在Ansible剧本中创建和访问字典

Question

I'm trying to set a variable in an Ansible playbook based on an existing variable's value which could be one of many different strings. It's basically a case/switch statement and this is the logic (with incorrect syntax):

if {{ existing_ansible_var }} == "string1"
  new_ansible_var = "a"
else if {{ existing_ansible_var }} == "string2"
  new_ansible_var = "b"
<...>
else
  new_ansible_var = ""

I can use a pretty slick technique with a dictionary that looks like this in Jinja:

{% set new_ansible_var = {"string1": "a", "string2": "b"}[existing_ansible_var] | default("") -%}

Can I use a similar dictionary construct to set a variable ( set_fact ) in a playbook?

Answer 1

As described in the other question/answer , you can do it like this:

vars: 
   myDict: {"string1": "a", "string2": "b"}
   new_ansible_var: '{{myDict[existing_ansible_var | default("this key does not exist in the dict")] | default("") }}'