[sflow_test.py]: Fix show sflow display. (sonic-net#1054)

Changes:
-- Display ipv4 address with left adjust of 25 width and with space before UDP.
-- IPv6 address will be displayed as is.
-- Add test data to appl_db.json and config_db.json
-- add test file sflow_test.py
-- use pass_db decorator for sflow_interface.
-- since sflow needs ctx, create use Db() in function.

Signed-off-by: Praveen Chaudhary pchaudhary@linkedin.com

show/main.py

@@ -1714,20 +1714,18 @@ def policer(policer_name, verbose):
 @click.pass_context
 def sflow(ctx):
     """Show sFlow related information"""
-    config_db = ConfigDBConnector()
-    config_db.connect()
-    ctx.obj = {'db': config_db}
     if ctx.invoked_subcommand is None:
-        show_sflow_global(config_db)
+        db = Db()
+        show_sflow_global(db.cfgdb)
 
 #
 # 'sflow command ("show sflow interface ...")
 #
 @sflow.command('interface')
-@click.pass_context
-def sflow_interface(ctx):
+@clicommon.pass_db
+def sflow_interface(db):
     """Show sFlow interface information"""
-    show_sflow_interface(ctx.obj['db'])
+    show_sflow_interface(db.cfgdb)
 
 def sflow_appDB_connect():
     db = SonicV2Connector(host='127.0.0.1')
@@ -1789,7 +1787,7 @@ def show_sflow_global(config_db):
     click.echo("\n  {} Collectors configured:".format(len(sflow_info)))
     for collector_name in sorted(sflow_info.keys()):
         click.echo("    Name: {}".format(collector_name).ljust(30) +
-                   "IP addr: {}".format(sflow_info[collector_name]['collector_ip']).ljust(20) +
+                   "IP addr: {} ".format(sflow_info[collector_name]['collector_ip']).ljust(25) +
                    "UDP port: {}".format(sflow_info[collector_name]['collector_port']))
 
 

tests/mock_tables/appl_db.json

@@ -1,4 +1,20 @@
 {
+    "SFLOW_SESSION_TABLE:Ethernet0": {
+        "admin_state": "up",
+        "sample_rate": "2500"
+    },
+    "SFLOW_SESSION_TABLE:Ethernet4": {
+        "admin_state": "up",
+        "sample_rate": "1000"
+    },
+    "SFLOW_SESSION_TABLE:Ethernet112": {
+        "admin_state": "up",
+        "sample_rate": "1000"
+    },
+    "SFLOW_SESSION_TABLE:Ethernet116": {
+        "admin_state": "up",
+        "sample_rate": "5000"
+    },
     "PORT_TABLE:Ethernet0": {
         "index": "0",
         "lanes": "0",

tests/mock_tables/config_db.json

@@ -1,4 +1,17 @@
 {
+    "SFLOW|global": {
+        "admin_state": "up",
+        "agent_id": "eth0",
+        "polling_interval": "0"
+    },
+    "SFLOW_COLLECTOR|prod": {
+            "collector_ip": "fe80::6e82:6aff:fe1e:cd8e",
+            "collector_port": "6343"
+    },
+    "SFLOW_COLLECTOR|ser5": {
+            "collector_ip": "172.21.35.15",
+            "collector_port": "6343"
+    },
     "BREAKOUT_CFG|Ethernet0": {
         "brkout_mode": "4x25G[10G]"
     },

tests/sflow_test.py

@@ -0,0 +1,64 @@
+import os
+import sys
+import pytest
+from click.testing import CliRunner
+from utilities_common.db import Db
+
+import show.main as show
+import mock_tables.dbconnector
+
+# Expected output for 'show sflow'
+show_sflow_output = ''+ \
+"""
+sFlow Global Information:
+  sFlow Admin State:          up
+  sFlow Polling Interval:     0
+  sFlow AgentID:              eth0
+
+  2 Collectors configured:
+    Name: prod                IP addr: fe80::6e82:6aff:fe1e:cd8e UDP port: 6343
+    Name: ser5                IP addr: 172.21.35.15    UDP port: 6343
+"""
+
+# Expected output for 'show sflow interface'
+show_sflow_intf_output = ''+ \
+"""
+sFlow interface configurations
++-------------+---------------+-----------------+
+| Interface   | Admin State   |   Sampling Rate |
++=============+===============+=================+
+| Ethernet0   | up            |            2500 |
++-------------+---------------+-----------------+
+| Ethernet4   | up            |            1000 |
++-------------+---------------+-----------------+
+| Ethernet112 | up            |            1000 |
++-------------+---------------+-----------------+
+| Ethernet116 | up            |            5000 |
++-------------+---------------+-----------------+
+"""
+
+class TestShowSflow(object):
+    @classmethod
+    def setup_class(cls):
+        print("SETUP")
+        os.environ["UTILITIES_UNIT_TESTING"] = "1"
+
+    def test_show_sflow(self):
+        runner = CliRunner()
+        result = runner.invoke(show.cli.commands["sflow"], [], obj=Db())
+        print(sys.stderr, result.output)
+        assert result.exit_code == 0
+        assert result.output == show_sflow_output
+
+    def test_show_sflow_intf(self):
+        runner = CliRunner()
+        result = runner.invoke(show.cli.commands["sflow"].commands["interface"], [], obj=Db())
+        print(sys.stderr, result.output)
+        assert result.exit_code == 0
+        assert result.output == show_sflow_intf_output
+
+    @classmethod
+    def teardown_class(cls):
+        print("TEARDOWN")
+        os.environ["PATH"] = os.pathsep.join(os.environ["PATH"].split(os.pathsep)[:-1])
+        os.environ["UTILITIES_UNIT_TESTING"] = "0"