How to trigger a custom error from inside a Jinja template

ansiblecustom-errorsjinjatemplate

Though Ansible itself has a way for triggering a custom error, I can not find anything similar for Jinja.

My current method uses a syntax error:

{%  if 'ansible_mounts' in hostvars[host] %}
# {{ host }} knows its mount-points
{% else %}
# {% error!! No ansible_mounts listed for host - fact-gathering must've failed %}
{% endif %}

but those are rendered poorly at run-time — one needs to look inside the template-file and search for the error (the rendering does not even include the line-number!).

Is there a way to output a neat failure message from inside Jinja-template?

Best Answer

Answer from the comment:

There is no easy way to accomplish this – only via custom plugin. For details see: https://stackoverflow.com/questions/21778252/how-to-raise-an-exception-in-a-jinja2-macro

Related Solutions

Salt stack: use state jinja variables in template

You can pass any value you need to the template by using the defaults keyword. In your case, this would be:

{% for vpnuser in salt['pillar.get']('openvpn') %}
/etc/openvpn/ccd/{{ vpnuser }}:
  file.managed:
    - template: jinja
    - source: salt://openvpn/ccdtemplate
    - defaults:
        vpnuser: {{ vpnuser }}
{% endfor %}

This is documented in http://docs.saltstack.com/en/latest/ref/states/all/salt.states.file.html

How to pass item.src to a template in Ansible

Just reference them in the templates/sampletest.j2, for example:

# start of the template
classPath1 is {{ item.src[0].classPath1 }}
classPath2 is {{ item.src[1].classPath2 }}
contxtHost is {{ item.src[2].contxtHost }}
...
# end of the template

For each item on the List the template will be parsed and saved to a file defined in dest.

Now, the problem is that your vars/main.yml file defines src as a list (square brackets) of dictionaries, each containing a single key-value pair (with the key named differently in each item on the list), so:

first, you need to reference the list item by its order (e.g. src[1])
then, you need to reference the key which is defined in that particular item (e.g. classPath2 for and only for src[1]).

Best Answer

Related Solutions

Salt stack: use state jinja variables in template

How to pass item.src to a template in Ansible

Related Topic