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 of the Odoo developers are using GNU/Linux, and you are much more likely to get support from the community for OS-level issues occurring 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 some library has a different version than is 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 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 unchanged. Whatever Linux distribution you choose, you should have some notion of how to use it from the command line, and having a few ideas about system administration will certainly not cause any harm.

We assume that Linux is 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 pages, 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. Go to https://github.com and create one if you don't have one already.

To install Odoo from 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 \ node-less node-clean-css 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 this 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 [email protected]

6. Clone the Odoo code base:

$ mkdir ~/odoo-dev
$ cd ~/odoo-dev
$ git clone -b 11.0 --single-branch\ https://github.com/odoo/odoo.git
$ cd odoo

7. Create an odoo-11.0 virtual environment and activate it:

$ virtualenv -p python3 ~/odoo-11.0
$ source ~/odoo-11.0/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 using the admin account and admin as password.

Dependencies come from various sources. First, you have the core dependencies of Odoo, the Python interpreter that is used to run the source code, and the PostgreSQL database server 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 as it is very simple to use, but feel free to choose any editor with which you feel at ease as long as it works on the console, such as vim, e3, or emacs-nox.

Wkhtmltopdf is a runtime dependency of Odoo used to produce PDF reports. The version required by Odoo 11.0 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 on 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. Therefore, 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. They 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/ sub-directory and a lib/python3.5 subdirectory. Don't forget -p python3, or you are likely to get a python 2.7 virtual environment that will not be able to run Odoo 11.0.

In bin/, you will find several scripts:

• activate: The script is not executed; it is sourced using the shell built-in source command. This will activate the environment by adjusting the PATH environment variable to include the bin/ directory of the virtualenv. It also installs a shell function called deactivate, which you can run to exit the 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 the virtualenv only.
• python3: This is a wrapper around your system Python interpreter that uses the packages installed in the virtualenv.

There are two main ways of using a virtualenv. You may activate it as we show in the 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. This is mainly a matter of taste, so you should experiment and find out which style suits you better for which case.

You may have executable Python scripts with the first line looking like the following:

#! /usr/bin/env python3
 

These will be easier to use with an activated virtualenv.

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 works very well with the default values of psycopg2 that the Python module used to access a PostgreSQL database:

• Passwordless authentication if the database user has the same name as the current user on local connections
• Local connection uses Unix domain sockets
• The database server listens on port 5432

In that case, there is nothing special to do; we 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, which will be used as a default database when using the psql command.

When on a development server, it is okay to give the PostgreSQL user more rights and to 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 the book, you will need to use git commit. This will fail unless some basic configuration is performed; 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 11.0 --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 a 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 you can make your bug reports more precise and helpful for the 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 that database by default.
• --db-filter=database_name$: Only try to connect to databases matching the supplied regular expression. One Odoo installation can serve multiple instances living in separate databases, and this argument limits the available databases. The trailing $ is important as the regular expression is used in match mode; this avoids 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 addons. This list is scanned at the instance creation time to populate the list of available addon modules in the instance.

If you are using a database user with a database login 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: The password to use to authenticate against the PostgreSQL server

To get an overview of all of the available options, use the --help argument. We will see much more about the odoo-bin script 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 needed to support its operations. It will also scan the addons path to find the available addon modules, and insert some into the initial records in the database. This includes the admin user with the default password admin, which you will use to authenticate with.

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.

In the recipe, we downloaded the latest stable version of Odoo using the following command:

$ git clone -b 11.0 --single-branch https://github.com/odoo/odoo.git

This uses the official branch maintained by Odoo. One issue with this branch is that bug fixes contributed by the community are not always merged in a timely fashion. The Odoo Community Association (OCA) maintains a parallel branch in which fixes and improvements are peer-reviewed by the community and tend to be merged faster than on the official branch. It is not a fork of Odoo, and the latest version of Odoo is merged back into that branch daily. You may want to use it for your developments and deployments, in which case you need to clone Odoo like this:

$ git clone -b 11.0 --single-branch https://github.com/OCA/OCB.git odoo