[ADD] bus_alt_connection

bus_alt_connection/README.rst

@@ -0,0 +1,187 @@
+==================
+Bus Alt Connection
+==================
+
+.. !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+   !! This file is generated by oca-gen-addon-readme !!
+   !! changes will be overwritten.                   !!
+   !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+.. |badge1| image:: https://img.shields.io/badge/maturity-Beta-yellow.png
+    :target: https://odoo-community.org/page/development-status
+    :alt: Beta
+.. |badge2| image:: https://img.shields.io/badge/licence-AGPL--3-blue.png
+    :target: http://www.gnu.org/licenses/agpl-3.0-standalone.html
+    :alt: License: AGPL-3
+.. |badge3| image:: https://img.shields.io/badge/github-OCA%2Fserver--tools-lightgray.png?logo=github
+    :target: https://github.com/OCA/server-tools/tree/12.0/bus_alt_connection
+    :alt: OCA/server-tools
+.. |badge4| image:: https://img.shields.io/badge/weblate-Translate%20me-F47D42.png
+    :target: https://translation.odoo-community.org/projects/server-tools-12-0/server-tools-12-0-bus_alt_connection
+    :alt: Translate me on Weblate
+.. |badge5| image:: https://img.shields.io/badge/runbot-Try%20me-875A7B.png
+    :target: https://runbot.odoo-community.org/runbot/149/12.0
+    :alt: Try me on Runbot
+
+|badge1| |badge2| |badge3| |badge4| |badge5| 
+
+This module makes it possible to use PgBouncer_ as a connection pooler
+for odoo.
+
+.. _PgBouncer: https://pgbouncer.github.io/
+
+Why isn't odoo's connection pooling good enough?
+================================================
+
+Odoo's builtin connection pooling works at process level: each Odoo process
+has its own ConnectionPool_, limited to ``db_maxconn``.
+
+It does the job of re-using open connections available in the pool.
+But it never closes these connections, `unless reaching db_maxconn`_.
+
+.. _ConnectionPool: https://github.com/odoo/odoo/blob/12.0/odoo/sql_db.py#L525
+.. _`unless reaching db_maxconn`: https://github.com/odoo/odoo/blob/12.0/odoo/sql_db.py#L593
+
+In practice, we observe that each odoo worker will end up
+with up to 3 open connection in its pool.
+With 10 http workers, that's up to 30 connection continuously open just
+for one single instance.
+
+Here comes PgBouncer
+====================
+
+PgBouncer will help to limit this number of open connections,
+by sharing a pool of connections at the instance level, between
+all workers. Odoo workers will still have up to 3 open connections,
+but these will be connections to PgBouncer, that on its side will
+close unnecessary connections to pg.
+
+This has proven to help performances on Odoo deployments with
+multiple instances.
+
+It allows you to define how resources should be shared,
+according to your priorities, e.g. :
+
+* key odoo instance on host A can open up to 30 connections
+* while odoo instance on host B, dedicated to reports,
+  can open up to 10 connections only
+
+And most importantly, it helps you to ensure that
+``max_connections`` will never be reached on pg server side.
+
+
+Why is this module needed?
+==========================
+
+When configuring PgBouncer, you can choose between 2 transaction pooling modes:
+
+* `pool_mode = session`
+* `pool_mode = transaction`
+
+If we choose `pool_mode = session`, then one server connection will be tied
+to a given odoo process until its death, which is exactly what we're trying
+to change. Thus, to release the server connection once the transaction is
+complete, we use `pool_mode = transaction`.
+
+This works fine, except for Odoo's longpolling features that relies
+on the `LISTEN/NOTIFY`_ mechanism from pg, which is `not compatible`_ with that
+mode.
+
+.. _`LISTEN/NOTIFY`: https://www.postgresql.org/docs/9.6/static/sql-notify.html
+.. _`not compatible`: https://wiki.postgresql.org/wiki/PgBouncer
+
+
+To be more precise, `NOTIFY` statements are properly transfered by PgBouncer
+in that mode; only the `LISTEN` statement isn't (because it needs to keep the
+server connection open).
+
+So for the unique "listening" connection per instance that requires this
+statement (here_), we need odoo to connect directly to the pg server, bypassing
+PgBouncer.
+
+That's what this module implements, by overriding the relevant method
+of the Dispatcher_.
+
+.. _here: https://github.com/odoo/odoo/blob/12.0/addons/bus/models/bus.py#L166
+.. _Dispatcher: https://github.com/odoo/odoo/blob/12.0/addons/bus/models/bus.py#L105
+
+**Table of contents**
+
+.. contents::
+   :local:
+
+Installation
+============
+
+You don't need to install this module in the database(s) to enable it.
+
+But you need to load it server-wide:
+
+* By starting Odoo with ``--load=web,bus_alt_connection``
+
+* Or by updating its configuration file:
+
+.. code-block:: ini
+
+  [options]
+  (...)
+  server_wide_modules = web,bus_alt_connection
+
+Configuration
+=============
+
+You need to define how to connect directly to the database:
+
+* Either by defining environment variables:
+
+    - ``IMDISPATCHER_DB_HOST=db-01``
+    - ``IMDISPATCHER_DB_PORT=5432``
+
+* Or in Odoo's configuration file:
+
+.. code-block:: ini
+
+  [options]
+  (...)
+  imdispatcher_db_host = db-01
+  imdispatcher_db_port = 5432
+
+Bug Tracker
+===========
+
+Bugs are tracked on `GitHub Issues <https://github.com/OCA/server-tools/issues>`_.
+In case of trouble, please check there if your issue has already been reported.
+If you spotted it first, help us smashing it by providing a detailed and welcomed
+`feedback <https://github.com/OCA/server-tools/issues/new?body=module:%20bus_alt_connection%0Aversion:%2012.0%0A%0A**Steps%20to%20reproduce**%0A-%20...%0A%0A**Current%20behavior**%0A%0A**Expected%20behavior**>`_.
+
+Do not contact contributors directly about support or help with technical issues.
+
+Credits
+=======
+
+Authors
+~~~~~~~
+
+* Trobz
+
+Contributors
+~~~~~~~~~~~~
+
+* Nils Hamerlinck <nils@trobz.com>
+
+Maintainers
+~~~~~~~~~~~
+
+This module is maintained by the OCA.
+
+.. image:: https://odoo-community.org/logo.png
+   :alt: Odoo Community Association
+   :target: https://odoo-community.org
+
+OCA, or the Odoo Community Association, is a nonprofit organization whose
+mission is to support the collaborative development of Odoo features and
+promote its widespread use.
+
+This module is part of the `OCA/server-tools <https://github.com/OCA/server-tools/tree/12.0/bus_alt_connection>`_ project on GitHub.
+
+You are welcome to contribute. To learn how please visit https://odoo-community.org/page/Contribute.

bus_alt_connection/__init__.py

@@ -0,0 +1,3 @@
+# Copyright 2019 Trobz <https://trobz.com>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+from . import models

bus_alt_connection/__manifest__.py

@@ -0,0 +1,15 @@
+# Copyright 2019 Trobz <https://trobz.com>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+
+{
+    'name': 'Bus Alt Connection',
+    'summary': 'Needed when using PgBouncer as a connection pooler',
+    'version': '12.0.1.0.0',
+    'author': 'Trobz,Odoo Community Association (OCA)',
+    'website': 'https://github.com/OCA/server-tools',
+    'category': 'Extra Tools',
+    'license': 'AGPL-3',
+    'depends': ['bus'],
+    'installable': True,
+    'auto_install': False,
+}

bus_alt_connection/models/__init__.py

@@ -0,0 +1,3 @@
+# Copyright 2019 Trobz <https://trobz.com>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+from . import bus

bus_alt_connection/models/bus.py

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+# Copyright 2019 Trobz <https://trobz.com>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+
+import os
+import json
+import logging
+import select
+
+import psycopg2
+from psycopg2.extensions import ISOLATION_LEVEL_AUTOCOMMIT
+
+import odoo
+from odoo.tools import config
+
+from odoo.addons.bus.models.bus import hashable, TIMEOUT
+import odoo.addons.bus.models.bus
+
+
+_logger = logging.getLogger(__name__)
+
+
+def _connection_info_for(db_name):
+    db_or_uri, connection_info = odoo.sql_db.connection_info_for(db_name)
+
+    for p in ('host', 'port'):
+        cfg = (os.environ.get('ODOO_IMDISPATCHER_DB_%s' % p.upper()) or
+               config.get('imdispatcher_db_' + p))
+
+        if cfg:
+            connection_info[p] = cfg
+
+    return connection_info
+
+
+class ImDispatch(odoo.addons.bus.models.bus.ImDispatch):
+
+    def loop(self):
+        """ Dispatch postgres notifications to the relevant
+            polling threads/greenlets """
+        connection_info = _connection_info_for('postgres')
+        _logger.info("Bus.loop listen imbus on db postgres "
+                     "(via %(host)s:%(port)s)",
+                     connection_info)
+        conn = psycopg2.connect(**connection_info)
+        conn.set_isolation_level(ISOLATION_LEVEL_AUTOCOMMIT)
+        with conn.cursor() as cr:
+            cr.execute("listen imbus")
+            conn.commit()
+            while True:
+                if select.select([conn], [], [], TIMEOUT) == ([], [], []):
+                    pass
+                else:
+                    conn.poll()
+                    channels = []
+                    while conn.notifies:
+                        channels.extend(json.loads(conn
+                                                   .notifies.pop().payload))
+                    # dispatch to local threads/greenlets
+                    events = set()
+                    for channel in channels:
+                        events.update(self.channels.pop(hashable(channel),
+                                                        set()))
+                    for event in events:
+                        event.set()
+
+
+odoo.addons.bus.models.bus.ImDispatch = ImDispatch
+
+# we can replace the existing dispatcher because its thread
+# has not been started yet; indeed, since a2ed3d it only starts
+# on first /poll request:
+# https://github.com/odoo/odoo/commit/a2ed3d3d5bdb6025a1ba14ad557a115a86413e65
+
+if not odoo.multi_process or odoo.evented:
+    dispatch = ImDispatch()
+    odoo.addons.bus.models.bus.dispatch = dispatch
+    odoo.addons.bus.controllers.main.dispatch = dispatch

bus_alt_connection/readme/CONFIGURE.rst

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+You need to define how to connect directly to the database:
+
+* Either by defining environment variables:
+
+    - ``IMDISPATCHER_DB_HOST=db-01``
+    - ``IMDISPATCHER_DB_PORT=5432``
+
+* Or in Odoo's configuration file:
+
+.. code-block:: ini
+
+  [options]
+  (...)
+  imdispatcher_db_host = db-01
+  imdispatcher_db_port = 5432

bus_alt_connection/readme/CONTRIBUTORS.rst

@@ -0,0 +1 @@
+* Nils Hamerlinck <nils@trobz.com>

bus_alt_connection/readme/DESCRIPTION.rst

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+This module makes it possible to use PgBouncer_ as a connection pooler
+for odoo.
+
+.. _PgBouncer: https://pgbouncer.github.io/
+
+Why isn't odoo's connection pooling good enough?
+================================================
+
+Odoo's builtin connection pooling works at process level: each Odoo process
+has its own ConnectionPool_, limited to ``db_maxconn``.
+
+It does the job of re-using open connections available in the pool.
+But it never closes these connections, `unless reaching db_maxconn`_.
+
+.. _ConnectionPool: https://github.com/odoo/odoo/blob/12.0/odoo/sql_db.py#L525
+.. _`unless reaching db_maxconn`: https://github.com/odoo/odoo/blob/12.0/odoo/sql_db.py#L593
+
+In practice, we observe that each odoo worker will end up
+with up to 3 open connection in its pool.
+With 10 http workers, that's up to 30 connection continuously open just
+for one single instance.
+
+Here comes PgBouncer
+====================
+
+PgBouncer will help to limit this number of open connections,
+by sharing a pool of connections at the instance level, between
+all workers. Odoo workers will still have up to 3 open connections,
+but these will be connections to PgBouncer, that on its side will
+close unnecessary connections to pg.
+
+This has proven to help performances on Odoo deployments with
+multiple instances.
+
+It allows you to define how resources should be shared,
+according to your priorities, e.g. :
+
+* key odoo instance on host A can open up to 30 connections
+* while odoo instance on host B, dedicated to reports,
+  can open up to 10 connections only
+
+And most importantly, it helps you to ensure that
+``max_connections`` will never be reached on pg server side.
+
+
+Why is this module needed?
+==========================
+
+When configuring PgBouncer, you can choose between 2 transaction pooling modes:
+
+* `pool_mode = session`
+* `pool_mode = transaction`
+
+If we choose `pool_mode = session`, then one server connection will be tied
+to a given odoo process until its death, which is exactly what we're trying
+to change. Thus, to release the server connection once the transaction is
+complete, we use `pool_mode = transaction`.
+
+This works fine, except for Odoo's longpolling features that relies
+on the `LISTEN/NOTIFY`_ mechanism from pg, which is `not compatible`_ with that
+mode.
+
+.. _`LISTEN/NOTIFY`: https://www.postgresql.org/docs/9.6/static/sql-notify.html
+.. _`not compatible`: https://wiki.postgresql.org/wiki/PgBouncer
+
+
+To be more precise, `NOTIFY` statements are properly transfered by PgBouncer
+in that mode; only the `LISTEN` statement isn't (because it needs to keep the
+server connection open).
+
+So for the unique "listening" connection per instance that requires this
+statement (here_), we need odoo to connect directly to the pg server, bypassing
+PgBouncer.
+
+That's what this module implements, by overriding the relevant method
+of the Dispatcher_.
+
+.. _here: https://github.com/odoo/odoo/blob/12.0/addons/bus/models/bus.py#L166
+.. _Dispatcher: https://github.com/odoo/odoo/blob/12.0/addons/bus/models/bus.py#L105

bus_alt_connection/readme/INSTALL.rst

@@ -0,0 +1,13 @@
+You don't need to install this module in the database(s) to enable it.
+
+But you need to load it server-wide:
+
+* By starting Odoo with ``--load=web,bus_alt_connection``
+
+* Or by updating its configuration file:
+
+.. code-block:: ini
+
+  [options]
+  (...)
+  server_wide_modules = web,bus_alt_connection

bus_alt_connection/static/description/index.html

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+  margin-top: 0.5em ;
+  margin-bottom: 0.5em }
+
+table.footnote {
+  border-left: solid 1px black;
+  margin-left: 1px }
+
+table.docutils td, table.docutils th,
+table.docinfo td, table.docinfo th {
+  padding-left: 0.5em ;
+  padding-right: 0.5em ;
+  vertical-align: top }
+
+table.docutils th.field-name, table.docinfo th.docinfo-name {
+  font-weight: bold ;
+  text-align: left ;
+  white-space: nowrap ;
+  padding-left: 0 }
+
+/* "booktabs" style (no vertical lines) */
+table.docutils.booktabs {
+  border: 0px;
+  border-top: 2px solid;
+  border-bottom: 2px solid;
+  border-collapse: collapse;
+}
+table.docutils.booktabs * {
+  border: 0px;
+}
+table.docutils.booktabs th {
+  border-bottom: thin solid;
+  text-align: left;
+}
+
+h1 tt.docutils, h2 tt.docutils, h3 tt.docutils,
+h4 tt.docutils, h5 tt.docutils, h6 tt.docutils {
+  font-size: 100% }
+
+ul.auto-toc {
+  list-style-type: none }
+
+</style>
+</head>
+<body>
+<div class="document" id="bus-alt-connection">
+<h1 class="title">Bus Alt Connection</h1>
+
+<!-- !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+!! This file is generated by oca-gen-addon-readme !!
+!! changes will be overwritten.                   !!
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! -->
+<p><a class="reference external" href="https://odoo-community.org/page/development-status"><img alt="Beta" src="https://img.shields.io/badge/maturity-Beta-yellow.png" /></a> <a class="reference external" href="http://www.gnu.org/licenses/agpl-3.0-standalone.html"><img alt="License: AGPL-3" src="https://img.shields.io/badge/licence-AGPL--3-blue.png" /></a> <a class="reference external" href="https://github.com/OCA/server-tools/tree/12.0/bus_alt_connection"><img alt="OCA/server-tools" src="https://img.shields.io/badge/github-OCA%2Fserver--tools-lightgray.png?logo=github" /></a> <a class="reference external" href="https://translation.odoo-community.org/projects/server-tools-12-0/server-tools-12-0-bus_alt_connection"><img alt="Translate me on Weblate" src="https://img.shields.io/badge/weblate-Translate%20me-F47D42.png" /></a> <a class="reference external" href="https://runbot.odoo-community.org/runbot/149/12.0"><img alt="Try me on Runbot" src="https://img.shields.io/badge/runbot-Try%20me-875A7B.png" /></a></p>
+<p>This module makes it possible to use <a class="reference external" href="https://pgbouncer.github.io/">PgBouncer</a> as a connection pooler
+for odoo.</p>
+<div class="section" id="why-isn-t-odoo-s-connection-pooling-good-enough">
+<h1>Why isn’t odoo’s connection pooling good enough?</h1>
+<p>Odoo’s builtin connection pooling works at process level: each Odoo process
+has its own <a class="reference external" href="https://github.com/odoo/odoo/blob/12.0/odoo/sql_db.py#L525">ConnectionPool</a>, limited to <tt class="docutils literal">db_maxconn</tt>.</p>
+<p>It does the job of re-using open connections available in the pool.
+But it never closes these connections, <a class="reference external" href="https://github.com/odoo/odoo/blob/12.0/odoo/sql_db.py#L593">unless reaching db_maxconn</a>.</p>
+<p>In practice, we observe that each odoo worker will end up
+with up to 3 open connection in its pool.
+With 10 http workers, that’s up to 30 connection continuously open just
+for one single instance.</p>
+</div>
+<div class="section" id="here-comes-pgbouncer">
+<h1>Here comes PgBouncer</h1>
+<p>PgBouncer will help to limit this number of open connections,
+by sharing a pool of connections at the instance level, between
+all workers. Odoo workers will still have up to 3 open connections,
+but these will be connections to PgBouncer, that on its side will
+close unnecessary connections to pg.</p>
+<p>This has proven to help performances on Odoo deployments with
+multiple instances.</p>
+<p>It allows you to define how resources should be shared,
+according to your priorities, e.g. :</p>
+<ul class="simple">
+<li>key odoo instance on host A can open up to 30 connections</li>
+<li>while odoo instance on host B, dedicated to reports,
+can open up to 10 connections only</li>
+</ul>
+<p>And most importantly, it helps you to ensure that
+<tt class="docutils literal">max_connections</tt> will never be reached on pg server side.</p>
+</div>
+<div class="section" id="why-is-this-module-needed">
+<h1>Why is this module needed?</h1>
+<p>When configuring PgBouncer, you can choose between 2 transaction pooling modes:</p>
+<ul class="simple">
+<li><cite>pool_mode = session</cite></li>
+<li><cite>pool_mode = transaction</cite></li>
+</ul>
+<p>If we choose <cite>pool_mode = session</cite>, then one server connection will be tied
+to a given odoo process until its death, which is exactly what we’re trying
+to change. Thus, to release the server connection once the transaction is
+complete, we use <cite>pool_mode = transaction</cite>.</p>
+<p>This works fine, except for Odoo’s longpolling features that relies
+on the <a class="reference external" href="https://www.postgresql.org/docs/9.6/static/sql-notify.html">LISTEN/NOTIFY</a> mechanism from pg, which is <a class="reference external" href="https://wiki.postgresql.org/wiki/PgBouncer">not compatible</a> with that
+mode.</p>
+<p>To be more precise, <cite>NOTIFY</cite> statements are properly transfered by PgBouncer
+in that mode; only the <cite>LISTEN</cite> statement isn’t (because it needs to keep the
+server connection open).</p>
+<p>So for the unique “listening” connection per instance that requires this
+statement (<a class="reference external" href="https://github.com/odoo/odoo/blob/12.0/addons/bus/models/bus.py#L166">here</a>), we need odoo to connect directly to the pg server, bypassing
+PgBouncer.</p>
+<p>That’s what this module implements, by overriding the relevant method
+of the <a class="reference external" href="https://github.com/odoo/odoo/blob/12.0/addons/bus/models/bus.py#L105">Dispatcher</a>.</p>
+<p><strong>Table of contents</strong></p>
+</div>
+<div class="section" id="installation">
+<h1>Installation</h1>
+<p>You don’t need to install this module in the database(s) to enable it.</p>
+<p>But you need to load it server-wide:</p>
+<ul class="simple">
+<li>By starting Odoo with <tt class="docutils literal"><span class="pre">--load=web,bus_alt_connection</span></tt></li>
+<li>Or by updating its configuration file:</li>
+</ul>
+<pre class="code ini literal-block">
+<span class="k">[options]</span>
+<span class="na">(...)</span>
+<span class="na">server_wide_modules</span> <span class="o">=</span> <span class="s">web,bus_alt_connection</span>
+</pre>
+</div>
+<div class="section" id="configuration">
+<h1>Configuration</h1>
+<p>You need to define how to connect directly to the database:</p>
+<ul>
+<li><p class="first">Either by defining environment variables:</p>
+<blockquote>
+<ul class="simple">
+<li><tt class="docutils literal"><span class="pre">IMDISPATCHER_DB_HOST=db-01</span></tt></li>
+<li><tt class="docutils literal">IMDISPATCHER_DB_PORT=5432</tt></li>
+</ul>
+</blockquote>
+</li>
+<li><p class="first">Or in Odoo’s configuration file:</p>
+</li>
+</ul>
+<pre class="code ini literal-block">
+<span class="k">[options]</span>
+<span class="na">(...)</span>
+<span class="na">imdispatcher_db_host</span> <span class="o">=</span> <span class="s">db-01</span>
+<span class="na">imdispatcher_db_port</span> <span class="o">=</span> <span class="s">5432</span>
+</pre>
+</div>
+<div class="section" id="bug-tracker">
+<h1>Bug Tracker</h1>
+<p>Bugs are tracked on <a class="reference external" href="https://github.com/OCA/server-tools/issues">GitHub Issues</a>.
+In case of trouble, please check there if your issue has already been reported.
+If you spotted it first, help us smashing it by providing a detailed and welcomed
+<a class="reference external" href="https://github.com/OCA/server-tools/issues/new?body=module:%20bus_alt_connection%0Aversion:%2012.0%0A%0A**Steps%20to%20reproduce**%0A-%20...%0A%0A**Current%20behavior**%0A%0A**Expected%20behavior**">feedback</a>.</p>
+<p>Do not contact contributors directly about support or help with technical issues.</p>
+</div>
+<div class="section" id="credits">
+<h1>Credits</h1>
+<div class="section" id="authors">
+<h2>Authors</h2>
+<ul class="simple">
+<li>Trobz</li>
+</ul>
+</div>
+<div class="section" id="contributors">
+<h2>Contributors</h2>
+<ul class="simple">
+<li>Nils Hamerlinck &lt;<a class="reference external" href="mailto:nils&#64;trobz.com">nils&#64;trobz.com</a>&gt;</li>
+</ul>
+</div>
+<div class="section" id="maintainers">
+<h2>Maintainers</h2>
+<p>This module is maintained by the OCA.</p>
+<a class="reference external image-reference" href="https://odoo-community.org"><img alt="Odoo Community Association" src="https://odoo-community.org/logo.png" /></a>
+<p>OCA, or the Odoo Community Association, is a nonprofit organization whose
+mission is to support the collaborative development of Odoo features and
+promote its widespread use.</p>
+<p>This module is part of the <a class="reference external" href="https://github.com/OCA/server-tools/tree/12.0/bus_alt_connection">OCA/server-tools</a> project on GitHub.</p>
+<p>You are welcome to contribute. To learn how please visit <a class="reference external" href="https://odoo-community.org/page/Contribute">https://odoo-community.org/page/Contribute</a>.</p>
+</div>
+</div>
+</div>
+</body>
+</html>