Merge pull request #1 from CiscoDevNet/string_implementation

Adding string implementation

Author: Siming Yuan

coding-102-parsers/strings.py

@@ -8,4 +8,146 @@
 
 '''
 
-import re
+import re
+import pprint
+
+
+STRING = '''
+ Neighbor: 21.0.0.1, Address-Family: ipv4 Unicast (VRF1)
+   Locally configured policies:
+    route-map RMAP in
+    route-map RMAP2 out
+ Neighbor: 21.0.0.2, Address-Family: ipv6 Unicast (VRF2)
+   Locally configured policies:
+    route-map RMAP3 in
+    route-map RMAP4 out
+ Neighbor: 21.0.0.3, Address-Family: VPNv4 Unicast
+   Locally configured policies:
+    route-map RMAP5 in
+    route-map RMAP6 out
+ Neighbor: 21.0.0.4, Address-Family: VPNv6 Unicast (VRF2)
+   Locally configured policies:
+    route-map RMAP7 in
+    route-map RMAP8 out
+    '''
+
+# initialize dictionary
+PYTHON_DICT = {}
+
+# split the output into seperate lines
+for line in STRING.splitlines():
+    # strip the line from any trailing white spaces
+    line = line.rstrip()
+
+    # regexp to parse the below different outputs
+    # ** Neighbor: 21.0.0.1, Address-Family: ipv4 Unicast
+    # ** Neighbor: 21.0.0.2, Address-Family: VPNv4 Unicast (VRF2)
+    p1 = re.compile(r'^\s*Neighbor: +(?P<neighbor_name>[0-9\.]+),'
+                     ' +Address-Family:'
+                     ' +(?P<address_family_name>[a-zA-Z0-9\s]+)'
+                     '( +\((?P<vrf_name>[a-zA-Z0-9]+)\))?$')
+    # check if the regexp matched with the line
+    m = p1.match(line)
+    if m:
+        # gather the prased keys
+        neighbor_name = m.groupdict()['neighbor_name']
+        address_family_name = m.groupdict()['address_family_name']
+        # check if vrf has been identified in the output, if not default
+        # it to 'default'
+        if m.groupdict()['vrf_name']:
+            vrf_name = m.groupdict()['vrf_name']
+        else:
+            vrf_name = 'default'
+        continue
+
+    # regexp to parse the below outputs
+    # ** route-map RMAP in
+    # ** route-map RMAP out
+    p2 = re.compile(r'\s*route-map +(?P<route_map_name>[a-zA-Z0-9]+) '
+					 '+(?P<direction>[a-z]+)')
+    # check if the regexp matched with the line
+    m = p2.match(line)
+    if m:
+        # gather the prased keys
+        route_map_name = m.groupdict()['route_map_name']
+        direction = m.groupdict()['direction']
+
+        # build the desired structure/hierarchy out of the parsed output
+        if 'vrf' not in PYTHON_DICT:
+            PYTHON_DICT['vrf'] = {}
+        if vrf_name not in PYTHON_DICT['vrf']:
+            PYTHON_DICT['vrf'][vrf_name] = {}
+        if 'neighbor' not in PYTHON_DICT['vrf'][vrf_name]:
+            PYTHON_DICT['vrf'][vrf_name]['neighbor'] = {}
+        if neighbor_name not in PYTHON_DICT['vrf'][vrf_name]['neighbor']:
+            PYTHON_DICT['vrf'][vrf_name]['neighbor'][neighbor_name] = {}
+        if 'address_family' not in PYTHON_DICT['vrf'][vrf_name]['neighbor']\
+			[neighbor_name]:
+            PYTHON_DICT['vrf'][vrf_name]['neighbor'][neighbor_name]\
+				['address_family'] = {}
+        if address_family_name not in PYTHON_DICT['vrf'][vrf_name]['neighbor']\
+			[neighbor_name]['address_family']:
+            PYTHON_DICT['vrf'][vrf_name]['neighbor'][neighbor_name]\
+				['address_family'][address_family_name] = {}
+
+        if direction == 'in':
+            PYTHON_DICT['vrf'][vrf_name]['neighbor'][neighbor_name]\
+				['address_family'][address_family_name]['route_map_in'] = \
+					route_map_name
+        else:
+            PYTHON_DICT['vrf'][vrf_name]['neighbor'][neighbor_name]\
+				['address_family'][address_family_name]['route_map_out'] = \
+					route_map_name
+
+        continue
+
+# print the parsed built structure
+pprint.pprint(PYTHON_DICT)
+
+# Expected output
+# ===============
+
+# PYTHON_DICT = {
+#     'vrf':
+#         {'VRF1':
+#             {'neighbor':
+#                 {'21.0.0.1':
+#                     {'address_family':
+#                         {'VPNv4 Unicast':
+#                             {'route_map_in': 'RMAP',
+#                              'route_map_out': 'RMAP2'}
+#                         }
+#                     }
+#                 }
+#             },
+#         'VRF2':
+#             {'neighbor':
+#                 {'21.0.0.2':
+#                     {'address_family':
+#                         {'VPNv6 Unicast':
+#                             {'route_map_in': 'RMAP3',
+#                              'route_map_out': 'RMAP4'}
+#                         }
+#                     },
+#                 '21.0.0.4':
+#                     {'address_family':
+#                         {'VPNv6 Unicast':
+#                             {'route_map_in': 'RMAP7',
+#                              'route_map_out': 'RMAP8'}
+#                         }
+#                     }
+#                 }
+#             },
+#         'default':
+#             {'neighbor':
+#                 {'21.0.0.3':
+#                     {'address_family':
+#                         {'VPNv4 Unicast':
+#                             {'route_map_in': 'RMAP5',
+#                              'route_map_out': 'RMAP6'}
+#                         }
+#                     }
+#                 }
+#             }
+#         }
+#     }