Ansible 2.4 check for match "word" in output - regex

Question

I would like to use ansible to check if a package name exist in an output of a command. if not exist do something.
for example :
I'm looking for the package "zip" but the problem is that it return "gzip" "zip" "unzip" and I'm looking to find only "zip" ,how to do it in a when condition
How can I use regex to match the {{ item.name }} exactly and not words that contains part of {{ item.name }}
- name: Check if Package is installed
shell: dpkg-query -f '${binary:Package}\n' -W
register: is_installed
- name: Install apt dependencies
apt:
name: "{{item.name}}{{item.version}}"
state: present
allow_unauthenticated: yes
force: yes
with_items:
- { name: 'python2.7', version: '' }
- { name: 'ruby', version: '' }
- { name: 'postgresql-9.5', version: '' }
- { name: 'postgresql-contrib-9.5', version: '' }
- { name: 'libpq-dev', version: '' }
- { name: 'nodejs', version: '=9.*' }
- { name: 'python-setuptools', version: '' }
- { name: 'python-pip', version: '' }
- { name: 'python-pkg-resources', version: '' }
- { name: 'sshpass', version: '' }
- { name: 'zip', version: '' }
- { name: 'mongodb-org', version: '=4.0.0' }
- { name: 'libfontconfig', version: '' }
- { name: 'ntp', version: '' }
- { name: 'fio', version: '' }
when: not "{{item.name}}" in is_installed.stdout

Answer 1

Am only partially able to test as don't have a Debian based machine in front of me.
You didn't update your Q to show the exact format of the output, so I am not sure if the command is outputting all the packages on a single line, or is outputting one per line.
If one per line, try this:
- name: Install apt dependencies
apt:
name: "{{item.name}}{{item.version}}"
state: present
allow_unauthenticated: yes
force: yes
with_items:
- { name: 'python2.7', version: '' }
- { name: 'ruby', version: '' }
when: not (is_installed.stdout_lines| map('regex_search', '^' + item.name + '$') | select('string') | list | length)
If on multiple lines, then is_installed.stdout_lines will be a list, with one package per item. Therefore we search the list for exact matches, and output the total count of matches. >0 = true.
If all on the same line, then try this instead:
- name: Install apt dependencies
apt:
name: "{{item.name}}{{item.version}}"
state: present
allow_unauthenticated: yes
force: yes
with_items:
- { name: 'python2.7', version: '' }
- { name: 'ruby', version: '' }
when: not (is_installed.stdout | search('(^| )' + item.name + '( |$)')
In this case, we need to search for the name either at the beginning of the line or preceded by a space, and then followed by a space or the end of the line, for an exact match.

Answer 2

Try modifying your regex like below
when: not (?<![\w\d]){{item.name}}(?![\w\d]) in is_installed.stdout