Ansible Plugins¶

docker exec ansible-controller sh -c "cd /labs-scripts && mkdir -p filter_plugins && cat > filter_plugins/custom_filters.py << 'EOF'
def mask_string(value, show_last=4, mask_char='*'):
    value = str(value)
    if len(value) <= show_last:
        return mask_char * len(value)
    return mask_char * (len(value) - show_last) + value[-show_last:]


def to_env_format(data, prefix=''):
    lines = []
    for key, value in data.items():
        env_key = (prefix.upper() + key.upper()).replace('-', '_')
        lines.append(f'{env_key}={value}')
    return '\n'.join(lines)


def extract_hostnames(host_list, separator=','):
    return separator.join(host_list)


class FilterModule(object):
    def filters(self):
        return {
            'mask_string': mask_string,
            'to_env_format': to_env_format,
            'extract_hostnames': extract_hostnames,
        }
EOF"

docker exec ansible-controller sh -c "cd /labs-scripts && cat > lab032-plugins.yml << 'EOF'
---
- name: Custom Plugins Practice
  hosts: localhost
  gather_facts: false

  vars:
    secret_key: \"AbCdEf123456!@#\"
    app_config:
      host: localhost
      port: \"5432\"
      database: mydb
      pool_size: \"10\"
    servers:
      - web1.example.com
      - web2.example.com
      - db1.example.com

  tasks:
    - name: Mask the secret key
      ansible.builtin.debug:
        msg: \"Secret key: {{ secret_key | mask_string }}\"

    - name: Convert config to env format
      ansible.builtin.debug:
        msg: \"{{ app_config | to_env_format('APP_') }}\"

    - name: Extract hostnames
      ansible.builtin.debug:
        msg: \"Servers: {{ servers | extract_hostnames }}\"

    - name: Built-in filter examples
      ansible.builtin.debug:
        msg:
          - \"Uppercase: {{ 'hello' | upper }}\"
          - \"Sorted: {{ [3,1,2] | sort }}\"
          - \"Default: {{ undefined_var | default('fallback') }}\"
EOF
ansible-playbook lab032-plugins.yml"

docker exec ansible-controller sh -c "cd /labs-scripts && mkdir -p callback_plugins && cat > callback_plugins/json_report.py << 'EOF'
from __future__ import absolute_import, division, print_function
__metaclass__ = type

import json
import datetime
from ansible.plugins.callback import CallbackBase

DOCUMENTATION = '''
  name: json_report
  short_description: Save JSON execution report
'''


class CallbackModule(CallbackBase):
    CALLBACK_VERSION = 2.0
    CALLBACK_TYPE = 'notification'
    CALLBACK_NAME = 'json_report'
    CALLBACK_NEEDS_ENABLED = True

    def __init__(self):
        super().__init__()
        self.report = {
            'start_time': datetime.datetime.now().isoformat(),
            'plays': [],
            'summary': {}
        }

    def v2_playbook_on_stats(self, stats):
        for host in stats.processed.keys():
            s = stats.summarize(host)
            self.report['summary'][host] = s
        self.report['end_time'] = datetime.datetime.now().isoformat()
        with open('/tmp/ansible-report.json', 'w') as f:
            json.dump(self.report, f, indent=2)
        self._display.display('JSON report saved to /tmp/ansible-report.json')
EOF"

# Enable the callback in ansible.cfg
docker exec ansible-controller sh -c "cd /labs-scripts && grep -q 'callbacks_enabled' ansible.cfg 2>/dev/null || echo '[defaults]
callbacks_enabled = json_report' >> ansible.cfg"

docker exec ansible-controller sh -c "cd /labs-scripts && ansible-playbook site.yml --check 2>/dev/null || ansible -m ping all"
docker exec ansible-controller sh -c "cat /tmp/ansible-report.json 2>/dev/null | python3 -m json.tool | head -30"

docker exec ansible-controller sh -c "cd /labs-scripts && mkdir -p lookup_plugins && cat > lookup_plugins/kv_config.py << 'EOF'
from __future__ import absolute_import, division, print_function
__metaclass__ = type

from ansible.plugins.lookup import LookupBase
from ansible.errors import AnsibleError

DOCUMENTATION = '''
  name: kv_config
  short_description: Read key=value config files
'''


class LookupModule(LookupBase):
    def run(self, terms, variables=None, **kwargs):
        results = []
        for term in terms:
            try:
                config = {}
                with open(term, 'r') as f:
                    for line in f:
                        line = line.strip()
                        if line and not line.startswith('#') and '=' in line:
                            key, value = line.split('=', 1)
                            config[key.strip()] = value.strip()
                results.append(config)
            except IOError as e:
                raise AnsibleError(f'Cannot read config file {term}: {e}')
        return results
EOF"

# Create a test config file and playbook
docker exec ansible-controller sh -c "cat > /tmp/app.cfg << 'EOF'
# Application configuration
app_name=myapp
app_port=8080
db_host=localhost
db_name=appdb
EOF"

docker exec ansible-controller sh -c "cd /labs-scripts && cat > lab032-lookup.yml << 'EOF'
---
- name: Custom Lookup Plugin Test
  hosts: localhost
  gather_facts: false

  tasks:
    - name: Load config using custom lookup
      ansible.builtin.set_fact:
        app_config: \"{{ lookup('kv_config', '/tmp/app.cfg') }}\"

    - name: Show loaded config
      ansible.builtin.debug:
        msg:
          - \"App: {{ app_config.app_name }}\"
          - \"Port: {{ app_config.app_port }}\"
          - \"DB: {{ app_config.db_host }}/{{ app_config.db_name }}\"
EOF
ansible-playbook lab032-lookup.yml"

docker exec ansible-controller sh -c "cd /labs-scripts && cat > lab032-vars-plugin-demo.yml << 'EOF'
---
# Demonstration of built-in host_group_vars plugin behavior
# The host_group_vars plugin is enabled by default and loads group_vars/ and host_vars/
- name: Vars Plugin Demo
  hosts: localhost
  gather_facts: false

  tasks:
    - name: Show which vars plugins are active
      ansible.builtin.command:
        cmd: ansible-doc -t vars -l
      register: vars_plugins
      changed_when: false

    - name: Display available vars plugins
      ansible.builtin.debug:
        var: vars_plugins.stdout_lines

    - name: Create a demo vars file loaded by host_group_vars
      ansible.builtin.copy:
        content: |
          # Loaded automatically by the host_group_vars plugin
          demo_plugin_var: \"loaded by vars plugin\"
          plugin_timestamp: \"{{ ansible_date_time.iso8601 | default('n/a') }}\"
        dest: /labs-scripts/group_vars/all/plugin_demo.yml
        mode: \"0644\"
      delegate_to: localhost
EOF
ansible-playbook lab032-vars-plugin-demo.yml"