groups_id" eval="[(6,0,[group_admin])]"/>
    <field name="company_id" ref="main_company"/>
</record>

This last record defines the admin user :

The fields login, password, etc are straightforward.

The ref attribute allows to fill relations between the records :

<field name="company_id" ref="main_company"/>

The field company_id is a many-to-one relation from the user object to the company object, and main_company is the id of to associate.

The eval attribute allows to put some python code in the xml: here the groups_id field is a many2many. For such a field, “[(6,0,[group_admin])]” means : Remove all the groups associated with the current user and use the list [group_admin] as the new associated groups (and group_admin is the id of another record).

The search attribute allows to find the record to associate when you do not know its xml id. You can thus specify a search criteria to find the wanted record. The criteria is a list of tuples of the same form than for the predefined search method. If there are several results, an arbitrary one will be chosen (the first one):

<field name="partner_id" search="[]" model="res.partner"/>

This is a classical example of the use of search in demo data: here we do not really care about which partner we want to use for the test, so we give an empty list. Notice the model attribute is currently mandatory.

Function tag¶

A function tag can contain other function tags.

model : mandatory: The model to be used
name : mandatory: the function given name
eval: should evaluate to the list of parameters of the method to be called, excluding cr and uid

Example

<function model="ir.ui.menu" name="search" eval="[[('name','=','Operations')]]"/>

Views¶

Views are a way to represent the objects on the client side. They indicate to the client how to lay out the data coming from the objects on the screen.

There are two types of views:

form views

tree views

Lists are simply a particular case of tree views.

A same object may have several views: the first defined view of a kind (tree, form, ...) will be used as the default view for this kind. That way you can have a default tree view (that will act as the view of a one2many) and a specialized view with more or less information that will appear when one double-clicks on a menu item. For example, the products have several views according to the product variants.

Views are described in XML.

If no view has been defined for an object, the object is able to generate a view to represent itself. This can limit the developer’s work but results in less ergonomic views.

Usage example¶

When you open an invoice, here is the chain of operations followed by the client:

An action asks to open the invoice (it gives the object’s data (account.invoice), the view, the domain (e.g. only unpaid invoices) ).

The client asks (with XML-RPC) to the server what views are defined for the invoice object and what are the data it must show.

The client displays the form according to the view

To develop new objects¶

The design of new objects is restricted to the minimum: create the objects and optionally create the views to represent them. The PostgreSQL tables do not have to be written by hand because the objects are able to automatically create them (or adapt them in case they already exist).

Reports¶

OpenERP uses a flexible and powerful reporting system. Reports are generated either in PDF or in HTML. Reports are designed on the principle of separation between the data layer and the presentation layer.

Reports are described more in details in the Reporting chapter.

Workflow¶

The objects and the views allow you to define new forms very simply, lists/trees and interactions between them. But that is not enough, you must define the dynamics of these objects.

A few examples:

a confirmed sale order must generate an invoice, according to certain conditions

a paid invoice must, only under certain conditions, start the shipping order

The workflows describe these interactions with graphs. One or several workflows may be associated to the objects. Workflows are not mandatory; some objects don’t have workflows.

Below is an example workflow used for sale orders. It must generate invoices and shipments according to certain conditions.

In this graph, the nodes represent the actions to be done:

create an invoice,

cancel the sale order,

generate the shipping order, ...

The arrows are the conditions;

waiting for the order validation,

invoice paid,

click on the cancel button, ...

The squared nodes represent other Workflows;

the invoice

the shipping

i18n¶

Changed in version 5.0.

Each module has its own i18n folder. In addition, OpenERP can now deal with .po [1] files as import/export format. The translation files of the installed languages are automatically loaded when installing or updating a module.

Translations are managed by the Launchpad Web interface. Here, you’ll find the list of translatable projects.

Please read the FAQ before asking questions.

[1]	http://www.gnu.org/software/autoconf/manual/gettext/PO-Files.html#PO-Files

Module structure¶

Python import file init.py¶

Manifest file openerp.py¶

Objects¶

XML Files¶

Record Tag¶

The Record Field tag¶

Function tag¶

Views¶

Usage example¶

To develop new objects¶

Reports¶

Workflow¶

i18n¶

Table Of Contents

Related Topics

This Page

Module structure¶

Python import file __init__.py¶

Manifest file __openerp__.py¶

Objects¶

XML Files¶

Record Tag¶

The Record Field tag¶

Function tag¶

Views¶

Usage example¶

To develop new objects¶

Reports¶

Workflow¶

i18n¶

Python import file init.py¶

Manifest file openerp.py¶