The Tabular Parser¶
parsergen is a generic parser for show commands. The goal is to make
it simple to create a parser for any given show command one time, and then
reuse this parser to create tests for any values found within the output.
The main functions of parsergen are:
Find and verify expected values in show command output.
Provide an OS agnostic common interface to OS specific show commands.
Create once (per command), use many times (throughout all of your pyATS test suites).
Maintain a per command cache for fast processing.
Only parse the parts of the output that the user is interested in, thus avoiding wasting precious real-time.
Column Based Results¶
For column based table results one should use the
oper_fill_tabular class. To illustrate it’s use we’ll examine some standard
table results.
Full show arp example¶
RP/0/0/CPU0:one#show arp
Fri Jan 22 15:39:49.731 EST
-------------------------------------------------------------------------------
0/0/CPU0
-------------------------------------------------------------------------------
Address Age Hardware Addr State Type Interface
11.11.11.1 - 0292.77d4.d5ee Interface ARPA GigabitEthernet0/0/0/0
10.10.10.1 - 02b7.a23a.e076 Interface ARPA GigabitEthernet0/0/0/1
11.11.11.2 00:00:35 02e9.4522.5326 Dynamic ARPA GigabitEthernet0/0/0/0
10.10.10.2 00:00:35 02db.ebba.ecc4 Dynamic ARPA GigabitEthernet0/0/0/1
RP/0/0/CPU0:one#
We need to identify a few things in order to parse this output. First if there
are multiple tables we must identify what the title of each table is. In this
case the title is a card reference. Next we must identify the headers that
define the columns. For show arp the headers are Address, Age,
Hardware Addr, State, Type, and Interface. Finally we need to
determine how to uniquely identify entries from the table. These are the
index fields. For show arp these would be the Address and
Interface fields or columns 0 and 5. For this command that is all we need.
def test_log_arp_results_1 (self):
res = parsergen.oper_fill_tabular(device=device1,
show_command="show arp",
header_fields=
[ "Address",
"Age",
"Hardware Addr",
"State",
"Type",
"Interface" ],
index = [ 0, 5 ],
table_title_pattern = r"^(\d+/\d+/CPU\d+)")
log.info("Tabular parse result:\n" + pprint.pformat(res.entries))
Now when we execute the test the following output is logged:
Results:
{'0/0/CPU0': {'10.10.10.1': {'GigabitEthernet0/0/0/1': {'Address': '10.10.10.1',
'Age': '-',
'Hardware Addr': '02b7.a23a.e076',
'Interface': 'GigabitEthernet0/0/0/1',
'State': 'Interface',
'Type': 'ARPA'}},
'10.10.10.2': {'GigabitEthernet0/0/0/1': {'Address': '10.10.10.2',
'Age': '00:00:14',
'Hardware Addr': '02db.ebba.ecc4',
'Interface': 'GigabitEthernet0/0/0/1',
'State': 'Dynamic',
'Type': 'ARPA'}},
'11.11.11.1': {'GigabitEthernet0/0/0/0': {'Address': '11.11.11.1',
'Age': '-',
'Hardware Addr': '0292.77d4.d5ee',
'Interface': 'GigabitEthernet0/0/0/0',
'State': 'Interface',
'Type': 'ARPA'}},
'11.11.11.2': {'GigabitEthernet0/0/0/0': {'Address': '11.11.11.2',
'Age': '00:00:14',
'Hardware Addr': '02e9.4522.5326',
'Interface': 'GigabitEthernet0/0/0/0',
'State': 'Dynamic',
'Type': 'ARPA'}}}}
For multi-table results the n-level dictionary in self.entries is first indexed by the match groups from the table_title_pattern, in this case that is the card location. The rest of the indices are given by the values from the columns identified in the index arg. Once all these indices are specified the result is the actual entry dictionary. This dictionary is indexed by the header name of the value you want.
So for example if we want to see the ARP entry’s MAC address for the IP
10.10.10.2 on one’s GigabitEthernet0/0/0/1 interface we would take the
above results and use the following code:
addr = '10.10.10.2'
intf = 'GigabitEthernet0/0/0/1'
card = '0/0/CPU0'
macaddr = res.entries[card][addr][intf]['Hardware Addr']
log.info( addr + " on 0/0/CPU0 " + intf + " has MAC " + macaddr)
The following output is produced:
10.10.10.2 on GigabitEthernet0/0/0/1 has MAC 02db.ebba.ecc4
A Simpler show arp Example¶
It’s worth recognizing that in most cases the IP address alone is enough to uniquely identify an entry. Let’s use that knowledge and additionally specify a card location in our show command, as that will greatly simply the returned results.
RP/0/0/CPU0:one#show arp location 0/0/CPU0
Thu May 13 11:59:18.909 EDT
Address Age Hardware Addr State Type Interface
10.10.10.1 - 02b7.a23a.e076 Interface ARPA GigabitEthernet0/0/0/1
11.11.11.1 - 0292.77d4.d5ee Interface ARPA GigabitEthernet0/0/0/0
10.10.10.2 00:00:31 02db.ebba.ecc4 Dynamic ARPA GigabitEthernet0/0/0/1
11.11.11.2 00:00:31 02e9.4522.5326 Dynamic ARPA GigabitEthernet0/0/0/0
RP/0/0/CPU0:one#
Now for the test code.:
def test_log_arp_results_2 (self):
res = parsergen.oper_fill_tabular(device=device1,
show_command="show arp location 0/0/CPU0",
header_fields =
[ "Address",
"Age",
"Hardware Addr",
"State",
"Type",
"Interface" ])
log.info("Results:\n" + pprint.pformat(res.entries))
Notice we eliminate the index arg (by default column zero is considered the index column), as well as the table_title_pattern argument. Below we show the logged output from the above code.
Results:
{'12.12.12.1': {'Address': '12.12.12.1',
'Age': '-',
'Hardware Addr': '0292.77d4.d5ee',
'Interface': 'GigabitEthernet0/0/0/0',
'State': 'Interface',
'Type': 'ARPA'},
'12.12.12.2': {'Address': '12.12.12.2',
'Age': '00:47:27',
'Hardware Addr': '02e9.4522.5326',
'Interface': 'GigabitEthernet0/0/0/0',
'State': 'Dynamic',
'Type': 'ARPA'},
'13.13.13.1': {'Address': '13.13.13.1',
'Age': '-',
'Hardware Addr': '02b7.a23a.e076',
'Interface': 'GigabitEthernet0/0/0/1',
'State': 'Interface',
'Type': 'ARPA'},
'13.13.13.2': {'Address': '13.13.13.2',
'Age': '00:47:27',
'Hardware Addr': '02db.ebba.ecc4',
'Interface': 'GigabitEthernet0/0/0/1',
'State': 'Dynamic',
'Type': 'ARPA'}}
TEST 2010-01-22 16:26:41,113: PASS: example_suite_t.test_log_arp_results_2
As you can see now we simply have to index using the IP to get at the actual
entry dictionary. So to view the MAC address and interface for IP 10.10.10.2
we use the following code.
addr = '10.10.10.2'
macaddr = res.entries[addr]['Hardware Addr']
intf = res.entries[addr]['Interface']
exec_logger.info(twoaddr + " on " + intf + " has MAC addr " + macaddr)
Resulting in the following output:
10.10.10.2 on GigabitEthernet0/0/0/1 has MAC addr 02db.ebba.ecc4
Tabular parsing support for delimited Multi-line header tables¶
Paresergen supports parisng delimited tables with multi-line headers as illustrated in the below example.
sysadmin-vm:0_RP0# show controller sfe driver rack 0
Sun Apr 23 21:24:51.773 UTC-07:00
=========================================================================
SFE Driver information
=========================================================================
Driver Version: 1 (1.1)
Functional role: Active, ISSU role: NA
Rack: 0/RP0, Type: lcc, Number: 0, IP Address: 192.1.0.1
Startup time : 2017 Apr 15 04:04:32.117
Availability Masks :
Card: 0x1 Asic: 0xF Exp Asic: 0xF
Unicast/Multicast (ratio) : 0
+----------------------------------------------------------------+
|Process | Connection | Registration| Connection | DLL |
|/Lib | status | status | requests | registration |
+----------------------------------------------------------------+
| PM | Active | n/a | 1| n/a |
| PL-LOCAL| Active | Active | 1| n/a |
| FSDB | Active | Active | 1| n/a |
| FGID | Active | Active | 1| n/a |
| CM | Active | Active | 1| n/a |
| CCC | Active | n/a | 1| n/a |
| GASPP | n/a | n/a | n/a| n/a |
| CIH | n/a | n/a | n/a| Yes |
+----------------------------------------------------------------+
Asics :
HP - HotPlug event, PON - Power ON reset, WB - Warm Boot, A - All
HR - Hard Reset, DC - Disconnect signal, DL - DownLoad
+-----------------------------------------------------------------------------------+
| Asic inst.|card|HP|Asic| Asic | Admin|plane| Fgid| Asic State |DC| Last |PON|HR |
| (R/S/A) |pwrd| |type| class | /Oper|/grp | DL | | | init |(#)|(#)|
+-----------------------------------------------------------------------------------+
| 0/FC0/0 | UP | 1| s13| FE1600| UP/UP| 0/0 | DONE| NRML | 0| PON | 1| 0|
| 0/FC0/1 | UP | 1| s13| FE1600| UP/UP| 0/1 | DONE| NRML | 0| PON | 1| 0|
| 0/FC0/2 | UP | 1| s13| FE1600| UP/UP| 0/2 | DONE| NRML | 0| PON | 1| 0|
| 0/FC0/3 | UP | 1| s13| FE1600| UP/UP| 0/3 | DONE| NRML | 0| PON | 1| 0|
+-----------------------------------------------------------------------------------+
We will parse the second table. We only need to pass the delimiter so parsergen will be able to identify the table columns borders.
Now for the test code.:
def test_tabular_parser_12(self):
result = oper_fill_tabular(device=device1,
show_command="show controller sfe driver rack 0",
refresh_cache=True,
header_fields=
[['Asic inst\.',
'card',
'HP',
'Asic',
'Asic',
'Admin',
'plane',
'Fgid',
'Asic State',
'DC',
'Last',
'PON',
'HR'],
['\(R/S/A\)',
'pwrd',
'',
'type',
'class',
'/Oper',
'/grp',
'DL',
'',
'',
'init',
'\(#\)',
'\(#\)']],
label_fields=
[ "Asic inst. (R/S/A) ",
"card pwrd",
"HP",
"Asic type",
"Asic class",
"Admin /Oper",
"plane /grp",
"Fgid DL",
"Asic State",
"DC",
"Last init",
"PON State (#)",
"HR (#)" ],
index = [ 0, 12 ],
delimiter = '|')
log.info("Results:\n" + pprint.pformat(res.entries))
Below we show the parsed output from the above code.
Results:
{'0/FC0/0': {'Admin /Oper': 'UP/UP',
'Asic State': 'NRML',
'Asic class': 'FE1600',
'Asic inst. (R/S/A) ': '0/FC0/0',
'Asic type': 's13',
'DC': '0',
'Fgid DL': 'DONE',
'HP': '1',
'HR (#)': '0',
'Last init': 'PON',
'PON State (#)': '1',
'card pwrd': 'UP',
'plane /grp': '0/0'},
'0/FC0/1': {'Admin /Oper': 'UP/UP',
'Asic State': 'NRML',
'Asic class': 'FE1600',
'Asic inst. (R/S/A) ': '0/FC0/1',
'Asic type': 's13',
'DC': '0',
'Fgid DL': 'DONE',
'HP': '1',
'HR (#)': '0',
'Last init': 'PON',
'PON State (#)': '1',
'card pwrd': 'UP',
'plane /grp': '0/1'},
'0/FC0/2': {'Admin /Oper': 'UP/UP',
'Asic State': 'NRML',
'Asic class': 'FE1600',
'Asic inst. (R/S/A) ': '0/FC0/2',
'Asic type': 's13',
'DC': '0',
'Fgid DL': 'DONE',
'HP': '1',
'HR (#)': '0',
'Last init': 'PON',
'PON State (#)': '1',
'card pwrd': 'UP',
'plane /grp': '0/2'},
'0/FC0/3': {'Admin /Oper': 'UP/UP',
'Asic State': 'NRML',
'Asic class': 'FE1600',
'Asic inst. (R/S/A) ': '0/FC0/3',
'Asic type': 's13',
'DC': '0',
'Fgid DL': 'DONE',
'HP': '1',
'HR (#)': '0',
'Last init': 'PON',
'PON State (#)': '1',
'card pwrd': 'UP',
'plane /grp': '0/3'}}
Parse using device output¶
Parsergen now supports working without passing the device as an argument,
user can pass the device output (as a string) along with the OS (for
abstraction purpose) instead.
def test_non_tabular_parser(self):
"""
Test non tabular parser when passing a device output
and device os only and compare against selected tags.
"""
pure_cli = dedent(self.showCommandOutput1)
attrValPairsToCheck = [
('show.intf.if_name', 'MgmtEth0/0/CPU0/0'),
('show.intf.line_protocol', 'up'),
('show.intf.ip_address', '10.30.108.132'),
('show.intf.mtu', 1514),
('show.intf.admin_state', 'up'),
]
device_os = 'iosxr'
pgcheck = oper_check (
attrvalpairs = attrValPairsToCheck,
show_command = \
('show_interface_<WORD>', [], {'ifname':'MgmtEth0/0/CPU0/0'}),
refresh_cache=True,
device_output = pure_cli,
device_os = device_os)
result = pgcheck.parse()
self.assertTrue(result)
self.assertEqual(parsergen.ext_dictio['device_name'], self.outputDict2)
def test_tabular_parser(self):
"""
Test tabular parser when passing a device output
and device os only.
"""
pure_cli='''
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0 10.1.10.20 YES NVRAM up up
GigabitEthernet1/0/1 unassigned YES unset up up
GigabitEthernet1/0/10 unassigned YES unset down down
'''
device_os = 'iosxe'
res = parsergen.oper_fill_tabular(header_fields=
[ "Interface",
"IP-Address",
"OK\?",
"Method",
"Status",
"Protocol" ],
label_fields=
[ "Interface",
"IP-Address",
"OK?",
"Method",
"Status",
"Protocol" ],
index=[ 0, 5 ],
device_output = pure_cli,
device_os = device_os)
self.assertEqual(res.entries, outputDict4)
outputDict4 = {
'GigabitEthernet0/0':
{'up':
{'IP-Address': '10.1.10.20',
'Interface': 'GigabitEthernet0/0',
'Method': 'NVRAM',
'OK?': 'YES',
'Protocol': 'up',
'Status': 'up'}},
'GigabitEthernet1/0/1':
{'up':
{'IP-Address': 'unassigned',
'Interface': 'GigabitEthernet1/0/1',
'Method': 'unset',
'OK?': 'YES',
'Protocol': 'up',
'Status': 'up'}},
'GigabitEthernet1/0/10':
{'down':
{'IP-Address': 'unassigned',
'Interface': 'GigabitEthernet1/0/10',
'Method': 'unset',
'OK?': 'YES',
'Protocol': 'down',
'Status': 'down'}}}
Note
Here is the list of the supported OSes: [ ‘ios’, ‘iosxr’, ‘iosxe’, ‘nxos’, ‘calvados’, ‘iox’,
‘pix’, ‘asa’, ‘sanos’, ‘dcos’, ‘aireos’, ‘linux’ ]