This section discusses the behavioral changes between Ansible 2.6 and Ansible 2.7.
It is intended to assist in updating your playbooks, plugins and other parts of your Ansible infrastructure so they will work with this version of Ansible.
We suggest you read this page along with `Ansible Changelog for 2.7 <https://github.com/ansible/ansible/blob/stable-2.7/changelogs/CHANGELOG-v2.7.rst>`_ to understand what updates you may need to make.
Ansible 2.7 makes a small change to variable precedence when loading roles, resolving a bug, ensuring that role loading matches :ref:`variable precedence expectations <ansible_variable_precedence>`.
Before Ansible 2.7, when loading a role, the variables defined in the role's ``vars/main.yml`` and ``defaults/main.yml`` were not available when parsing the role's ``tasks/main.yml`` file. This prevented the role from utilizing these variables when being parsed. The problem manifested when ``import_tasks`` or ``import_role`` was used with a variable defined in the role's vars or defaults.
In Ansible 2.7, role ``vars`` and ``defaults`` are now parsed before ``tasks/main.yml``. This can cause a change in behavior if the same variable is defined at the play level and the role level with different values, and leveraged in ``import_tasks`` or ``import_role`` to define the role or file to import.
In Ansible 2.7 a new module argument named ``public`` was added to the ``include_role`` module that dictates whether or not the role's ``defaults`` and ``vars`` will be exposed outside of the role, allowing those variables to be used by later tasks. This value defaults to ``public: False``, matching current behavior.
``import_role`` does not support the ``public`` argument, and will unconditionally expose the role's ``defaults`` and ``vars`` to the rest of the playbook. This functionality brings ``import_role`` into closer alignment with roles listed within the ``roles`` header in a play.
There is an important difference in the way that ``include_role`` (dynamic) will expose the role's variables, as opposed to ``import_role`` (static). ``import_role`` is a pre-processor, and the ``defaults`` and ``vars`` are evaluated at playbook parsing, making the variables available to tasks and roles listed at any point in the play. ``include_role`` is a conditional task, and the ``defaults`` and ``vars`` are evaluated at execution time, making the variables available to tasks and roles listed *after* the ``include_role`` task.
As of Ansible 2.7, `include_tasks` and `import_tasks` can no longer accept inline variables. Instead of using inline variables, tasks should supply variables under the ``vars`` keyword.
**OLD** In Ansible 2.6 (and earlier) the following was valid syntax for specifying variables:
..code-block:: yaml
- include_tasks: include_me.yml variable=value
**NEW** In Ansible 2.7 the task should be changed to use the ``vars`` keyword:
..note:: The use of the ``__file__`` variable is deprecated in Ansible 2.7 and **will be eliminated in Ansible 2.8**. This is much quicker than our usual 4-release deprecation cycle.
We are deprecating the use of the ``__file__`` variable to refer to the file containing the currently-running code. This common Python technique for finding a filesystem path does not always work (even in vanilla Python). Sometimes a Python module can be imported from a virtual location (like inside of a zip file). When this happens, the ``__file__`` variable will reference a virtual location pointing to inside of the zip file. This can cause problems if, for instance, the code was trying to use ``__file__`` to find the directory containing the python module to write some temporary information.
Before the introduction of AnsiBallZ in Ansible 2.1, using ``__file__`` worked in ``AnsibleModule`` sometimes, but any module that used it would fail when pipelining was turned on (because the module would be piped into the python interpreter's standard input, so ``__file__`` wouldn't contain a file path). AnsiBallZ unintentionally made using ``__file__`` work, by always creating a temporary file for ``AnsibleModule`` to reside in.
Ansible 2.8 will no longer create a temporary file for ``AnsibleModule``; instead it will read the file out of a zip file. This change should speed up module execution, but it does mean that starting with Ansible 2.8, referencing ``__file__`` will always fail in ``AnsibleModule``.
If you are the author of a third-party module which uses ``__file__`` with ``AnsibleModule``, please update your module(s) now, while the use of ``__file__`` is deprecated but still available. The most common use of ``__file__`` is to find a directory to write a temporary file. In Ansible 2.5 and above, you can use the ``tmpdir`` attribute on an ``AnsibleModule`` instance instead, as shown in this code from the :ref:`apt module <apt_module>`:
The use of ``squash_actions`` to invoke a package module, such as "yum", to only invoke the module once is deprecated, and will be removed in Ansible 2.11.
Instead of relying on implicit squashing, tasks should instead supply the list directly to the ``name``, ``pkg`` or ``package`` parameter of the module. This functionality has been supported in most modules since Ansible 2.3.
**OLD** In Ansible 2.6 (and earlier) the following task would invoke the "yum" module only 1 time to install multiple packages
..code-block:: yaml
- name: Install packages
yum:
name: "{{ item }}"
state: present
with_items: "{{ packages }}"
**NEW** In Ansible 2.7 it should be changed to look like this:
..code-block:: yaml
- name: Install packages
yum:
name: "{{ packages }}"
state: present
Modules
=======
Major changes in popular modules are detailed here
* Prior to Ansible 2.7.10, the ``replace`` module did the opposite of what was intended when using the ``before`` and ``after`` options together. This now works properly but may require changes to tasks.
