Document testinfra vars management

Issue Type

• Feature request

Molecule and Ansible details

ansible --version && molecule --version

ansible 2.7.6
  config file = /home/ben/.ansible.cfg
  configured module search path = [u'/home/ben/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /home/ben/venv_ansible-2.7.6/local/lib/python2.7/site-packages/ansible
  executable location = /home/ben/venv_ansible-2.7.6/bin/ansible
  python version = 2.7.15rc1 (default, Nov 12 2018, 14:31:15) [GCC 7.3.0]
molecule, version 2.19.0

Molecule installation method (one of):

• pip

Ansible installation method (one of):

• pip

Desired Behavior

Warning: this could be considered two issues/features.

1. When working with the provisioner section of molecule.yml for a scenario and feeding TestInfra tests, I notice that I have to violate DRY and explicitly define the values of role variables (e.g. those defined within defaults/main.yml) within the provisioner.inventory.group_vars/host_vars section of molecule.yml for the values to be picked up within TestInfra tests.

2. Moreover, when defining the values of these vars within molecule.yml, I cannot reference the values of other variables using the "{{ }}" Ansible syntax. The double-curly braces seem to be interpreted as string literals and the value is not being substituted.

Examples:

1. Given defaults/main.yml has the following:

win_mssql_instances:
  - instance_name: MSSQLSERVER
    features: SQLENGINE
    instance_collation: SQL_Latin1_General_CP1_CI_AS
    sysadmins:
      - "{{ inventory_hostname_short[:15] }}\\{{ ansible_user }}"
    sqlusers:
      - "{{ inventory_hostname_short[:15] }}\\{{ ansible_user }}"
    setupadmins:
      - "{{ inventory_hostname_short[:15] }}\\{{ ansible_user }}"
    svcaccount: "{{ inventory_hostname_short[:15] }}\\{{ ansible_user }}"
    svcpassword: "{{ ansible_password }}"
    instance_dir: C:\Program Files\Microsoft SQL Server
    installdb_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
    userldb_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
    userdblog_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
    tempdb_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
    tempdblog_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
    backup_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Backup
    databases:
      - mssql_db

If my molecule.yml does NOT also define this, then my TestInfra test:

def test_installed(host):
    """
    Checks that the package is installed
    :param host: instance under test
    :return: None
    """

    # get variables defined in molecule.yml inventory
    ansible_vars = host.ansible.get_variables()
    instances = ansible_vars["win_mssql_instances"]

    for inst in instances:
        path = inst["instance_dir"]
        ansible_args = "path='" + path + "' state=file"

        assert host.ansible("win_file",
                            ansible_args)["changed"] is False

Fails with:

$ molecule verify

>       instances = ansible_vars["win_mssql_instances"]
E       KeyError: 'win_mssql_instances'

However, if I do something like this (repeat myself) in my molecule.yml:

provisioner:
  name: ansible
  inventory:
    group_vars:
      mssql:
        win_mssql_instances:
          - instance_name: MSSQLSERVER
            features: SQLENGINE
            instance_collation: SQL_Latin1_General_CP1_CI_AS
            sysadmins:
              - "{{ inventory_hostname_short[:15] }}\\{{ ansible_user }}"
            sqlusers:
              - "{{ inventory_hostname_short[:15] }}\\{{ ansible_user }}"
            setupadmins:
              - "{{ inventory_hostname_short[:15] }}\\{{ ansible_user }}"
            svcaccount: "{{ inventory_hostname_short[:15] }}\\{{ ansible_user }}"
            svcpassword: "{{ ansible_password }}"
            instance_dir: C:\Program Files\Microsoft SQL Server
            installdb_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
            userldb_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
            userdblog_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
            tempdb_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
            tempdblog_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Data
            backup_path: C:\Program Files\Microsoft SQL Server\MSSQLSERVER\MSSQL\Backup
            databases:
              - mssql_db

Then it works as expected:

$ molecule verify

Verifier completed successfully.

1. Given that I seem to have to do this (repeat myself) for role verification, then I often run into item/issue 2 where I cannot use the double-curly brace notation to reference Ansible magic vars or other vars within the role construct. This is again in relation to molecule verify and NOT molecule converge.

For example:

Given my molecule.yml contains:

provisioner:
  name: ansible
  inventory:
    group_vars:
      mssql:
        win_mssql_tmpdir: "C:\\TEMP\\Microsoft"
        win_mssql_extract_to: "{{ win_mssql_tmpdir}}\\MSSQL"
        win_mssql_extracts_path: "{{ win_mssql_extract_to }}\\Enterprise_Edition_x64\\setup.exe"

And my TestInfra test looks like:

def test_installer_extracted(host):
    """
    Checks that the installer is extracted
    :param host: instance under test
    :return: None
    """

    # get variables defined in molecule.yml inventory
    ansible_vars = host.ansible.get_variables()
    path = ansible_vars["win_mssql_extracts_path"]

    ansible_args = "path='" + path + "' state=file"

    assert host.ansible("win_file",
                        ansible_args)["changed"] is False

You can see the double-curly braces coming through seemingly as a string literal in the informational output:

INFO:testinfra:RUN Ansible('win_file', u"path='{{ win_mssql_extract_to }}\\Enterprise_Edition_x64\\setup.exe' state=file", {'check': True}): {'_ansible_no_log': False, '_ansible_parsed': True, u'changed': False}
tests/test_default.py::test_installer_extracted[ansible://knemol-ar-win-mssql-benlocal.kiewittest.com] PASSED

What’s more concerning, it is not properly reporting changed and the test is passing. If I hard-code an invalid file path (like I think I should):

provisioner:
  name: ansible
  inventory:
    group_vars:
      mssql:
        win_mssql_extracts_path: "C:\\fubar\\setup.exe"

I see an error that is apparently swallowed resulting in a passed test:

INFO:testinfra:RUN Ansible('win_file', u"path='C:\\fubar\\setup.exe' state=file", {'check': True}): {'_ansible_no_log': False,
 '_ansible_parsed': True,
 u'changed': False,
 u'msg': u"Get-AnsibleParam: Parameter 'path' has an invalid path 'C:\x0cubar\\setup.exe' specified."}
tests/test_default.py::test_installer_extracted[ansible://knemol-ar-win-mssql-benlocal.kiewittest.com] PASSED

But if I hard-code the path to handle the backslashes correctly for TestInfra:

provisioner:
  name: ansible
  inventory:
    group_vars:
      mssql:
        win_mssql_extracts_path: "C:\\\\fubar\\\\setup.exe"

I get this:

INFO:testinfra:RUN Ansible('win_file', u"path='C:\\\\fubar\\\\setup.exe' state=file", {'check': True}): {'_ansible_no_log': False,
 '_ansible_parsed': True,
 u'changed': False,
 u'msg': u'path C:\\fubar\\setup.exe will not be created'}
    tests/test_default.py::test_installer_extracted[ansible://knemol-ar-win-mssql-benlocal.kiewittest.com] PASSED

These appear to be TestInfra issues and/or Molecule feeding TestInfra, and they could be specific to my Windows-based roles under test, I’m not sure. I know there is a discussion about Molecule Verification in general (e.g. using a verify.yml Ansible playbook to do it). I kind of prefer the notion of a separate tool verifying Ansible rather than using Ansible to verify itself (this recent Boeing/FAA thing comes to mind).

Anyhow, my primary request is the whole not having to repeat yourself in molecule.yml, but we’ll see how this shakes out pending future verification discussions.

[1efty]

I found myself in this situation as well. You can create a pytest fixture to limit repetition.

@pytest.fixture(scope='module')
def AnsibleRoleDefaults(host):
  return host.ansible(
    'include_vars', '../../defaults/main.yml'
  }['ansible_facts']

def test_thing(host, AnsibleRoleDefaults):
  var = AnsibleRoleDefaults['var']
  var2 = host.ansible.get_variables()['var']

Due to the way testifnra creates the host fixture, using include_vars will work like it does within a play. So for some cases you might want to use debug msg={{ lookup('template','../../vars/main.yml') | from_yaml }}" this will get you the variables without bothering the variable space.

---

Would it be out of scope for molecule to provide these?

[RebelCodeBase]

Here is a pytest plugin that exposes ansible variables and facts, gopass secrets and the ansible python api as pytest fixtures in testinfra tests for molecule: testaid