Checking existence of an attribute value within a dictionary in Ansible

When you have to search within a list of dictionaries for the existence of a certain attribute value, you can use the 'selectattr' filter.

You specify the attribute you are interested in, the values this attribute is checked against, and after you convert to a list, you get the length. If the length is greater than zero, your list contains at least one item matching the criteria.


downlink_ports|selectattr('type','in','dslam,isam,lightspan')|list|length > 0

References:
https://jinja.palletsprojects.com/en/master/templates/#list-of-builtin-tests
http://www.oznetnerd.com/jinja2-selectattr-filter/