Ansible: Access facts set by set_fact - ansible

I need to be able to set variables using tasks in Ansible. I use set_fact for this, but cannot seem to access the fact I set with this. What is wrong with the code below:
- name: kludge1
set_fact: fake_y = "{{ [] }}"
- name: Loop
debug:
msg: "{{ item }}"
with_items: "{{ fake_y }}"

You have spaces before and after =...
- name: kludge1
set_fact: fake_y="{{ [] }}"
Avoid var= shortcut syntax. Use original YAML syntax instead, it gives less errors:
- name: kludge1
set_fact:
fake_y: "{{ [] }}"

Related

A method for listing Ansible modules used by playbooks

I'm creating a requirements.yml in an Ansible project, and I want to identify all of the modules that need to be installed from ansible-galaxy that are used by project playbooks. ansible-doc --list --playbook-dir foo seems like the right tool for the job, but it lists all locally available modules, not just the ones which are actually used in the foo directory. ansible-galaxy list doesn't account for any which are needed but not installed.
Is there a way to do this where I don't end up writing a shell script to sed|awk|grep the info I want?
The best approach I've been able to come up with so far is to ansible-playbook --syntax-check each of the playbooks. This will throw errors such as
ERROR! the role 'foo' was not found ...
ERROR! couldn't resolve module/action 'bar'. This often indicates a misspelling, missing collection, or incorrect module path.
but this is not ideal because it exits as soon as any error occurs. I have to fix each one and run the syntax check again.
FWIW, as a concept, the playbook below lists the modules used in a role
- hosts: localhost
vars:
keywords:
- always
- become
- block
- loop
- loop_control
- name
- notify
- register
- tags
- vars
- when
tasks:
- name: The variable my_role_path is mandatory
assert:
that: my_role_path|d('')|length > 0
- name: Find tasks files
find:
path: "{{ my_role_path }}/tasks"
patterns: '*.yml,*.yaml'
recurse: true
register: result
- name: Create list of tasks
set_fact:
lft: "{{ lft|d([]) + lookup('file', item)|from_yaml }}"
loop: "{{ result.files|map(attribute='path')|list }}"
- name: Get list of keys
set_fact:
lfk: "{{ lfk|d([]) + item.keys()|list }}"
loop: "{{ lft }}"
- name: Get list of keys from block/rescue/always
set_fact:
lfk: "{{ lfk|d([]) + item.keys()|list }}"
loop: "{{ lft|json_query('[].[block, rescue, always]')|flatten }}"
- name: Display list of modules
debug:
var: lfk|unique|sort|difference(keywords)
For example, analyze the role systemd
shell> ansible-playbook pb.yml -e my_role_path=roles/ansible-role-systemd
...
lfk|unique|sort|difference(keywords):
- command
- file
- include_tasks
- meta
- systemd
- template
Complete the list of the keywords.
Use the tasks below to analyze a playbook
tasks:
- name: The variable my_playbook_path is mandatory
assert:
that: my_playbook_path|d('')|length > 0
- name: Create list of tasks
set_fact:
lft: "{{ _playbook|map(attribute='tasks')|flatten }}"
vars:
_playbook: "{{ lookup('file', my_playbook_path)|from_yaml }}"
- name: Get list of keys
set_fact:
lfk: "{{ lfk|d([]) + item.keys()|list }}"
loop: "{{ lft }}"
- name: Get list of keys from block/rescue/always
set_fact:
lfk: "{{ lfk|d([]) + item.keys()|list }}"
loop: "{{ lft|json_query('[].[block, rescue, always]')|flatten }}"
- name: Display list of modules
debug:
var: lfk|unique|sort|difference(keywords)
For example, analyzing the first playbook gives
lfk|unique|sort|difference(keywords):
- assert
- debug
- find
- set_fact

set path when file exists in Ansible yml code

I'm trying to set a var only when a file exists, here is one of my attempts
---
- hosts: all
tasks:
- stat:
path: '{{ srch_path_new }}/bin/run'
register: result
- vars: srch_path="{{ srch_path_new }}"
when: result.stat.exists
This also didn't work
- vars: srch_path:"{{ srch_path_new }}"
The task you are looking for is called set_fact: and is the mechanism ansible uses to declare arbitrary "host variables", sometimes called "hostvars", or (also confusingly) "facts"
The syntax would be:
- set_fact:
srch_path: "{{ srch_path_new }}"
when: result.stat.exists
Also, while vars: is a legal keyword on a Task, its syntax is the same as set_fact: (or the vars: on the playbook): a yaml dictionary, not a key:value pair as you had. For example:
- debug:
msg: hello, {{ friend }}
vars:
friend: Jane Doe
and be aware that vars: on a task exist only for that task

Ansible: exclude item(s) from lookup result

The following Ansible play:
- name: Fetch domains
vars:
domain_lines: "{{ lookup('file', domain_file).splitlines() }}"
debug:
msg: "Domains: {{ domain_lines }}"
reads and splits the lines from the following "domain_file":
test1.domain.tld
# test2.domain.tld
test3.domain.tld
test4.domain.tld
This works nicely. But now I'd like to skip/remove the lines starting with a hashtag. What's the best way to achieve this?
Use reject. The play below
- set_fact:
domain_selected: "{{ domain_lines|reject('regex', '^#(.*)$')|list }}"
- debug:
var: domain_selected
gives
"domain_selected": [
"test1.domain.tld",
"test3.domain.tld",
"test4.domain.tld"
]

how can i loop over a variable that might have single value?

I'm writing a playbook and want to loop a role over a variable that gets its value from the user. however that value might not always be a list of items, it might be a single value and whenever that happens it throws an error.
My Task:
- name: task name
include role:
name: role name
vars:
cluster_name: '{{ item }}'
loop: "{{ list_or_not }}"
loop_control:
loop_var: item
error:
...Invalid data passed to 'loop', it requires a list...
Have you tried the: "| list" filter?
Sorry cannot test at the moment.
You could test if the variable is a string, and if so, transform it into a single-item list. Something like this:
---
- hosts: localhost
gather_facts: false
tasks:
- set_fact:
list_or_not: ["{{ list_or_not }}"]
when: list_or_not is string
- debug:
msg: "{{ item }}"
loop: "{{ list_or_not }}"

Adding field to dict items

Consider the following play. What I am trying to do is add a field, tmp_path which is basically the key and revision appended together to each element in the scripts dict.
---
- hosts: localhost
connection: local
gather_facts: no
vars:
scripts:
a.pl:
revision: 123
b.pl:
revision: 456
tasks:
- with_dict: "{{ scripts }}"
debug:
msg: "{{ item.key }}_{{ item.value.revision }}"
# - with_items: "{{ scripts }}"
# set_fact: {{item.value.tmp_path}}="{{item.key}}_{{item.value.revision}}"
# - with_items: "{{ scripts }}"
# debug:
# msg: "{{ item.value.tmp_path }}"
...
Obviously the commented code doesn't work, any idea how I can get this working? Is it possible to alter the scripts dict directly, or should I somehow be creating a new dict to reference instead?
By the way welcome to correct the terminology for what I am trying to do.
OK, I think I got a solution (below), at least to let me move forwards with this. Disadvantages are it has removed the structure of my dict and also seems a bit redundant having to redefine all the fields and use a new variable, If anyone can provide a better solution I will accept that instead.
---
- hosts: localhost
connection: local
gather_facts: no
vars:
scripts:
a.pl:
revision: 123
b.pl:
revision: 456
tasks:
- with_dict: "{{ scripts }}"
debug:
msg: "{{ item.key }}_{{ item.value.revision }}"
- with_dict: "{{ scripts }}"
set_fact:
new_scripts: "{{ (new_scripts | default([])) + [ {'name': item.key, 'revision': item.value.revision, 'tmp_path': item.key ~ '_' ~ item.value.revision}] }}"
# - debug:
# var: x
# - with_dict: "{{ scripts }}"
- with_items: "{{ new_scripts }}"
debug:
msg: "{{ item.tmp_path }}"
...
BTW credit to the following question which pointed me in the right direction:
Using Ansible set_fact to create a dictionary from register results

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