Render numbers inside an Ansible yaml template

Question

Very close to Create an int var with Ansible's ternary operator and that answer https://stackoverflow.com/a/69109779/446302

In an Ansible project, I'm trying to have a yaml template file with integer content like so:

---
my_service:
  enable_ipv6: false
  node_listen:
    - port: '{{ http_port | int }}'
      ip: '{{ srv_ip }}'

Unfortunately, it renders to:

---
my_service:
  enable_ipv6: false
  node_listen:
    - port: '8080'
      ip: '192.0.0.2'

The application I'm using is strict about port type, which means it crashes unless I can give it an int port number.

How can I cast it knowing that I need to keep it inside a template file, due to loops for other sub-settings?

Answer 1

For a Jinja2 Template file service.yml.j2 as input

---
my_service:
  enable_ipv6: false
  node_listen:
    - port: {{ HTTP_PORT }}
      ip: '{{ SRV_IP }}'

processing via a minimal example playbook main.yml

---
- hosts: localhost
  become: false
  gather_facts: false

  vars:

    HTTP_PORT: 8080
    SRV_IP: 127.0.0.1

  tasks:

  - template:
      src: service.yml.j2  #  input file
      dest: service.yml    # output file

will result into an output file service.yml with content of

---
my_service:
  enable_ipv6: false
  node_listen:
    - port: 8080
      ip: '127.0.0.1'