merging dictionaries in ansible

Question

I\'m currently building a role for installing PHP using ansible, and I\'m having some difficulty merging dictionaries. I\'ve tried several ways to do so, but I can\'t get it

Answer 1

If you want hash merging I would turn the hash merging feature on in ansible. In your ansible config file turn hash merging on.

With hash_behaviour=merge you can have two var files with the same variable name:

defaults.yml:

values:
  key: value

overrides.yml:

values:
  my_key: my_value

In order for the two vars to be merged you will need to include both var files:

ansible-playbook some-play.yml ... -e@defaults.yml  -e@overrides.yml

And you will end up with this:

TASK: [debug var=values] ********************************************************
ok: [localhost] => {
    "values": {
        "key": value,
        "my_key": my_value
    }
}

Calling update on a variable can be done in Jinja but in general it will be messy, I wouldn't do it outside of your templates and even then try to avoid it altogether.