Refactor openvswitch_db module (#23288)

The openvswitch_db module uses the ovs-vsctl binary to
address changes.
On other network modules we follow the pattern of returning 'commands'
as part of the result, containing the commands run on the target device.
Follow that for code consistency and maintenance.
Also, adding state param, which allows to add/remove keys on columns.

lib/ansible/modules/network/ovs/openvswitch_db.py

@@ -38,6 +38,16 @@ requirements: [ "ovs-vsctl >= 2.3.3" ]
 description:
     - Set column values in record in database table.
 options:
+    state:
+        required: false
+        description:
+            - Configures the state of the key. When set
+              to I(present), the I(key) and I(value) pair will be set
+              on the I(record) and when set to I(absent) the I(key)
+              will not be set.
+        default: present
+        choices: ['present', 'absent']
+        version_added: "2.4"
     table:
         required: true
         description:
@@ -82,58 +92,114 @@ EXAMPLES = '''
     col: other_config
     key: disable-in-band
     value: true
+
+# Remove in band key
+- openvswitch_db:
+    state: present
+    table: Bridge
+    record: br-int
+    col: other_config
+    key: disable-in-band
 '''
 
 
-def cmd_run(module, cmd, check_rc=True):
+def map_obj_to_command(want, have, module):
-    """ Log and run ovs-vsctl command. """
+    """ Define ovs-vsctl command to meet desired state """
-    return module.run_command(cmd.split(" "), check_rc=check_rc)
+    command = None
+
+    if module.params['state'] == 'absent':
+        if 'key' in have.keys():
+            templatized_command = "%(ovs-vsctl)s -t %(timeout)s remove %(table)s %(record)s " \
+                                  "%(col)s %(key)s=%(value)s"
+            command = templatized_command % module.params
+    else:
+        if 'key' not in have.keys():
+            templatized_command = "%(ovs-vsctl)s -t %(timeout)s add %(table)s %(record)s " \
+                                  "%(col)s %(key)s=%(value)s"
+            command = templatized_command % module.params
+        elif want['value'] != have['value']:
+            templatized_command = "%(ovs-vsctl)s -t %(timeout)s set %(table)s %(record)s " \
+                                  "%(col)s:%(key)s=%(value)s"
+            command = templatized_command % module.params
+
+    return command
 
 
-def params_set(module):
+def map_config_to_obj(module):
-    """ Implement the ovs-vsctl set commands. """
+    templatized_command = "%(ovs-vsctl)s -t %(timeout)s list %(table)s %(record)s"
+    command = templatized_command % module.params
+    rc, out, err = module.run_command(command, check_rc=True)
 
-    changed = False
+    if rc != 0:
+        module.fail_json(msg=err)
 
-    ##
+    match = re.search(r'^' + module.params['col'] + r'(\s+):(\s+)(.*)$', out, re.M)
-    # Place in params dictionary in order to support the string format below.
-    module.params["ovs-vsctl"] = module.get_bin_path("ovs-vsctl", True)
 
-    fmt = "%(ovs-vsctl)s -t %(timeout)s get %(table)s %(record)s " \
+    col_value = match.group(3)
-          "%(col)s:%(key)s"
+    col_value_to_dict = {}
+    if match.group(3):
+        for kv in col_value[1:-1].split(','):
+            k, v = kv.split('=')
+            col_value_to_dict[k.strip()] = v.strip()
 
-    cmd = fmt % module.params
+    obj = {
+        'table': module.params['table'],
+        'record': module.params['record'],
+        'col': module.params['col'],
+    }
 
-    (_, output, _) = cmd_run(module, cmd, False)
+    if module.params['key'] in col_value_to_dict:
-    if module.params['value'] not in output:
+        obj['key'] = module.params['key']
-        fmt = "%(ovs-vsctl)s -t %(timeout)s set %(table)s %(record)s " \
+        obj['value'] = col_value_to_dict[module.params['key']]
-              "%(col)s:%(key)s=%(value)s"
+
-        cmd = fmt % module.params
+    return obj
-        ##
+
-        # Check if flow exists and is the same.
+
-        (rtc, _, err) = cmd_run(module, cmd)
+def map_params_to_obj(module):
-        if rtc != 0:
+    obj = {
-            module.fail_json(msg=err)
+        'table': module.params['table'],
-        changed = True
+        'record': module.params['record'],
-    module.exit_json(changed=changed)
+        'col': module.params['col'],
+        'key': module.params['key'],
+        'value': module.params['value']
+    }
+
+    return obj
 
 
 # pylint: disable=E0602
 def main():
     """ Entry point for ansible module. """
-    module = AnsibleModule(
+    argument_spec = {
-        argument_spec={
+        'state': {'default': 'present', 'choices': ['present', 'absent']},
-            'table': {'required': True},
+        'table': {'required': True},
-            'record': {'required': True},
+        'record': {'required': True},
-            'col': {'required': True},
+        'col': {'required': True},
-            'key': {'required': True},
+        'key': {'required': True},
-            'value': {'required': True},
+        'value': {'required': True},
-            'timeout': {'default': 5, 'type': 'int'},
+        'timeout': {'default': 5, 'type': 'int'},
-        },
+    }
-        supports_check_mode=True,
-    )
 
-    params_set(module)
+    module = AnsibleModule(argument_spec=argument_spec,
+                           supports_check_mode=True)
+
+    result = {'changed': False}
+
+    # We add ovs-vsctl to module_params to later build up templatized commands
+    module.params["ovs-vsctl"] = module.get_bin_path("ovs-vsctl", True)
+
+    want = map_params_to_obj(module)
+    have = map_config_to_obj(module)
+
+    command = map_obj_to_command(want, have, module)
+    result['command'] = command
+
+    if command:
+        if not module.check_mode:
+            module.run_command(command, check_rc=True)
+        result['changed'] = True
+
+    module.exit_json(**result)
 
 
 # pylint: disable=W0614
@@ -142,6 +208,7 @@ def main():
 
 # import module snippets
 from ansible.module_utils.basic import *
+import re
 
 if __name__ == '__main__':
     main()