Ansible Set Dynamic Environment Variables - bash

Question

I know about Ansible's environment: command at the top of playbook, but I don't think that will work for me seeing how I don't know the variables value prior to the execution of the playbook. I'm trying to retrieve package versions and PHP Modules and log them to a file. I want to use regex to capture the version and store it to an environment variable. Then I want to write that variable equals that variable's value to an environment file with a shell command. I also want to pull an array from the environment and loop through that. Ansible doesn't seem to persist the shell environment and the environment variable gets wiped out between commands. This is simple in Bash. Is this possible in Ansible? I'm trying:
---
- hosts: all
become: yes
vars:
site_variables:
code_directory: /home/
dependency_versions:
WGET_VERSION: placeholder
PHP_MODULES: placeholder
tasks:
- name: Retrieve Environment
shell: export WGET_VERSION=$(wget --version | grep -o 'Wget [0-9]*.[0-9]*\+')
shell: export PHP_MODULES=$(php -m)
shell: echo "export {{ item }}={{ lookup('env', item ) }}" >> {{ site_variables.code_directory }}/.env.log
with_items:
- WGET_VERSION
- name: Write PHP Modules Out
shell: export PHP_MODULES=$(php -m)
shell: export PHP_MODULES=$(echo {{ lookup('env', 'PHP_MODULES') }} | sed 's/\[PHP Modules\]//g')
shell: export PHP_MODULES=$(echo {{ lookup('env', 'PHP_MODULES') }} | sed 's/\[Zend Modules\]//g')
shell: export PHP_MODULES=({{ lookup('env', 'PHP_MODULES') }})
shell: echo "# - {{ item.0 }}" >> {{ site_variables.code_directory }}/.env.log
with_items:
- "{{ lookup('env', 'PHP_MODULES') }}"

Answer 1

There's a lot going on here.
First, lookup always runs on the ansible control host, while the script that you pass to the shell module is running on the remote server. So you will never be able to get a remote environment variable using lookup.
For details: https://docs.ansible.com/ansible/playbooks_lookups.html
Secondly, environment variables don't propagate from a child to parent. If you have a script that does this...
export MYVARIABLE=foo
...and you run that script, your current environment will not suddenly have a variable named MYVARIABLE. This is just as true for processes spawned by Ansible as it is for processes spawned by your shell.
If you want to set an ansible variable, consider using the register keyword to get the value:
- hosts: localhost
gather_facts: false
tasks:
- name: get wget version
command: wget --version
register: wget_version_raw
- name: extract wget version
set_fact:
wget_version: "{{ wget_version_raw.stdout_lines[0].split()[2] }}"
- name: show wget version
debug:
msg: "wget version is: {{ wget_version }}"