Ansible module to read or generate a WireGuard keypair

wg_key

#!/usr/bin/python

EXAMPLES = '''
# Reads or generates a wireguard key
- wg_key: path=/etc/wireguard/site/secret.conf
'''

from ansible.module_utils.basic import AnsibleModule
import os
import re
import subprocess

if __name__ == '__main__':
  module = AnsibleModule(
    argument_spec={
      'path': {'required': True, 'type': 'str'},
    }
  )

  path    = module.params['path']
  pattern = re.compile(r'^PrivateKey\s*=\s*(\S+)')
  facts   = None
  privkey = None

  if os.path.isfile(path):
    # Extract private key
    for line in open(path):
        m = re.match(pattern, line)
        if m:
          privkey = m.group(1).encode()
          break
  else:
    # Generate private key
    privkey = subprocess.check_output(["wg", "genkey"]).strip()

  if privkey:
    facts = {
      "wg_privkey": privkey,
      # Derive public key from private key
      "wg_pubkey": subprocess.check_output(["wg", "pubkey"], input=privkey).strip(),
    }
    module.exit_json(ansible_facts=facts)
  else:
    module.fail_json(msg="Unable to find/generate wireguard key")