How to filter element of list with a list in ansible with a json_query or other

Question

I created an ansible playbook. And I want a task executed only if a json_query returns element.

The json query have to returned an array searching if in an element from array of array exists in an element of another array.

I already tried using json_query (jmespath) with simplified queries I read the jmespath doc and try with the website tutorial. Read the ansible documentation and try to find example.

I think the good solution is to use contains built-in functions and map functions. But example with map and the documentation is not clear for me.

Example :

array_of_array_to_check : [
{
    hosts : ["host1", "host2"],
    name : "name1"
},
{
    hosts : [ "host3", "host1"],
    name : "name2"
},
{
    hosts : ["host4", "host5"],
    name : "name3"
}
]

array_parameters: ["host1", "host18"]

Expected :

result: [
{
    hosts: ["host1", "host2"],
    name: "name1"
},
{
    hosts: ["host3", "host1"],
    name: "name2"
}
]

Answer 1

here is a way to do it:

---
- hosts: localhost
  gather_facts: false
  vars:
    array_of_array_to_check:
    - hosts:
      - host1
      - host2
      name: name1
    - hosts:
      - host3
      - host1
      name: name2
    - hosts:
      - host4
      - host5
      name: name3
    array_parameters: 
    - host1
    - host18

  tasks:
  - name: parse array and add to results
    set_fact: 
      results_array: "{{ results_array | default([]) + [item] }}"
    when: item.hosts | intersect(array_parameters) | length > 0
    with_items:
    - "{{ array_of_array_to_check }}"

  - debug:
      var: results_array

basically you parse the array_of_array_to_check list, and if you find common elements in its elements' hosts list with the array_parameters, then you add the whole "item" to the results_array

intersect filter gets the "unique list of all items in both" , so if length is more than 0, then there are matches found.

hope it helps.