[show] Break some groups out into their own modules (sonic-net#1259)

In order to organize code better, reduce the size of large files and help granularize unit test coverage reports, break out the following groups from show/main.py into their own files:

- acl
- dropcounters
- gearbox
- kdump
- nat
- platform
- processes
- sflow
- vnet
- vxlan
- warm_restart

Also remove the following check from utilities_common/cli.py:run_command() and fix all tests which relied upon it:

```
if os.getenv("UTILITIES_UNIT_TESTING") == "1":
        return
```

show/acl.py

@@ -0,0 +1,44 @@
+import click
+import utilities_common.cli as clicommon
+
+
+#
+# 'acl' group ###
+#
+
+@click.group(cls=clicommon.AliasedGroup)
+def acl():
+    """Show ACL related information"""
+    pass
+
+
+# 'rule' subcommand  ("show acl rule")
+@acl.command()
+@click.argument('table_name', required=False)
+@click.argument('rule_id', required=False)
+@click.option('--verbose', is_flag=True, help="Enable verbose output")
+def rule(table_name, rule_id, verbose):
+    """Show existing ACL rules"""
+    cmd = "acl-loader show rule"
+
+    if table_name is not None:
+        cmd += " {}".format(table_name)
+
+    if rule_id is not None:
+        cmd += " {}".format(rule_id)
+
+    clicommon.run_command(cmd, display_cmd=verbose)
+
+
+# 'table' subcommand  ("show acl table")
+@acl.command()
+@click.argument('table_name', required=False)
+@click.option('--verbose', is_flag=True, help="Enable verbose output")
+def table(table_name, verbose):
+    """Show existing ACL tables"""
+    cmd = "acl-loader show table"
+
+    if table_name is not None:
+        cmd += " {}".format(table_name)
+
+    clicommon.run_command(cmd, display_cmd=verbose)

show/dropcounters.py

@@ -0,0 +1,54 @@
+import click
+import utilities_common.cli as clicommon
+
+
+#
+# 'dropcounters' group ###
+#
+
+@click.group(cls=clicommon.AliasedGroup)
+def dropcounters():
+    """Show drop counter related information"""
+    pass
+
+
+# 'configuration' subcommand ("show dropcounters configuration")
+@dropcounters.command()
+@click.option('-g', '--group', required=False)
+@click.option('--verbose', is_flag=True, help="Enable verbose output")
+def configuration(group, verbose):
+    """Show current drop counter configuration"""
+    cmd = "dropconfig -c show_config"
+
+    if group:
+        cmd += " -g '{}'".format(group)
+
+    clicommon.run_command(cmd, display_cmd=verbose)
+
+
+# 'capabilities' subcommand ("show dropcounters capabilities")
+@dropcounters.command()
+@click.option('--verbose', is_flag=True, help="Enable verbose output")
+def capabilities(verbose):
+    """Show device drop counter capabilities"""
+    cmd = "dropconfig -c show_capabilities"
+
+    clicommon.run_command(cmd, display_cmd=verbose)
+
+
+# 'counts' subcommand ("show dropcounters counts")
+@dropcounters.command()
+@click.option('-g', '--group', required=False)
+@click.option('-t', '--counter_type', required=False)
+@click.option('--verbose', is_flag=True, help="Enable verbose output")
+def counts(group, counter_type, verbose):
+    """Show drop counts"""
+    cmd = "dropstat -c show"
+
+    if group:
+        cmd += " -g '{}'".format(group)
+
+    if counter_type:
+        cmd += " -t '{}'".format(counter_type)
+
+    clicommon.run_command(cmd, display_cmd=verbose)

show/gearbox.py

@@ -0,0 +1,34 @@
+import click
+import utilities_common.cli as clicommon
+
+
+@click.group(cls=clicommon.AliasedGroup)
+def gearbox():
+    """Show gearbox info"""
+    pass
+
+# 'phys' subcommand ("show gearbox phys")
+@gearbox.group(cls=clicommon.AliasedGroup)
+def phys():
+    """Show external PHY information"""
+    pass
+
+# 'status' subcommand ("show gearbox phys status")
+@phys.command()
+@click.pass_context
+def status(ctx):
+    """Show gearbox phys status"""
+    clicommon.run_command("gearboxutil phys status")
+
+# 'interfaces' subcommand ("show gearbox interfaces")
+@gearbox.group(cls=clicommon.AliasedGroup)
+def interfaces():
+    """Show gearbox interfaces information"""
+    pass
+
+# 'status' subcommand ("show gearbox interfaces status")
+@interfaces.command()
+@click.pass_context
+def status(ctx):
+    """Show gearbox interfaces status"""
+    clicommon.run_command("gearboxutil interfaces status")

show/kdump.py

@@ -0,0 +1,93 @@
+import click
+import utilities_common.cli as clicommon
+from swsssdk import ConfigDBConnector
+
+
+#
+# 'kdump command ("show kdump ...")
+#
+@click.group(cls=clicommon.AliasedGroup)
+def kdump():
+    """Show kdump configuration, status and information """
+    pass
+
+
+@kdump.command('enabled')
+def enabled():
+    """Show if kdump is enabled or disabled"""
+    kdump_is_enabled = False
+    config_db = ConfigDBConnector()
+    if config_db is not None:
+        config_db.connect()
+        table_data = config_db.get_table('KDUMP')
+        if table_data is not None:
+            config_data = table_data.get('config')
+            if config_data is not None:
+                if config_data.get('enabled').lower() == 'true':
+                    kdump_is_enabled = True
+    if kdump_is_enabled:
+        click.echo("kdump is enabled")
+    else:
+        click.echo("kdump is disabled")
+
+
+@kdump.command('status')
+def status():
+    """Show kdump status"""
+    clicommon.run_command("sonic-kdump-config --status")
+    clicommon.run_command("sonic-kdump-config --memory")
+    clicommon.run_command("sonic-kdump-config --num_dumps")
+    clicommon.run_command("sonic-kdump-config --files")
+
+
+@kdump.command('memory')
+def memory():
+    """Show kdump memory information"""
+    kdump_memory = "0M-2G:256M,2G-4G:320M,4G-8G:384M,8G-:448M"
+    config_db = ConfigDBConnector()
+    if config_db is not None:
+        config_db.connect()
+        table_data = config_db.get_table('KDUMP')
+        if table_data is not None:
+            config_data = table_data.get('config')
+            if config_data is not None:
+                kdump_memory_from_db = config_data.get('memory')
+                if kdump_memory_from_db is not None:
+                    kdump_memory = kdump_memory_from_db
+    click.echo("Memory Reserved: {}".format(kdump_memory))
+
+
+@kdump.command('num_dumps')
+def num_dumps():
+    """Show kdump max number of dump files"""
+    kdump_num_dumps = "3"
+    config_db = ConfigDBConnector()
+    if config_db is not None:
+        config_db.connect()
+        table_data = config_db.get_table('KDUMP')
+        if table_data is not None:
+            config_data = table_data.get('config')
+            if config_data is not None:
+                kdump_num_dumps_from_db = config_data.get('num_dumps')
+                if kdump_num_dumps_from_db is not None:
+                    kdump_num_dumps = kdump_num_dumps_from_db
+    click.echo("Maximum number of Kernel Core files Stored: {}".format(kdump_num_dumps))
+
+
+@kdump.command('files')
+def files():
+    """Show kdump kernel core dump files"""
+    clicommon.run_command("sonic-kdump-config --files")
+
+
+@kdump.command()
+@click.argument('record', required=True)
+@click.argument('lines', metavar='<lines>', required=False)
+def log(record, lines):
+    """Show kdump kernel core dump file kernel log"""
+    cmd = "sonic-kdump-config --file {}".format(record)
+
+    if lines is not None:
+        cmd += " --lines {}".format(lines)
+
+    clicommon.run_command(cmd)