Ansible troubleshooting - Error 207: Jinja Invalid

Ansible Error 207, "`jinja[invalid]`", flags invalid Jinja2 templates like unexpected characters within double curly braces (e.g., {{ & }}).

Introduction

Ansible, the popular automation tool, leverages the power of Jinja2 templates to enable dynamic configurations, data manipulation, and conditional processing in playbooks. However, using Jinja2 templates effectively and correctly is essential to ensure that your Ansible playbooks run without errors. In this article, we’ll explore Ansible Error 207, “jinja[invalid]”, in [Ansible-Lint](/articles/ansible-lint) which focuses on the detection of invalid Jinja2 templates in your Ansible playbooks. We’ll discuss the importance of template validity and how adhering to best practices can help you avoid runtime errors and maintain the reliability of your automation tasks.

The Problem: Detecting Invalid Jinja2 Templates

Ansible Error 207, “jinja[invalid]”, is designed to identify invalid Jinja2 templates within your playbooks. Invalid templates, such as double curly braces within an expression (e.g., {{ {{ ‘1’ }} }}), can result in runtime errors if you attempt to use them with Ansible, even if they pass the Ansible syntax check.

Problematic Code Example:

``yaml


---
name: Example error 207
  hosts: all
  tasks:
    - name: Error 207
      ansible.builtin.debug:
      vars:
        bar: "{{ & }}" # <-- jinja[invalid]

In the problematic code above, the Jinja2 template contains an invalid expression that uses the ampersand symbol (&) without proper formatting within double curly braces.



Output:

`bash


WARNING  Could not parse missing filter name from error message: template error while templating string: unexpected char '&' at 3. String: {{ & }}. unexpected char '&' at 3
WARNING  Could not parse missing filter name from error message: template error while templating string: unexpected char '&' at 3. String: {{ & }}. unexpected char '&' at 3
WARNING  Listing 1 violation(s) that are fatal
jinja[invalid]: template error while templating string: unexpected char '&' at 3. String: {{ & }}. unexpected char '&' at 3
207.yml:8 Task/Handler: Error 207

Read documentation for instructions on how to ignore specific rule violations.

              Rule Violation Summary               
 count tag            profile rule associated tags 
     1 jinja[invalid] basic   formatting           

Failed: 1 failure(s), 0 warning(s) on 1 files. Last profile that met the validation criteria was 'min'.



Correcting Invalid Jinja2 Templates
To address Ansible Error 207 and ensure the validity of your Jinja2 templates, follow best practices for correct formatting. Here’s the corrected code:

`yaml


---
name: Example error 207
  hosts: all
  tasks:
    - name: Error 207
      ansible.builtin.debug:
      vars:
        bar: "{{ '&' }}"

In the corrected code, the Jinja2 template has been formatted correctly within double curly braces, ensuring its validity.

Benefits of Correcting Invalid Jinja2 Templates

1. Preventing Runtime Errors: Ensuring the validity of Jinja2 templates helps prevent runtime errors when you execute your