I need to create new variable from contents of other variables. Currently I'm using something like this:
- command: echo "{{ var1 }}-{{ var2 }}-{{ var3 }}" register: newvar The problem is:
- Usage of
{{ var1 }}...{{ varN }}brings too long strings and very ugly code. - Usage of
{{ newvar.stdout }}a bit better but confusing. - Usage of
set_factmodule caches fact between runs. It isn't appropriate for me.
Is there any other solution?
3 Answers
Since strings are lists of characters in Python, we can concatenate strings the same way we concatenate lists (with the + sign):
{{ var1 + '-' + var2 + '-' + var3 }} If you want to pipe the resulting string to some filter, make sure you enclose the bits in parentheses:
e.g. To concatenate our 3 vars, and get a sha512 hash:
{{ (var1 + var2 + var3) | hash('sha512') }} Note: this works on Ansible 2.3. I haven't tested it on earlier versions.
1Good question. But I think there is no good answer which fits your criteria. The best I can think of is to use an extra vars file.
A task like this:
- include_vars: concat.yml And in concat.yml you have your definition:
newvar: "{{ var1 }}-{{ var2 }}-{{ var3 }}" As simple as joining lists in python itself.
ansible -m debug -a msg="{{ '-'.join(('list', 'joined', 'together')) }}" localhost localhost | SUCCESS => { "msg": "list-joined-together" } Works the same way using variables:
ansible -m debug -a msg="{{ '-'.join((var1, var2, var3)) }}" localhost 
