293 lines
7.8 KiB
ReStructuredText
293 lines
7.8 KiB
ReStructuredText
.. _playbook_debugger:
|
|
|
|
Playbook Debugger
|
|
=================
|
|
|
|
.. contents:: Topics
|
|
|
|
Ansible includes a debugger as part of the strategy plugins. This debugger enables you to debug a task.
|
|
You have access to all of the features of the debugger in the context of the task. You can then, for example, check or set the value of variables, update module arguments, and re-run the task with the new variables and arguments to help resolve the cause of the failure.
|
|
|
|
There are multiple ways to invoke the debugger.
|
|
|
|
Using the debugger keyword
|
|
++++++++++++++++++++++++++
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
The ``debugger`` keyword can be used on any block where you provide a ``name`` attribute, such as a play, role, block or task.
|
|
|
|
The ``debugger`` keyword accepts several values:
|
|
|
|
always
|
|
Always invoke the debugger, regardless of the outcome
|
|
|
|
never
|
|
Never invoke the debugger, regardless of the outcome
|
|
|
|
on_failed
|
|
Only invoke the debugger if a task fails
|
|
|
|
on_unreachable
|
|
Only invoke the debugger if the a host was unreachable
|
|
|
|
on_skipped
|
|
Only invoke the debugger if the task is skipped
|
|
|
|
These options override any global configuration to enable or disable the debugger.
|
|
|
|
On a task
|
|
`````````
|
|
|
|
::
|
|
|
|
- name: Execute a command
|
|
command: "false"
|
|
debugger: on_failed
|
|
|
|
On a play
|
|
`````````
|
|
|
|
::
|
|
|
|
- name: Play
|
|
hosts: all
|
|
debugger: on_skipped
|
|
tasks:
|
|
- name: Execute a command
|
|
command: "true"
|
|
when: False
|
|
|
|
When provided at a generic level and a more specific level, the more specific wins::
|
|
|
|
- name: Play
|
|
hosts: all
|
|
debugger: never
|
|
tasks:
|
|
- name: Execute a command
|
|
command: "false"
|
|
debugger: on_failed
|
|
|
|
|
|
Configuration or environment variable
|
|
+++++++++++++++++++++++++++++++++++++
|
|
|
|
.. versionadded:: 2.5
|
|
|
|
In ansible.cfg::
|
|
|
|
[defaults]
|
|
enable_task_debugger = True
|
|
|
|
As an environment variable::
|
|
|
|
ANSIBLE_ENABLE_TASK_DEBUGGER=True ansible-playbook -i hosts site.yml
|
|
|
|
When using this method, any failed or unreachable task will invoke the debugger,
|
|
unless otherwise explicitly disabled.
|
|
|
|
As a Strategy
|
|
+++++++++++++
|
|
|
|
.. note::
|
|
This is a backwards compatible method, to match Ansible versions before 2.5,
|
|
and may be removed in a future release
|
|
|
|
To use the ``debug`` strategy, change the ``strategy`` attribute like this::
|
|
|
|
- hosts: test
|
|
strategy: debug
|
|
tasks:
|
|
...
|
|
|
|
If you don't want change the code, you can define ``ANSIBLE_STRATEGY=debug``
|
|
environment variable in order to enable the debugger, or modify ``ansible.cfg`` such as::
|
|
|
|
[defaults]
|
|
strategy = debug
|
|
|
|
|
|
Examples
|
|
++++++++
|
|
|
|
For example, run the playbook below::
|
|
|
|
- hosts: test
|
|
debugger: on_failed
|
|
gather_facts: no
|
|
vars:
|
|
var1: value1
|
|
tasks:
|
|
- name: wrong variable
|
|
ping: data={{ wrong_var }}
|
|
|
|
The debugger is invoked since the *wrong_var* variable is undefined.
|
|
|
|
Let's change the module's arguments and run the task again
|
|
|
|
.. code-block:: none
|
|
|
|
PLAY ***************************************************************************
|
|
|
|
TASK [wrong variable] **********************************************************
|
|
fatal: [192.0.2.10]: FAILED! => {"failed": true, "msg": "ERROR! 'wrong_var' is undefined"}
|
|
Debugger invoked
|
|
[192.0.2.10] TASK: wrong variable (debug)> p result._result
|
|
{'failed': True,
|
|
'msg': 'The task includes an option with an undefined variable. The error '
|
|
"was: 'wrong_var' is undefined\n"
|
|
'\n'
|
|
'The error appears to have been in '
|
|
"'playbooks/debugger.yml': line 7, "
|
|
'column 7, but may\n'
|
|
'be elsewhere in the file depending on the exact syntax problem.\n'
|
|
'\n'
|
|
'The offending line appears to be:\n'
|
|
'\n'
|
|
' tasks:\n'
|
|
' - name: wrong variable\n'
|
|
' ^ here\n'}
|
|
[192.0.2.10] TASK: wrong variable (debug)> p task.args
|
|
{u'data': u'{{ wrong_var }}'}
|
|
[192.0.2.10] TASK: wrong variable (debug)> task.args['data'] = '{{ var1 }}'
|
|
[192.0.2.10] TASK: wrong variable (debug)> p task.args
|
|
{u'data': '{{ var1 }}'}
|
|
[192.0.2.10] TASK: wrong variable (debug)> redo
|
|
ok: [192.0.2.10]
|
|
|
|
PLAY RECAP *********************************************************************
|
|
192.0.2.10 : ok=1 changed=0 unreachable=0 failed=0
|
|
|
|
This time, the task runs successfully!
|
|
|
|
.. _available_commands:
|
|
|
|
Available Commands
|
|
++++++++++++++++++
|
|
|
|
.. _pprint_command:
|
|
|
|
p(print) *task/task_vars/host/result*
|
|
`````````````````````````````````````
|
|
|
|
Print values used to execute a module::
|
|
|
|
[192.0.2.10] TASK: install package (debug)> p task
|
|
TASK: install package
|
|
[192.0.2.10] TASK: install package (debug)> p task.args
|
|
{u'name': u'{{ pkg_name }}'}
|
|
[192.0.2.10] TASK: install package (debug)> p task_vars
|
|
{u'ansible_all_ipv4_addresses': [u'192.0.2.10'],
|
|
u'ansible_architecture': u'x86_64',
|
|
...
|
|
}
|
|
[192.0.2.10] TASK: install package (debug)> p task_vars['pkg_name']
|
|
u'bash'
|
|
[192.0.2.10] TASK: install package (debug)> p host
|
|
192.0.2.10
|
|
[192.0.2.10] TASK: install package (debug)> p result._result
|
|
{'_ansible_no_log': False,
|
|
'changed': False,
|
|
u'failed': True,
|
|
...
|
|
u'msg': u"No package matching 'not_exist' is available"}
|
|
|
|
.. _update_args_command:
|
|
|
|
task.args[*key*] = *value*
|
|
``````````````````````````
|
|
|
|
Update module's argument.
|
|
|
|
If you run a playbook like this::
|
|
|
|
- hosts: test
|
|
strategy: debug
|
|
gather_facts: yes
|
|
vars:
|
|
pkg_name: not_exist
|
|
tasks:
|
|
- name: install package
|
|
apt: name={{ pkg_name }}
|
|
|
|
Debugger is invoked due to wrong package name, so let's fix the module's args::
|
|
|
|
[192.0.2.10] TASK: install package (debug)> p task.args
|
|
{u'name': u'{{ pkg_name }}'}
|
|
[192.0.2.10] TASK: install package (debug)> task.args['name'] = 'bash'
|
|
[192.0.2.10] TASK: install package (debug)> p task.args
|
|
{u'name': 'bash'}
|
|
[192.0.2.10] TASK: install package (debug)> redo
|
|
|
|
Then the task runs again with new args.
|
|
|
|
.. _update_vars_command:
|
|
|
|
task_vars[*key*] = *value*
|
|
``````````````````````````
|
|
|
|
Update ``task_vars``.
|
|
|
|
Let's use the same playbook above, but fix ``task_vars`` instead of args::
|
|
|
|
[192.0.2.10] TASK: install package (debug)> p task_vars['pkg_name']
|
|
u'not_exist'
|
|
[192.0.2.10] TASK: install package (debug)> task_vars['pkg_name'] = 'bash'
|
|
[192.0.2.10] TASK: install package (debug)> p task_vars['pkg_name']
|
|
'bash'
|
|
[192.0.2.10] TASK: install package (debug)> update_task
|
|
[192.0.2.10] TASK: install package (debug)> redo
|
|
|
|
Then the task runs again with new ``task_vars``.
|
|
|
|
.. note::
|
|
In 2.5 this was updated from ``vars`` to ``task_vars`` to not conflict with the ``vars()`` python function.
|
|
|
|
.. _update_task_command:
|
|
|
|
u(pdate_task)
|
|
`````````````
|
|
|
|
.. versionadded:: 2.8
|
|
|
|
This command re-creates the task from the original task data structure, and templates with updated ``task_vars``
|
|
|
|
See the above documentation for :ref:`update_vars_command` for an example of use.
|
|
|
|
.. _redo_command:
|
|
|
|
r(edo)
|
|
``````
|
|
|
|
Run the task again.
|
|
|
|
.. _continue_command:
|
|
|
|
c(ontinue)
|
|
``````````
|
|
|
|
Just continue.
|
|
|
|
.. _quit_command:
|
|
|
|
q(uit)
|
|
``````
|
|
|
|
Quit from the debugger. The playbook execution is aborted.
|
|
|
|
Use with the free strategy
|
|
++++++++++++++++++++++++++
|
|
|
|
Using the debugger on the ``free`` strategy will cause no further tasks to be queued or executed
|
|
while the debugger is active. Additionally, using ``redo`` on a task to schedule it for re-execution
|
|
may cause the rescheduled task to execute after subsequent tasks listed in your playbook.
|
|
|
|
|
|
.. seealso::
|
|
|
|
:ref:`playbooks_intro`
|
|
An introduction to playbooks
|
|
`User Mailing List <https://groups.google.com/group/ansible-devel>`_
|
|
Have a question? Stop by the google group!
|
|
`irc.freenode.net <http://irc.freenode.net>`_
|
|
#ansible IRC chat channel
|