Replacing variables in external file through playbook - deployment

Question

I would like to use variables (vars.yaml) to replace the content in a config file (config.yaml) and automatise the process in the playbook (playbook.yaml). But I can't found a type of process that automaticly search for vars inside an external file through the playbook.yaml.
My files look like this :
vars.yaml
---
var1: content1
var2: content2
var3: content3
config.yaml:
apiVersion: 1
datasources:
- name: {{ var1 }}
type: {{ var2 }}
access: proxy
url: {{ var3 }}
playbook.yaml:
---
- name: Deploy
hosts: localhost
tasks:
- include_vars: ./vars.yaml
- name: Update config file
# Something to replace all vars in the config file using the content of vars.yaml
Can you help me and tell me if there is something possible instead of doing a regex for each variable ...?

Answer 1

The file with the unresolved variables is actually a template. Let's name it this way
shell> cat config.yaml.j2
apiVersion: 1
datasources:
- name: {{ var1 }}
type: {{ var2 }}
access: proxy
url: {{ var3 }}
Use the template module to update config.yaml, e.g.
- include_vars: vars.yaml
- name: Update config file
template:
src: config.yaml.j2
dest: config.yaml
gives
shell> cat config.yaml
apiVersion: 1
datasources:
- name: content1
type: content2
access: proxy
url: content3