Problems trying to extract username and password from configuration file using a regular expression pattern

Question

I would need to extract an username and a password from a configuration file.

define( 'DB_USER', 'username' );
define( 'DB_PASSWORD', 'password' );

So far I managed to extract a string, using this code:

- set_fact:
    dbuser: "{{ wpconfig.stdout | regex_search('DB_USER(.+)', '\\1') | first }}"

Output

ok: [prod_server] => {
    "dbuser": "', 'username' );"
}

I would need to extract only the username part and get rid of all other characters.

I tried to play a bit with regular expressions, and I managed to build up one that apparently extracts the username part putting it into Group 1: https://regex101.com/r/OzJR1X/2

If I try to add it to my code, an error shows up:

Syntax Error while loading YAML.
  found unknown escape character 's'

Answer 1

Create a dictionary of the parameters. Given the list of the lines, e.g.

    - set_fact:
        wpconfig_list: "{{ lookup('file', 'wpconfig.conf').splitlines() }}"

  wpconfig_list:
  - define( 'DB_USER', 'username' );
  - define( 'DB_PASSWORD', 'password' );

---

Fit the code to your needs potentially using wpconfig.stdout_lines

---

The task creates the dictionary

    - set_fact:
        wpconfig_dict: "{{ wpconfig_dict|default({})|
                           combine({_key: _val}) }}"
      loop: "{{ wpconfig_list }}"
      vars:
        _regex1: '^.*\((.*),(.*)\).*$'
        _regex2: "'"
        _key: "{{ item|regex_replace(_regex1, '\\1')|trim|
                       regex_replace(_regex2, '') }}" 
        _val: "{{ item|regex_replace(_regex1, '\\2')|trim|
                       regex_replace(_regex2, '') }}"

  wpconfig_dict:
    DB_PASSWORD: password
    DB_USER: username

Select the user, e.g.

    - set_fact:
        dbuser: "{{ wpconfig_dict.DB_USER }}"

gives

  dbuser: username