[Banner] Added CLI commands to configure Banner and display current configuration (sonic-net#3021)

What I did
Added CLI commands for Banner feature according to HLD: sonic-net/SONiC#1361

How I did it
Added CLI commands to:

Enable/disable Banner feature
Configure Banner messages: login/motd/logout
Related show command
How to verify it
Manual testing

Author: SviatoslavBoichuk

config/main.py

@@ -8065,5 +8065,58 @@ def max_sessions(max_sessions):
                         {'max_sessions': max_sessions})
 
 
+#
+# 'banner' group ('config banner ...')
+#
+@config.group()
+def banner():
+    """Configuring system banner messages"""
+    pass
+
+
+@banner.command()
+@click.argument('state', metavar='<enabled|disabled>', required=True, type=click.Choice(['enabled', 'disabled']))
+def state(state):
+    """Set banner feature state"""
+
+    config_db = ConfigDBConnector()
+    config_db.connect()
+    config_db.mod_entry(swsscommon.CFG_BANNER_MESSAGE_TABLE_NAME, 'global',
+                        {'state': state})
+
+
+@banner.command()
+@click.argument('message', metavar='<message>', required=True)
+def login(message):
+    """Set login message"""
+
+    config_db = ConfigDBConnector()
+    config_db.connect()
+    config_db.mod_entry(swsscommon.CFG_BANNER_MESSAGE_TABLE_NAME, 'global',
+                        {'login': message})
+
+
+@banner.command()
+@click.argument('message', metavar='<message>', required=True)
+def logout(message):
+    """Set logout message"""
+
+    config_db = ConfigDBConnector()
+    config_db.connect()
+    config_db.mod_entry(swsscommon.CFG_BANNER_MESSAGE_TABLE_NAME, 'global',
+                        {'logout': message})
+
+
+@banner.command()
+@click.argument('message', metavar='<message>', required=True)
+def motd(message):
+    """Set message of the day"""
+
+    config_db = ConfigDBConnector()
+    config_db.connect()
+    config_db.mod_entry(swsscommon.CFG_BANNER_MESSAGE_TABLE_NAME, 'global',
+                        {'motd': message})
+
+
 if __name__ == '__main__':
     config()

doc/Command-Reference.md

@@ -225,6 +225,9 @@
   * [Static DNS show command](#static-dns-show-command)
 * [Wake-on-LAN Commands](#wake-on-lan-commands)
   * [Send Wake-on-LAN Magic Packet command](#send-wake-on-lan-magic-packet-command)
+* [Banner Commands](#banner-commands)
+  * [Banner config commands](#banner-config-commands)
+  * [Banner show command](#banner-show-command)
 
 ## Document History
 
@@ -13819,3 +13822,89 @@ Sending 3 magic packet to 11:33:55:77:99:bb via interface Vlan1000
 ```
 
 For the 4th example, it specifise 2 target MAC addresses and `count` is 3. So it'll send 6 magic packets in total.
+
+# Banner Commands
+
+This sub-section explains the list of the configuration options available for Banner feature.
+
+## Banner config commands
+
+- Set banner feature state
+
+```
+admin@sonic:~$ config banner state <enabled|disabled>
+Usage: config config banner state <enabled|disabled>
+
+  Set banner feature state
+
+Options:
+  -?, -h, --help  Show this message and exit.
+```
+
+- Set login message
+
+```
+admin@sonic:~$ config banner login <message>
+Usage: config banner login <message>
+
+  Set login message
+
+Options:
+  -?, -h, --help  Show this message and exit.
+```
+
+- Set logout message
+
+```
+admin@sonic:~$ config banner logout <message>
+Usage: config banner logout <message>
+
+  Set logout message
+
+Options:
+  -?, -h, --help  Show this message and exit.
+```
+
+- Set message of the day
+
+```
+admin@sonic:~$ config banner motd <message>
+Usage: config banner motd <message>
+
+  Set message of the day
+
+Options:
+  -?, -h, --help  Show this message and exit.
+```
+
+## Banner show command
+
+- how banner messages
+
+```
+admin@sonic:~$ show banner
+Usage: show banner
+
+  Show banner messages
+
+Options:
+  -h, -?, --help  Show this message and exit.
+```
+```
+admin@sonic:~$ show banner
+state    login    motd                                              logout
+-------  -------  ------------------------------------------------  --------
+enabled  Login    You are on
+         Message    ____   ___  _   _ _  ____
+                   / ___| / _ \| \ | (_)/ ___|
+                   \___ \| | | |  \| | | |
+                    ___) | |_| | |\  | | |___
+                   |____/ \___/|_| \_|_|\____|
+
+                  -- Software for Open Networking in the Cloud --
+
+                  Unauthorized access and/or use are prohibited.
+                  All access and/or use are subject to monitoring.
+
+                  Help:    https://sonic-net.github.io/SONiC/
+```

show/main.py

@@ -2616,6 +2616,26 @@ def ssh(db):
     click.echo(tabulate(configuration, headers=hdrs, tablefmt='simple', missingval=''))
 
 
+#
+# 'banner' command group ("show banner ...")
+#
+@cli.group('banner', invoke_without_command=True)
+@clicommon.pass_db
+def banner(db):
+    """Show banner messages"""
+
+    banner_table = db.cfgdb.get_entry('BANNER_MESSAGE', 'global')
+
+    hdrs = ['state', 'login', 'motd', 'logout']
+    data = []
+
+    for key in hdrs:
+        data.append(banner_table.get(key, '').replace('\\n', '\n'))
+
+    messages = [data]
+    click.echo(tabulate(messages, headers=hdrs, tablefmt='simple', missingval=''))
+
+
 # Load plugins and register them
 helper = util_base.UtilHelper()
 helper.load_and_register_plugins(plugins, cli)

tests/config_test.py

@@ -3905,3 +3905,63 @@ def teardown_class(cls):
         from .mock_tables import mock_single_asic
         importlib.reload(mock_single_asic)
         dbconnector.load_database_config()
+
+
+class TestConfigBanner(object):
+    @classmethod
+    def setup_class(cls):
+        print('SETUP')
+        import config.main
+        importlib.reload(config.main)
+
+    @patch('utilities_common.cli.run_command',
+           mock.MagicMock(side_effect=mock_run_command_side_effect))
+    def test_banner_state(self):
+        runner = CliRunner()
+        obj = {'db': Db().cfgdb}
+
+        result = runner.invoke(
+            config.config.commands['banner'].commands['state'],
+            ['enabled'], obj=obj)
+
+        assert result.exit_code == 0
+
+    @patch('utilities_common.cli.run_command',
+           mock.MagicMock(side_effect=mock_run_command_side_effect))
+    def test_banner_login(self):
+        runner = CliRunner()
+        obj = {'db': Db().cfgdb}
+
+        result = runner.invoke(
+            config.config.commands['banner'].commands['login'],
+            ['Login message'], obj=obj)
+
+        assert result.exit_code == 0
+
+    @patch('utilities_common.cli.run_command',
+           mock.MagicMock(side_effect=mock_run_command_side_effect))
+    def test_banner_logout(self):
+        runner = CliRunner()
+        obj = {'db': Db().cfgdb}
+
+        result = runner.invoke(
+            config.config.commands['banner'].commands['logout'],
+            ['Logout message'], obj=obj)
+
+        assert result.exit_code == 0
+
+    @patch('utilities_common.cli.run_command',
+           mock.MagicMock(side_effect=mock_run_command_side_effect))
+    def test_banner_motd(self):
+        runner = CliRunner()
+        obj = {'db': Db().cfgdb}
+
+        result = runner.invoke(
+            config.config.commands['banner'].commands['motd'],
+            ['Motd message'], obj=obj)
+
+        assert result.exit_code == 0
+
+    @classmethod
+    def teardown_class(cls):
+        print('TEARDOWN')

tests/show_test.py

@@ -1040,6 +1040,12 @@ def test_show_ztp(self, mock_run_command):
         assert result.exit_code == 0
         mock_run_command.assert_called_with(['ztp', 'status', '--verbose'], display_cmd=True)
 
+    @patch('show.main.run_command')
+    def test_show_banner(self, mock_run_command):
+        runner = CliRunner()
+        result = runner.invoke(show.cli.commands['banner'])
+        assert result.exit_code == 0
+
     def teardown(self):
         print('TEAR DOWN')