Add support for loopback type in nmcli module (#7515)

* add support for loopback devices

* add support for loopback devices

* fix yamllint issue in changelog fragment

* Fix yamlint warning and add note about new connectin type in docs

* change order of lines in documentation so they are sorted

changelogs/fragments/6572-nmcli-add-support-loopback-type.yml

@@ -0,0 +1,2 @@
+minor_changes:
+  - nmcli - add support for new connection type ``loopback`` (https://github.com/ansible-collections/community.general/issues/6572).

plugins/modules/nmcli.py

@@ -63,6 +63,7 @@ options:
             - Type V(generic) is added in Ansible 2.5.
             - Type V(infiniband) is added in community.general 2.0.0.
             - Type V(gsm) is added in community.general 3.7.0.
+            - Type V(loopback) is added in community.general 8.1.0.
             - Type V(macvlan) is added in community.general 6.6.0.
             - Type V(wireguard) is added in community.general 4.3.0.
             - Type V(vpn) is added in community.general 5.1.0.
@@ -70,7 +71,7 @@ options:
             - If you want to control non-ethernet connection attached to V(bond), V(bridge), or V(team) consider using O(slave_type) option.
         type: str
         choices: [ bond, bond-slave, bridge, bridge-slave, dummy, ethernet, generic, gre, infiniband, ipip, macvlan, sit, team, team-slave, vlan, vxlan,
-            wifi, gsm, wireguard, vpn ]
+            wifi, gsm, wireguard, vpn, loopback ]
     mode:
         description:
             - This is the type of device or network connection that you wish to create for a bond or bridge.
@@ -1938,6 +1939,7 @@ class Nmcli(object):
             'macvlan',
             'wireguard',
             'vpn',
+            'loopback',
         )
 
     @property
@@ -2421,6 +2423,7 @@ def main():
                           'macvlan',
                           'wireguard',
                           'vpn',
+                          'loopback',
                       ]),
             ip4=dict(type='list', elements='str'),
             gw4=dict(type='str'),

tests/unit/plugins/modules/test_nmcli.py

@@ -118,6 +118,12 @@ TESTCASE_CONNECTION = [
         'state': 'absent',
         '_ansible_check_mode': True,
     },
+    {
+        'type': 'loopback',
+        'conn_name': 'non_existent_nw_device',
+        'state': 'absent',
+        '_ansible_check_mode': True,
+    },
 ]
 
 TESTCASE_GENERIC = [
@@ -944,6 +950,28 @@ TESTCASE_ETHERNET_STATIC = [
     }
 ]
 
+TESTCASE_LOOPBACK = [
+    {
+        'type': 'loopback',
+        'conn_name': 'lo',
+        'ifname': 'lo',
+        'ip4': '127.0.0.1/8',
+        'state': 'present',
+        '_ansible_check_mode': False,
+    }
+]
+
+TESTCASE_LOOPBACK_MODIFY = [
+    {
+        'type': 'loopback',
+        'conn_name': 'lo',
+        'ifname': 'lo',
+        'ip4': ['127.0.0.1/8', '127.0.0.2/8'],
+        'state': 'present',
+        '_ansible_check_mode': False,
+    }
+]
+
 TESTCASE_ETHERNET_STATIC_SHOW_OUTPUT = """\
 connection.id:                          non_existent_nw_device
 connection.interface-name:              ethernet_non_existant
@@ -962,6 +990,21 @@ ipv6.ignore-auto-dns:                   no
 ipv6.ignore-auto-routes:                no
 """
 
+TESTCASE_LOOPBACK_SHOW_OUTPUT = """\
+connection.id:                          lo
+connection.interface-name:              lo
+connection.autoconnect:                 yes
+ipv4.method:                            manual
+ipv4.addresses:                         127.0.0.1/8
+ipv4.ignore-auto-dns:                   no
+ipv4.ignore-auto-routes:                no
+ipv4.never-default:                     no
+ipv4.may-fail:                          yes
+ipv6.method:                            manual
+ipv6.ignore-auto-dns:                   no
+ipv6.ignore-auto-routes:                no
+"""
+
 TESTCASE_ETHERNET_STATIC_MULTIPLE_IP4_ADDRESSES = [
     {
         'type': 'ethernet',
@@ -1946,6 +1989,24 @@ def mocked_generic_connection_diff_check(mocker):
                execute_return=(0, TESTCASE_GENERIC_SHOW_OUTPUT, ""))
 
 
+@pytest.fixture
+def mocked_loopback_connection_unchanged(mocker):
+    mocker_set(mocker,
+               connection_exists=True,
+               execute_return=(0, TESTCASE_LOOPBACK_SHOW_OUTPUT, ""))
+
+
+@pytest.fixture
+def mocked_loopback_connection_modify(mocker):
+    mocker_set(mocker,
+               connection_exists=True,
+               execute_return=None,
+               execute_side_effect=(
+                   (0, TESTCASE_LOOPBACK_SHOW_OUTPUT, ""),
+                   (0, "", ""),
+               ))
+
+
 @pytest.mark.parametrize('patch_ansible_module', TESTCASE_BOND, indirect=['patch_ansible_module'])
 def test_bond_connection_create(mocked_generic_connection_create, capfd):
     """
@@ -4712,3 +4773,75 @@ def test_slave_type_team_unchanged(mocked_create_slave_type_team_unchanged, capf
     results = json.loads(out)
     assert not results.get('failed')
     assert not results['changed']
+
+
+@pytest.mark.parametrize('patch_ansible_module', TESTCASE_LOOPBACK, indirect=['patch_ansible_module'])
+def test_create_loopback(mocked_generic_connection_create, capfd):
+    """
+    Test : Create loopback connection
+    """
+
+    with pytest.raises(SystemExit):
+        nmcli.main()
+
+    assert nmcli.Nmcli.execute_command.call_count == 1
+    arg_list = nmcli.Nmcli.execute_command.call_args_list
+    add_args, add_kw = arg_list[0]
+
+    assert add_args[0][0] == '/usr/bin/nmcli'
+    assert add_args[0][1] == 'con'
+    assert add_args[0][2] == 'add'
+    assert add_args[0][3] == 'type'
+    assert add_args[0][4] == 'loopback'
+    assert add_args[0][5] == 'con-name'
+    assert add_args[0][6] == 'lo'
+
+    add_args_text = list(map(to_text, add_args[0]))
+    for param in ['connection.interface-name', 'lo',
+                  'ipv4.addresses', '127.0.0.1/8']:
+        assert param in add_args_text
+
+    out, err = capfd.readouterr()
+    results = json.loads(out)
+    assert not results.get('failed')
+    assert results['changed']
+
+
+@pytest.mark.parametrize('patch_ansible_module', TESTCASE_LOOPBACK, indirect=['patch_ansible_module'])
+def test_unchanged_loopback(mocked_loopback_connection_unchanged, capfd):
+    """
+    Test : loopback connection unchanged
+    """
+    with pytest.raises(SystemExit):
+        nmcli.main()
+
+    out, err = capfd.readouterr()
+    results = json.loads(out)
+    assert not results.get('failed')
+    assert not results['changed']
+
+
+@pytest.mark.parametrize('patch_ansible_module', TESTCASE_LOOPBACK_MODIFY, indirect=['patch_ansible_module'])
+def test_add_second_ip4_address_to_loopback_connection(mocked_loopback_connection_modify, capfd):
+    """
+    Test : Modify loopback connection
+    """
+    with pytest.raises(SystemExit):
+        nmcli.main()
+
+    assert nmcli.Nmcli.execute_command.call_count == 2
+    arg_list = nmcli.Nmcli.execute_command.call_args_list
+    args, kwargs = arg_list[1]
+
+    assert args[0][0] == '/usr/bin/nmcli'
+    assert args[0][1] == 'con'
+    assert args[0][2] == 'modify'
+    assert args[0][3] == 'lo'
+
+    for param in ['ipv4.addresses', '127.0.0.1/8,127.0.0.2/8']:
+        assert param in args[0]
+
+    out, err = capfd.readouterr()
+    results = json.loads(out)
+    assert not results.get('failed')
+    assert results['changed']