Ansible 2.7 Porting Guide

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Ansible/docs/2.7/porting guides/porting guide 2.7


Ansible 2.7 Porting Guide

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 to understand what updates you may need to make.

This document is part of a collection on porting. The complete list of porting guides can be found at porting guides.

Command Line

If you specify --tags or --skip-tags multiple times on the command line, Ansible will merge the specified tags together. In previous versions of Ansible, you could set merge_multiple_cli_tags to False if you wanted to keep only the last-specified --tags. This config option existed for backwards compatibility. The overwriting behavior was deprecated in 2.3 and the default behavior was changed in 2.4. Ansible-2.7 removes the config option; multiple --tags are now always merged.

If you have a shell script that depends on setting merge_multiple_cli_tags to False, please upgrade your script so it only adds the --tags you actually want before upgrading to Ansible-2.7.

Python Compatibility

Ansible has dropped compatibility with Python-2.6 on the controller (The host where /usr/bin/ansible or /usr/bin/ansible-playbook is run). Modules shipped with Ansible can still be used to manage hosts which only have Python-2.6. You just need to have a host with Python-2.7 or Python-3.5 or greater to manage those hosts from.

One thing that this does affect is the ability to use /usr/bin/ansible-pull to manage a host which has Python-2.6. ansible-pull runs on the host being managed but it is a controller script, not a module so it will need an updated Python. Actively developed Linux distros which ship with Python-2.6 have some means to install newer Python versions (For instance, you can install Python-2.7 via an SCL on RHEL-6) but you may need to also install Python bindings for many common modules to work (For RHEL-6, for instance, selinux bindings and yum would have to be installed for the updated Python install).

The decision to drop Python-2.6 support on the controller was made because many dependent libraries are becoming unavailable there. In particular, python-cryptography is no longer available for Python-2.6 and the last release of pycrypto (the alternative to python-cryptography) has known security bugs which will never be fixed.

Playbook

Role Precedence Fix during Role Loading

Ansible 2.7 makes a small change to variable precedence when loading roles, resolving a bug, ensuring that role loading matches variable precedence expectations.

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.

include_role and import_role variable exposure

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.

include_tasks/import_tasks inline variables

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:

- include_tasks: include_me.yml variable=value

NEW In Ansible 2.7 the task should be changed to use the vars keyword:

- include_tasks: include_me.yml
  vars:
    variable: value

vars_prompt with unknown algorithms

vars_prompt now throws an error if the hash algorithm specified in encrypt is not supported by the controller. This increases the safety of vars_prompt as it previously returned None if the algorithm was unknown. Some modules, notably the user module, treated a password of None as a request not to set a password. If your playbook starts erroring because of this, change the hashing algorithm being used with this filter.

Deprecated

Expedited Deprecation: Removal of the params module option in ldap_attr and ldap_entry

The params module option in ldap_attr and ldap_entry are deprecated on a short cycle (to be removed in Ansible-2.10) due to circumventing Ansible’s normal option handling. In particular, if the bind_pw option is set with params, the value of the option could end up being placed in a logfile or displayed on stdout.

Expedited Deprecation: Use of __file__ in AnsibleModule

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 apt module:

-    tempdir = os.path.dirname(__file__)
-    package = os.path.join(tempdir, to_native(deb.rsplit('/', 1)[1]))
+    package = os.path.join(module.tmpdir, to_native(deb.rsplit('/', 1)[1]))

Using a loop on a package module via squash_actions

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

- name: Install packages
  yum:
    name: "{{ item }}"
    state: present
  with_items: "{{ packages }}"

NEW In Ansible 2.7 it should be changed to look like this:

- name: Install packages
  yum:
    name: "{{ packages }}"
    state: present

Modules

Major changes in popular modules are detailed here

  • The DEFAULT_SYSLOG_FACILITY configuration option tells Ansible modules to use a specific syslog facility when logging information on all managed machines. Due to a bug with older Ansible versions, this setting did not affect machines using journald with the systemd Python bindings installed. On those machines, Ansible log messages were sent to /var/log/messages, even if you set DEFAULT_SYSLOG_FACILITY. Ansible 2.7 fixes this bug, routing all Ansible log messages according to the value set for DEFAULT_SYSLOG_FACILITY. If you have DEFAULT_SYSLOG_FACILITY configured, the location of remote logs on systems which use journald may change.

Modules removed

The following modules no longer exist:

Deprecation notices

The following modules will be removed in Ansible 2.11. Please update your playbooks accordingly.

Noteworthy module changes

  • Security Issue Setting bind_pw with the params option for the ldap_entry and ldap_attr modules has been disallowed. If bind_pw was set with params, the value could have ended up in a logfile or displayed on stdout. Set bind_pw directly, with the modules’ options instead.
  • Check mode is now supported in the command and shell modules. However, only when creates or removes is specified. If either of these are specified, the module will check for existence of the file and report the correct changed status, if they are not included the module will skip like it had done previously.
  • The win_chocolatey module originally required the proxy_username and proxy_password to escape any double quotes in the value. This is no longer required and the escaping may cause further issues.
  • The win_uri module has removed the deprecated option use_basic_parsing, since Ansible 2.5 this option did nothing
  • The win_scheduled_task module has removed the following deprecated options:

    • executable, use path in an actions entry instead
    • argument, use arguments in an actions entry instead
    • store_password, set logon_type: password instead
    • days_of_week, use monthlydow in a triggers entry instead
    • frequency, use type, in a triggers entry instead
    • time, use start_boundary in a triggers entry instead
  • The interface_name module option for na_ontap_net_vlan has been removed and should be removed from your playbooks
  • The win_disk_image module has deprecated the return value mount_path, use mount_paths[0] instead. This will be removed in Ansible 2.11.
  • include_role and include_tasks can now be used directly from ansible (adhoc) and ansible-console:

    #> ansible -m include_role -a 'name=myrole' all
  • 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.

Plugins

  • The hash_password filter now throws an error if the hash algorithm specified is not supported by the controller. This increases the safety of the filter as it previously returned None if the algorithm was unknown. Some modules, notably the user module, treated a password of None as a request not to set a password. If your playbook starts erroring because of this, change the hashing algorithm being used with this filter.

Porting custom scripts

No notable changes.

Networking

No notable changes.

© 2012–2018 Michael DeHaan
© 2018–2019 Red Hat, Inc.
Licensed under the GNU General Public License version 3.
https://docs.ansible.com/ansible/2.7/porting_guides/porting_guide_2.7.html