ansible lookup: issue in displaying as a list - ansible

I have a var file named prop.yml and contains:
var1:
- 'a'
- 'b'
var2:
- 'blah'
- 'blab'
Now, my playbook looks like:
task:
- name: including a variety file
include_vars:
file: prop.yml
name: property
- set_fact:
project: "{{ lookup ('vars', 'property') }}"
- debug:
msg: "{{ project }}"
Now, my output is
var1[
"a"
"b"]
var2[ "blah" , "blab"]
What I want as output is
["a", "b", "blah", "blab"]

Simply add the lists.
- debug:
msg: "{{ project.var1 + project.var2 }}"

The following should get you going:
task:
- name: including a variety file
include_vars:
file: prop.yml
name: property
- set_fact:
project: "{{ property.var1 + property.var2 }}"
- debug:
msg: "{{ project }}"
Rather than using the vars statically we can concatenate all lists in the included vars file by replacing the set_fact task with the following one.
This will only work if all declared vars in the file are all lists. Note the use of the default filter to make sure our result var is always defined. This also uses a loop over a dict
- name: Iteratively concatenate our lists
set_fact:
project: "{{ project | default([]) + item.value }}"
loop: "{{ property | dict2items }}"

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

Ansible - check variable type

Apparently, according to several hours of searching nobody has encountered this use-case:
Its simple - I would like to execute some ansible logic depending on variable type. Basically equivalent of e.g. instanceof(dict, var_name) but in Ansible:
- name: test
debug:
msg: "{{ instanceof(var_name, dict) | ternary('is a dictionary', 'is something else') }}"
Is there any way this can be done?
Q: "Execute some ansible logic depending on the variable type."
A: The tests including mapping work as expected. For example, the tasks below
- set_fact:
myvar:
key1: value1
- debug:
msg: "{{ (myvar is mapping)|
ternary('is a dictionary', 'is something else') }}"
give
msg: is a dictionary
Q: "Ansible - check variable type"
A: An option would be to discover the data type and dynamically include_tasks. For example, the tasks below
shell> cat tasks-int
- debug:
msg: Processing integer {{ item }}
shell> cat tasks-str
- debug:
msg: Processing string {{ item }}
shell> cat tasks-list
- debug:
msg: Processing list {{ item }}
shell> cat tasks-dict
- debug:
msg: Processing dictionary {{ item }}
with this playbook
- hosts: localhost
vars:
test:
- 123
- '123'
- [a,b,c]
- {key1: value1}
tasks:
- include_tasks: "tasks-{{ item|type_debug }}"
loop: "{{ test }}"
give (abridged)
msg: Processing integer 123
msg: Processing string 123
msg: Processing list ['a', 'b', 'c']
msg: 'Processing dictionary {''key1'': ''value1''}'
If you want to simulate the switch statement create a dictionary
case:
int: tasks-int
str: tasks-str
list: tasks-list
dict: tasks-dict
default: tasks-default
and use it in the include
- include_tasks: "{{ case[item|type_debug]|d(case.default) }}"
loop: "{{ test }}"
Since Ansible version 2.3 there is type_debug:
- name: test
debug:
msg: "{{ (( var_name | type_debug) == 'dict') | ternary('is a dictionary', 'is something else') }}"
Note that the docs state a preference for 'type tests'.
Older question, but you can do this easily with a Python custom filter plugin. Granted it would give you Python specific types, but that may be fine for your use case.
This could work. It just needs to be placed in a folder named filter_plugins alongside your playbook or role.
import sys
if sys.version_info[0] < 3:
raise Exception("Must be using Python 3")
def get_type(var, **kwargs):
return type(var)
class FilterModule(object):
def filters(self):
return {
"get_type": get_type
}
Then in your playbook:
- name: test
debug:
msg: "{{ var_name | get_type }}"

Ansible: Access facts set by set_fact

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: "{{ [] }}"

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

Ansible - How to keep appending new keys to a dictionary when using set_fact module with with_items?

I want to add keys to a dictionary when using set_fact with with_items. This is a small POC which will help me complete some other work. I have tried to generalize the POC so as to remove all the irrelevant details from it.
When I execute following code it is shows a dictionary with only one key that corresponds to the last item of the with_items. It seems that it is re-creating a new dictionary or may be overriding an existing dictionary for every item in the with_items. I want a single dictionary with all the keys.
Code:
---
- hosts: localhost
connection: local
vars:
some_value: 12345
dict: {}
tasks:
- set_fact: {
dict: "{
{{ item }}: {{ some_value }}
}"
}
with_items:
- 1
- 2
- 3
- debug: msg="{{ dict }}"
This can also be done without resorting to plugins, tested in Ansible 2.2.
---
- hosts: localhost
connection: local
vars:
some_value: 12345
dict: {}
tasks:
- set_fact:
dict: "{{ dict | combine( { item: some_value } ) }}"
with_items:
- 1
- 2
- 3
- debug: msg="{{ dict }}"
Alternatively, this can be written without the complex one-liner with an include file.
tasks:
- include: append_dict.yml
with_items: [1, 2, 3]
append_dict.yml:
- name: "Append dict: define helper variable"
set_fact:
_append_dict: "{ '{{ item }}': {{ some_value }} }"
- name: "Append dict: execute append"
set_fact:
dict: "{{ dict | combine( _append_dict ) }}"
Output:
TASK [debug]
*******************************************************************
ok: [localhost] => {
"msg": {
"1": "12345",
"2": "12345",
"3": "12345"
}
}
Single quotes ' around {{ some_value }} are needed to store string values explicitly.
This syntax can also be used to append from a dict elementwise using with_dict by referring to item.key and item.value.
Manipulations like adding pre- and postfixes or hashes can be performed in the same step, for example
set_fact:
dict: "{{ dict | combine( { item.key + key_postfix: item.value + '_' + item.value | hash('md5') } ) }}"
Use a filter plugin.
First, make a new file in your ansible base dir called filter_plugins/makedict.py.
Now create a new function called "makedict" (or whatever you want) that takes a value and a list and returns a new dictionary where the keys are the elements of the list and the value is always the same.
class FilterModule(object):
def filters(self):
return { 'makedict': lambda _val, _list: { k: _val for k in _list } }
Now you can use the new filter in the playbook to achieve your desired result:
- hosts: 127.0.0.1
connection: local
vars:
my_value: 12345
my_keys: [1, 2, 3]
tasks:
- set_fact: my_dict="{{ my_value | makedict(my_keys) }}"
- debug: msg="{{ item.key }}={{ item.value }}"
with_dict: "{{my_dict}}"
You can customize the location of the filter plugin using the filter_plugins option in ansible.cfg.
this does not seems to work any more on ansible 2.5
---
- hosts: localhost
connection: local
vars:
some_value: 12345
dict: {}
tasks:
- set_fact:
dict: "{{ dict | combine( { item: some_value } ) }}"
with_items:
- 1
- 2
- 3
- debug: msg="{{ dict }}"
returns only last value {"dict":{"3": "some value"}}
I suggest you could do this :
- set_fact:
__dict: |
{% for item in [1,2,3] %}
{{item}}: "value"
{% endfor %}
- set_fact:
final_dict: "{{__dict|from_yaml}}"
- debug:
var: final_dict
Another solution could be this one, tested in Ansible 2.9.6.
This solutions adds the extra benefit that you do not have to declare _dict beforehand in vars section. This is achieved by the | default({}) pipe which ensures that the loop will not fail in the first iteration when _dict is empty.
In addition, the renaming of dict to _dict is necessary since the dict is a special keyword reserved for <class 'dict'>. Referenced (unfortunately only at devel branch yet) here.
---
- hosts: localhost
connection: local
vars:
some_value: 12345
tasks:
- set_fact:
_dict: "{{ _dict | default({}) | combine( { item: some_value } ) }}"
with_items:
- 1
- 2
- 3
- debug: msg="{{ _dict }}"

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