add proc-net-dev parser

tests/fixtures/linux-proc/net_dev.json

@@ -0,0 +1 @@
+[{"interface":"lo","r_bytes":13222,"r_packets":152,"r_errs":0,"r_drop":0,"r_fifo":0,"r_frame":0,"r_compressed":0,"r_multicast":0,"t_bytes":13222,"t_packets":152,"t_errs":0,"t_drop":0,"t_fifo":0,"t_colls":0,"t_carrier":0,"t_compressed":0},{"interface":"ens33","r_bytes":60600053,"r_packets":109378,"r_errs":0,"r_drop":0,"r_fifo":0,"r_frame":0,"r_compressed":0,"r_multicast":0,"t_bytes":44256546,"t_packets":121425,"t_errs":0,"t_drop":0,"t_fifo":0,"t_colls":0,"t_carrier":0,"t_compressed":0}]

tests/test_proc_net_dev.py

@@ -0,0 +1,44 @@
+import os
+import unittest
+import json
+from typing import Dict
+import jc.parsers.proc_net_dev
+
+THIS_DIR = os.path.dirname(os.path.abspath(__file__))
+
+
+class MyTests(unittest.TestCase):
+    f_in: Dict = {}
+    f_json: Dict = {}
+
+    @classmethod
+    def setUpClass(cls):
+        fixtures = {
+            'proc_net_dev': (
+                'fixtures/linux-proc/net_dev',
+                'fixtures/linux-proc/net_dev.json')
+        }
+
+        for file, filepaths in fixtures.items():
+            with open(os.path.join(THIS_DIR, filepaths[0]), 'r', encoding='utf-8') as a, \
+                 open(os.path.join(THIS_DIR, filepaths[1]), 'r', encoding='utf-8') as b:
+                cls.f_in[file] = a.read()
+                cls.f_json[file] = json.loads(b.read())
+
+
+    def test_proc_net_dev_nodata(self):
+        """
+        Test 'proc_net_dev' with no data
+        """
+        self.assertEqual(jc.parsers.proc_net_dev.parse('', quiet=True), [])
+
+    def test_proc_net_dev(self):
+        """
+        Test '/proc/net/dev'
+        """
+        self.assertEqual(jc.parsers.proc_net_dev.parse(self.f_in['proc_net_dev'], quiet=True),
+                                                       self.f_json['proc_net_dev'])
+
+
+if __name__ == '__main__':
+    unittest.main()