There are lots of ways to set up an Odoo development environment. This chapter proposes one of them; you will certainly find a number of other tutorials on the web explaining other approaches. Keep in mind that this chapter is about a development environment that has different requirements from a production environment. This will be covered in Chapter 3, Server Deployment.

If you are new to Odoo development, you must know about certain aspects of the Odoo ecosystem. The next section will give you a brief introduction to those aspects, and then we will move on to the installation of Odoo for development.

Odoo provides the developer with out-of-the-box modularity. Its powerful framework helps the developer to build projects very quickly. There are various characters in the Odoo ecosystem that you should be familiar with before starting your journey of becoming a successful Odoo developer.

Odoo comes with two editions. The first is the Community Edition, which is open source, and the second is the Enterprise Edition, which has licensing fees. Unlike other software vendors, Odoo Enterprise Edition is just a bunch of advance applications that adds extra features/apps in the Community Edition. Basically, Enterprise Edition runs on top of the Community Edition. The Community Edition comes under the Lesser General Public License v3.0 (LGPLv3) license and comes with all of the basic Enterprise resource planning (ERP) applications, such as sale, Customer Relationship Management (CRM), invoicing, purchase, website builder, and so on. Alternatively, Enterprise Edition comes with the Odoo Enterprise Edition License, which is a proprietary license. Odoo Enterprise Edition comes with advanced features such as full accounting, studio, Voice over Internet Protocol (VoIP), mobile responsive design, e-sign, marketing automation, and delivery and banking integrations. Enterprise Edition also provides you with unlimited bugfixes. The following diagram shows that Enterprise Edition depends on the Community Edition, which is why you need Community Edition to use Enterprise Edition:

You can see a full comparison of both editions here: https://www.odoo.com/page/editions.

The whole code base of Odoo is hosted on GitHub. You can post bugs/issues for stable versions here. You can also propose a new feature by submitting Pull Requests (PR). There are several repositories in Odoo; see the following table for more information:

Every year, Odoo releases one major (Long Term Support (LTS)) version and a few minor versions. Minor versions are mostly used in Odoo's online SaaS service, meaning that Odoo SaaS users get early access to these features. Major version branches have names such as 12.0, 11.0, and 10.0, while minor version branches have names such as saas-12.1, saas-11.1, and saas-11.2 on GitHub. The master branch is under development and is subject to change at any time. Consequently, it is advisable not to use this for production, since it might break down your database.

Runbot is Odoo's automated testing environment. This pulls the latest branches from Odoo's Git repositories and creates the builds for the last four commits. Here, you can test all stable and in-development branches. You can even play with the Enterprise Edition and its development branches.

Every build has a different background color, which indicates the status of the test cases. A green background color means that all of the test cases run successfully and you can test that branch, while a red background color means that some test cases have failed on this branch and some features might be broken on that build. You can view the logs for all test cases, which show exactly what happens during installation. Every build has two databases. The all database has all of the modules installed on it, while the base database only has base Odoo modules installed. Every build is installed with basic demo data, and therefore you can test it quickly without extra configurations.

The following credentials can be used to access any runbot build:

• Login ID: admin Password: admin
• Login ID:demo Password: demo
• Login ID: portal Password: portal

Odoo launched the app store a few years back, and this was an instant success. Right now, there are over 15,000 different apps hosted there. In the app store, you will find lots of free and paid applications for different versions. This includes specific solutions for different business verticals, such as education, food industries, and medicine. It also includes apps that extend/add new features to existing Odoo applications. The app store also provides numerous beautiful themes for the Odoo website builder. In Chapter 4, Creating Odoo Add-On Modules, we will look at how you can set pricing and currency for your custom module.

You can access the Odoo app store via the following URL: https://www.odoo.com/apps.

Odoo Community Association (OCA) is a non-profit organization that develops/manages community-based Odoo modules. All OCA modules are open source and maintained by Odoo community members. Under the OCA's GitHub account, you will find multiple repositories for different Odoo applications. Apart from Odoo modules, it also contains various tools, a migration library, accounting localizations, and so on.

Here is the URL for OCA's official GitHub account: https://github.com/OCA.

Odoo has a very powerful framework, and tons of things can be achieved just by using/activating options or by following specific patterns. Consequently, if you run into some technical issues or if you are not sure about some complex cases, then you can post your query on Odoo's official help forum. Lots of developers are active on this forum, including some official Odoo employees.

You can search for or post your questions at the following URL: https://help.odoo.com.

For Odoo deployment, it is recommended to use a GNU/Linux environment. You may be more at ease using Microsoft Windows or Mac OS X, but the fact is that most Odoo developers use GNU/Linux, and you are much more likely to get support from the community for OS-level issues that occur on GNU/Linux than on Windows.

It is also recommended to develop using the same environment (the same distribution and the same version) as the one that will be used in production. This will avoid nasty surprises, such as discovering on the day of deployment that a library has a different version than expected with slightly different and incompatible behavior. If your workstation is using a different OS, a good approach is to set up a Virtual Machine (VM) on your workstation and install a GNU/Linux distribution in the VM.

This book assumes that you are running Debian GNU/Linux as its stable version (this is version 9, code name Stretch, at the time of writing). Ubuntu is another popular choice, and since it is built on top of Debian, most of the examples in this book should work without needing to be changed. Whatever Linux distribution you choose, you should have some notion of how to use it from the command line, and having knowledge about system administration will certainly not cause any harm.

We are assuming that you have Linux up and running and that you have an account with root access, either because you know the root password, or because sudo has been configured. In the following sections, we will use $(whoami) whenever the login of your work user is required in a command line. This is a shell command that will substitute your login in the command you are typing.

Some operations will definitely be easier if you have a GitHub account. If you don't have one already, go to https://github.com and create one.

To install Odoo from a source, you need to follow these steps:

1. Run the following commands to install the main dependencies:

$ sudo apt-get update
$ sudo apt-get install -y git python3.5 postgresql nano virtualenv xz-utils wget fontconfig libfreetype6 libx11-6 libxext6 libxrender1 xfonts-75dpi

2. Download and install wkhtmltopdf:

$ wget -O wkhtmltox.tar.xz \ https://github.com/wkhtmltopdf/wkhtmltopdf/releases/download/0.12.4/wkhtmltox-0.12.4_linux-generic-amd64.tar.xz 
$ tar xvf wkhtmltox.tar.xz
$ sudo mv wkhtmltox/lib/* /usr/local/lib/
$ sudo mv wkhtmltox/bin/* /usr/local/bin/
$ sudo mv wkhtmltox/share/man/man1 /usr/local/share/man/

3. Now, use the following code to install the build dependencies:

$ sudo apt-get install -y gcc python3.5-dev libxml2-dev \
libxslt1-dev libevent-dev libsasl2-dev libssl1.0-dev libldap2-dev \
libpq-dev libpng-dev libjpeg-dev

4. Configure PostgreSQL:

$ sudo -u postgres createuser --createdb $(whoami)
$ createdb $(whoami)

5. Configure git:

$ git config --global user.name "Your Name"
$ git config --global user.email youremail@example.com

6. Clone the Odoo code base:

$ mkdir ~/odoo-dev
$ cd ~/odoo-dev
$ git clone -b 12.0 --single-branch\ https://github.com/odoo/odoo.git
$ cd odoo

7. Create an odoo-12.0 virtual environment and activate it:

$ virtualenv -p python3 ~/odoo-12.0
$ source ~/odoo-12.0/bin/activate

8. Install the Python dependencies of Odoo in virtualenv:

$ pip3 install -r requirements.txt

9. Create and start your first Odoo instances:

$ createdb odoo-test
$ python3 odoo-bin -d odoo-test --addons-path=addons \ 
--db-filter=odoo-test$

10. Point your browser to http://localhost:8069 and authenticate it by using the admin account and using admin as the password.

Dependencies come from various sources. First, you have the core dependencies of Odoo, the Python interpreter, which is used to run the source code, and the PostgreSQL database server, which is used to store the instance data. Git is used for source code versioning and getting the source code of Odoo itself.

Since we will need to edit some files as root or as postgres (the PostgreSQL administrative user) on our server, we need to install a console-based text editor. We suggest nano for this as it is very simple to use, but feel free to choose any editor that you feel at ease with, as long as it works on the Console. For example, you can use vim, e3, or emacs-nox.

Wkhtmltopdf is a runtime dependency of Odoo that's used to produce PDF reports. The version that's required by Odoo 12.0 is 0.12.4, which is not included in the current GNU/Linux distributions. Fortunately for us, the maintainers of wkhtmltopdf provide pre-built packages for various distributions at http://wkhtmltopdf.org/downloads.html.

There are lots of other runtime dependencies that are Python modules, which we can install using pip3 in a virtual environment. However, some of these Python modules can feature some dependencies on native C libraries, for which the Python bindings need to be compiled. Consequently, we install the development packages for these C libraries as well as the Python development package and a C compiler. Once these build dependencies are installed, we can use pip3 install -r requirements.txt (a file that comes from the Odoo source code distribution) to download, compile, and install the Python modules.

Python virtual environments, or virtualenv for short, are isolated Python workspaces. These are very useful to Python developers because they allow different workspaces with different versions of various Python libraries to be installed, possibly on different Python interpreter versions.

You can create as many environments as you wish using the virtualenv -p python3 path/to/newenv command. This will create a newenv directory in the specified location, containing a bin/ subdirectory and a lib/python3.5 subdirectory. Don't forget -p python3, or you are likely to get a Python 2.7 virtual environment that won't be able to run Odoo 12.0.

In bin/, you will find several scripts:

• activate: This script is not executed and is sourced using the shell's built-in source command. This will activate the environment by adjusting the PATH environment variable to include the bin/ directory of virtualenv. It also installs a shell function called deactivate, which you can run in order to exit virtualenv, and changes the shell prompt to let you know which virtualenv is currently activated.
• pip3: This is a special version of the pip3 command that acts inside virtualenv only.
• python3: This is a wrapper around your system's Python interpreter, which uses the packages that have been installed in virtualenv.

There are two main ways of using a virtualenv. You may activate it, as shown in this recipe (and call deactivate when you're done), or you may use the scripts in the bin/ directory of the environment explicitly by calling them with their full path, in which case you don't need to activate the virtualenv script. This is mainly a matter of taste, so you should experiment and find out which style suits you better.

You may have executable Python scripts within the first line. This should look as follows:

#! /usr/bin/env python3

These will be easier to use with an activated virtualenv script.

This is the case with the odoo-bin script, which you can call in the following way:

$ ./odoo-bin -d odoo-test --addons-path=addons --db-filter=odoo-test

On a GNU/Linux system, Odoo uses the psycopg2 Python library to connect with a PostgreSQL database. Odoo works very well with the default values, which are used to access a PostgreSQL database with psycopg2. It uses the following default values:

• By default, psycopg2 tries to connect to a database with the same username as the current user on local connections, which enables password-less authentication
• The local connection uses Unix domain sockets
• The database server listens on port 5432

There is nothing special to do here, so we simply use the postgres administrative user to create a database user who shares our login name and gives it the right to create new databases. We then create a new database with the same name as the new user. This will be used as a default database when we use the psql command.

When on a development server, it is okay to give the PostgreSQL user more rights and use the --superuser command-line option rather than just --createdb. The net effect is that this user can then also create other users and globally manage the database instance. If you feel that --superuser is too much, you may still want to use --createrole in addition to --createdb when creating your database user. Avoid doing this on production servers as it will give additional leverage to an attacker exploiting a vulnerability in some part of the deployed code (refer to Chapter 3, Server Deployment).

If you want to use a database user with a different login, you will need to provide a password for the user. This is done by passing the --pwprompt flag on the command line when creating the user, in which case the command will prompt you for the password.

If the user has already been created and you want to set a password (or modify a forgotten password), you can use the following command:

$ psql -c "alter role $(whoami) with password 'newpassword'"

At some point in this book, you will need to use git commit. This will fail unless some basic configuration is performed; therefore, you need to provide Git with your name and email address. Git will remind you to do this with a nice error message, but you may as well do it now.

Downloading the Odoo code base is done by performing a git clone operation; be patient, as this will take some time. The --branch 12.0 --single-branch options avoid downloading other branches and save a little time. The --depth option can also be used to avoid downloading the whole repository history, but the downside of that option is that you will not be able to explore that history when looking for issues.

Odoo developers also propose nightly builds, which are available as tarballs and distribution packages. The main advantage of using git clone is that you will be able to update your repository when new bug fixes are committed in the source tree. You will also be able to easily test any proposed fixes and track regressions so that you can make your bug reports more precise and helpful for developers.

Now comes the moment you've been waiting for. To start our first instance, we first create a new empty database and then use the odoo-bin script with the following command-line arguments:

• -d database_name: Use this database by default.
• --db-filter=database_name$: Only try to connect to databases that match the supplied regular expression. One Odoo installation can serve multiple instances that live in separate databases, and this argument limits the available databases. The trailing $ is important as the regular expression is used in match mode; this allows to to avoid selecting names starting with the specified string.
• --addons-path=directory1,directory2,...: This is a comma-separated list of directories in which Odoo will look for add-ons. This list is scanned at instance creation time to populate the list of available add-on modules in the instance.

If you are using a database user with a database login that is different from your Linux login, you need to pass the following additional arguments:

• --db_host=localhost: Use a TCP connection to the database server
• --db_user=database_username: Use the specified database login
• --db_password=database_password: This is the password for authenticating against the PostgreSQL server

To get an overview of all available options, use the --help argument. We will see more of the odoo-bin script later in this chapter, as well as in Chapter 2, Managing Odoo Server Instances.

When Odoo is started on an empty database, it will first create the database structure that's needed to support its operations. It will also scan the add-ons path to find the available add-on modules and insert some into the initial records in the database. This includes the admin user with the default admin password, which you will use for authentication.

Odoo includes an HTTP server. By default, it listens on all local network interfaces on TCP port 8069, so pointing your web browser to http://localhost:8069/ leads you to your newly created instance.

We will often want to use custom or community modules with our Odoo instance. Keeping them in a separate directory makes it easier to install upgrades to Odoo or troubleshoot issues from our custom modules. We just have to add that directory to the add-ons path and they will be available in our instance, just like the core modules are.

It is possible to think about this module directory as an Odoo environment. The Odoo start command makes it easy to organize Odoo instances as directories, each with its own modules.

For this recipe, we need to have already installed Odoo. We are assuming that it will be located at ~/odoo-dev/odoo, and that virtualenv has been activated.

This means that the following command should successfully start an Odoo server:

$ ~/odoo-dev/odoo/odoo-bin

To create a work environment for your instance, you need to follow these steps:

1. Change to the directory where Odoo is:

$ cd ~/odoo-dev

2. Choose a name for the environment and create a directory for it:

$ mkdir my-odoo

3. Change to that directory and start an Odoo server instance for that environment:

$ cd my-odoo/
$ ../odoo/odoo-bin start

The Odoo start command is a shortcut to start a server instance using the current directory. The directory name is automatically used as the database name (for the -d option), and the current directory is automatically added to the add-ons path (the --addons-path option), as long as it contains an Odoo add-on module. In the preceding recipe, you won't see the current directory in the add-ons path because it doesn't contain any modules yet.

By default, the current directory is used, but the --path option allows you to set a specific path that you can use instead. For example, this will work from any directory:

$ ~/odoo-dev/odoo/odoo-bin start --path=~/odoo-dev/my-odoo

The database to use can also be overridden using the usual -d option. In fact, all of the other usual odoo-bin command-line arguments will work, except --addons-path. For example, to set the server listening port, use the following command:

$ ../odoo/odoo-bin start -p 8080 -i base

As we can see, the Odoo start command can be a convenient way to quick-start Odoo instances with their own module directory.

When working with Odoo, all of the data of your instance is stored in a PostgreSQL database. All of the standard database management tools you are used to are available, but Odoo also proposes a web interface for some common operations.

We are assuming that your work environment is set up and that you have an instance running. Do not start this using the odoo-bin start command that was shown in the previous recipe, as this configures the server with some options that interfere with multi-database management.

The Odoo database management interface provides tools to create, duplicate, remove, back up, and restore a database. There is also a way to change the master password, which is used to protect access to the database management interface.

To access the database, the following steps need to be performed:

1. Go to the login screen of your instance (if you are authenticated, log out).
2. Click on the Manage Databases link. This will navigate to http://localhost:8069/web/database/manager (you can also point your browser directly to that URL).

If you've set up your instance with default values and haven't modified it yet, as we will explain in the following section, the database management screen will display a warning, telling you that the master password hasn't been set and will advise you to set one with a direct link:

To set the master password, you need to perform the following steps:

1. Click on the Set Master Password button. You will get a dialog box asking you to provide the New Master Password:

2. Type in a non-trivial new password and click on Continue

If the master password is already set, click on the Set Master Password button at the bottom of the screen to change it. In the displayed dialog box, type the previous master password and the new one and then click on Continue.

This dialog box can be used to create a new database instance that will be handled by the current Odoo server:

1. In the database management window, click on the Create Database button, which can be found at the bottom of the screen:

2. Fill in the form, as follows:
   • Master Password: This is the master password for this instance.
   • Database Name: Input the name of the database you wish to create.
   • Password: Type in the password you want to set for the admin user of the new instance.
   • Phone Number: Set the phone number (optional).
   • Language: Select the language you wish to be installed by default in the new database in the drop-down list.
   • Country: Select the country of the main company in the drop-down list. Selecting this will automatically configure a few things, such as company currency.
   • Load demonstration data: Check this box to obtain demonstration data. This is useful for running interactive tests or setting up a demonstration for a customer, but it should not be checked for a database that is designed to contain production data.

3. Click on the Continue button and wait a while until the new database is initialized. You will then be redirected to the instance and connected as the administrator.

Often, you will have an existing database, and you will want to experiment with it to try a procedure or run a test, but without modifying the existing data. The solution here is simple: duplicate the database and run the test on the copy. Repeat this as many times as required:

1. In the database management screen, click on the Duplicate Database link next to the name of the database you wish to clone:

2. Fill in the form as follows:
   
   • Master Password: This is the master password of the Odoo server
   • New Name: The name you want to give to the copy

3. Click on the Continue button.
4. You can then click on the name of the newly created database in the database management screen to access the login screen for that database.

When you have finished your tests, you will want to clean up the duplicated databases. To do this, perform the following steps:

1. In the database management screen, click on the Delete Database link next to the name of the database you want to remove:

2. Fill in the form and enter the Master Password, which is the master password of the Odoo server.
3. Click on the Delete button.

For creating a backup, the following steps need to be performed:

1. In the database management screen, click on the Backup Database link next to the database you want to back up:

2. Fill in the form:
   • Master Password: This is the master password of the Odoo server.
   • Backup Format: Always use zip for a production database, as it is the only real full backup format. Only use the pg_dump format for a development database when you don't really care about the file store.

3. Click on the Backup button. The backup file will then be downloaded to your browser.

If you need to restore a backup, this is what you need to do:

1. In the database management screen, click on the Restore Database button at the bottom of the screen:

2. Fill in the form:
   • Master Password: This is the master password of the Odoo server.
   • File: This is a previously downloaded Odoo backup.
   • Database Name: Provide the name of the database in which the backup will be restored. The database must not exist on the server.
   • This database might have been moved or copied: Choose This database was moved if the original database was on another server or if it has been deleted from the current server. Otherwise, choose This database is a copy, which is the safe default option.
     
3. Click on the Continue button.

These features, apart from the Change master password screen, run PostgreSQL administration commands on the server and report back through the web interface.

The master password is a very important piece of information that only lives in the Odoo server configuration file and is never stored in the database. There used to be a default value of admin, but using this value is a security liability, which is well-known. In Odoo v9 and later, this is identified as an unset master password, and you are urged to change it when accessing the database administration interface. Even if it is stored in the configuration file under the admin_passwd entry, this is not the same as the password of the admin user; these are two independent passwords. The master password is set for an Odoo server process, which itself can handle multiple database instances, each of which has an independent admin user with their own password.

To create a new database, Odoo uses the PostgreSQL createdb utility and calls the internal Odoo function to initialize the new database in the same way as when you start Odoo on an empty database.

To duplicate a database, Odoo uses the --template option of createdb, passing the original database as an argument. This essentially duplicates the structure of the template database in the new database using internal and optimized PostgreSQL routines, which is much faster than creating a backup and restoring it (especially when using the web interface, which requires downloading the backup file and uploading it again).

Backup and restore operations use the pg_dump and pg_restore utilities, respectively. When using the zip format, the backup will also include a copy of the file store that contains a copy of the documents when you configure Odoo to not keep these in the database, which is the default option in 12.0. Unless you change it, these files live in ~/.local/share/Odoo/filestore.

Experienced Odoo developers generally don't use the database management interface and perform operations from the command line. To initialize a new database with demo data, for instance, the following one-liner can be used:

$ createdb testdb && odoo-bin -d testdb

The additional bonus of this command line is that you can request the installation of add-ons while you are using, for instance, -i sale,purchase,stock (more on this in Chapter 2, Managing Odoo Server Instances).

To duplicate a database, stop the server and run the following commands:

$ createdb -T dbname newdbname
$ cd ~/.local/share/Odoo/filestore # adapt if you have changed the data_dir
$ cp -r dbname newdbname
$ cd -

Note that, in the context of development, the file store is often omitted.

To remove an instance, run the following command:

$ dropdb dbname
$ rm -rf ~/.local/share/Odoo/filestore/dbname

To create a backup (assuming that the PostgreSQL server is running locally), use the following command:

$ pg_dump -Fc -f dbname.dump dbname
$ tar cjf dbname.tgz dbname.dump ~/.local/share/Odoo/filestore/dbname

To restore the backup, run the following command:

$ tar xf dbname.tgz
$ pg_restore -C -d dbname dbname.dump

The odoo-bin script has dozens of options, and it is tedious to remember them, all as well as remembering to set them properly when starting the server. Fortunately, it is possible to store them all in a configuration file and to only specify by hand the ones you want to alter, for example, for development.

To generate a configuration file for your Odoo instance, run the following command:

$ ./odoo-bin --save --config myodoo.cfg --stop-after-init

You can add additional options, and their values will be saved in the generated file. All of the unset options will be saved with their default value set. To get a list of possible options, use the following command:

$ ./odoo-bin --help | less

This will provide you with some help about what the various options perform. To convert from the command-line form into the configuration form, use the long option name, remove the leading dashes, and convert the dashes in the middle into underscores:
--without-demo then becomes without_demo. This works for most options, but there are a few exceptions, which are listed in the following section.

Edit the myodoo.cfg file (use the table in the following section for some parameters you may want to change). Then, to start the server with the saved options, run the following command:

$ ./odoo-bin -c myodoo.cfg

At startup, Odoo loads its configuration in three passes. First, a set of default values for all options is initialized from the source code, then the configuration is parsed, and any value that's defined in the file overrides the defaults. Finally, the command-line options are analyzed and their values override the configuration that was obtained from the previous pass.

As we mentioned earlier, the names of the configuration variables can be found from the names of the command-line options by removing the leading dashes and converting the middle dashes into underscores. There are a few exceptions to this, notably the following:

Here's a list of options that are commonly set through the configuration file:

Some options are not used in config files, but they are widely used during development:

When using Odoo as a developer, you need to know how to activate developer mode in the web interface so that you can access the technical settings menu and developer information. Enabling debug mode will expose several advance configuration options and fields. These options and fields are hidden in Odoo for better usability because they are not used on a daily basis.

To activate developer mode in the web interface, follow these steps:

1. Connect to your instance and authenticate as admin.
2. Go to the Settings menu.
3. Locate the Share the love card, which should be on the right-hand side of the screen:
   
4. Click on the Activate the developer mode link.
5. Wait for the UI to reload.

To exit developer mode, you can do either of the following:

• Edit the URL and remove that string
• Use the Deactivate the developer mode link displayed in the Share the love card when the developer mode is active

Lots of developers are using browser extensions to toggle debug mode. By using this, you can toggle debug mode quickly without accessing the settings menu. These extensions are available for Firefox and Chrome. Take a look at the given screenshot, it will help you to identify the plugin in the Chrome store:

In developer mode, two things happen:

• You get tooltips when hovering over a field in a form view or over a column in list view, providing technical information about the field (internal name, type, and so on)
• A drop-down menu with a Bug icon is displayed next to the user's menu in the top-right corner, giving access to technical information about the model being displayed, the various related view definitions, the workflow, custom filter management, and so on

There is a variant of the developer mode: the Developer mode (with assets). This mode behaves like the normal developer mode, but additionally, the JavaScript and CSS code that's sent to the browser is not minified, which means that the web development tools of your browser are easy to use for debugging the JavaScript code (more on this in Chapter 15, Web Client Development).

In the first recipe, we saw how to install Odoo from source using the git repository. The main benefit of this setting is being able to update the source code of Odoo using git to get the latest bug fixes.

Stop any instance that's currently running with the Odoo source you are about to update, and then make a backup of all of the databases you care about in case something goes wrong. This is obviously something you need to do for production databases. Refer to the Managing Odoo server databases recipe of this chapter for further instructions.

Next, make a note of the current version of the source you are running. The best way to do this is by creating a lightweight tag using the following command:

$ cd ~/odoo-dev/odoo
$ git checkout 12.0
$ git tag 12.0-before-update-$(date --iso)

To update the source code of Odoo, use the following command:

$ git pull –-ff-only origin 12.0

This will fetch the latest version of the source code that's committed to the current branch.

To update an instance running on this code, run the following command:

$ ./odoo-bin -c myodoo.cfg --stop-after-init -u base

If you don't have a database set in the configuration file, you will have to add the
-d database_name option. This command is to be repeated for all of the instances that are running with this version of the source code.

If the update fails, don't panic, because you have backups:

1. Read the error message carefully and save it to a file, as it will be useful for making a bug report later.
2. If you cannot figure out what the problem is, restore the service and the Odoo source code to the previous version, which is known to work using the tag you set before updating the source version:

$ git reset --hard 12.0-before-update-$(date --iso)

3. Drop the broken databases and restore them from the backups you made (refer to the Managing Odoo server databases recipe of this chapter for instructions).
4. Restart your instances and tell your users that the upgrade has been postponed.

Updating the source code is done by ensuring that we are on the correct branch using git checkout and then fetching the new revisions using git pull. The --ff-only option will cause a failure if you have local commits that aren't present in the remote repository. If this happens and you want to keep your changes, you can use git pull (without --ff-only) to merge the remote changes with yours. If not, use git reset --hard origin/12.0 to force the update, hence discarding your local modifications.

The update command uses the following options:

• -c: Specifies the configuration file
• --stop-after-init: Stops the instance when the update is over
• -u base or --update base: Requests the update of the base module

When updating a module, Odoo does the following:

• It updates the database structure for the models defined in the module for which the structure changes. For updates on the stable branch of Odoo, there should be no such changes, but this can happen for your own add-ons or third-party add-ons.
• It updates the database records that are stored in data files of the module, most notably, the views. It then recursively updates the installed modules that have declared a dependency on the module.

Since the base module is an implicit dependency of all Odoo modules, updating it will trigger an update of all of the installed modules in your instance. To update all installed modules, the all alias can be used instead of base.