How to write tick marks and brackets with Ansible 'lineinfile' module?

I am trying to write the following string with Ansible lininfile.

The failing Ansible task:

- name: Insert GetInterfaceIP
  lineinfile:
    path: /etc/consul.d/consul.hcl
    regexp: '^advertise'
    line: advertise_addr = "{{ GetInterfaceIP `eth0` }}"

Desired result in the file:

advertise_addr = "{{ GetInterfaceIP `eth0` }}"

How can I escape the special characters so that the line is written to the file exactly like this?

Solution

To prevent the given string from Templating, you might take advantage from Unsafe or raw strings.

The following example will add the exact string into the file

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

  tasks:

  - name: Add unsafe text line
    lineinfile:
      path: test.txt
      line: !unsafe 'advertise_addr = "{{ GetInterfaceIP `eth0` }}"'

resulting into an output of

tail -1 test.txt
advertise_addr = "{{ GetInterfaceIP `eth0` }}"

since

Marking data as unsafe prevents malicious users from abusing Jinja2 templates to execute arbitrary code on target machines. The Ansible implementation ensures that unsafe values are never templated.

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