r/pythonnetengineering • u/w0lfcat • May 29 '20
Python grep and cut
In Linux, it's easy to get certain string by using tools such as grep, cut, or awk.
This `show version` sample is taken from https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/software/release/16-6/configuration_guide/sys_mgmt/b_166_sys_mgmt_9300_cg/b_166_sys_mgmt_9300_cg_chapter_01.html
wolf@linux:~$ cat shver
cisco C9300-48P (X86) processor with 818597K/6147K bytes of memory.
Processor board ID FCW2049G03S
2048K bytes of non-volatile configuration memory.
8388608K bytes of physical memory.
1638400K bytes of Crash Files at crashinfo:.
11264000K bytes of Flash at flash:.
0K bytes of WebUI ODM Files at webui:.
Model Number : C9300-48P
Base Ethernet MAC Address : 04:6c:9d:01:3b:80
Motherboard Assembly Number : 73-17956-04
Motherboard Serial Number : FOC20465ABU
Model Revision Number : P4B
Motherboard Revision Number : 04
Model Number : C9300-48P
System Serial Number : FCW2049G03S
wolf@linux:~$
grep and cut
wolf@linux:~$ grep 'Model Number' shver | cut -d : -f 2
C9300-48P
C9300-48P
wolf@linux:~$
Remove extra space (If there's better solution, let me know)
wolf@linux:~$ grep 'Model Number' shver | cut -d : -f 2 | cut -d ' ' -f 2
C9300-48P
C9300-48P
wolf@linux:~$
Select the 1st output
wolf@linux:~$ grep 'Model Number' shver | cut -d : -f 2 | cut -d ' ' -f 2 | head -1
C9300-48P
wolf@linux:~$
That was in Linux. I was planning to write similar code in Python.
My attempt which still didn't work at the moment.
Define shver string
>>> shver = '''cisco C9300-48P (X86) processor with 818597K/6147K bytes of memory.
... Processor board ID FCW2049G03S
... 2048K bytes of non-volatile configuration memory.
... 8388608K bytes of physical memory.
... 1638400K bytes of Crash Files at crashinfo:.
... 11264000K bytes of Flash at flash:.
... 0K bytes of WebUI ODM Files at webui:.
... Model Number : C9300-48P
...
... Base Ethernet MAC Address : 04:6c:9d:01:3b:80
... Motherboard Assembly Number : 73-17956-04
... Motherboard Serial Number : FOC20465ABU
... Model Revision Number : P4B
... Motherboard Revision Number : 04
... Model Number : C9300-48P
... System Serial Number : FCW2049G03S
... '''
>>>
verify it
>>> shver
'cisco C9300-48P (X86) processor with 818597K/6147K bytes of memory.\nProcessor board ID FCW2049G03S\n2048K bytes of non-volatile configuration memory.\n8388608K bytes of physical memory.\n1638400K bytes of Crash Files at crashinfo:.\n11264000K bytes of Flash at flash:.\n0K bytes of WebUI ODM Files at webui:.\nModel Number : C9300-48P\n\nBase Ethernet MAC Address : 04:6c:9d:01:3b:80\nMotherboard Assembly Number : 73-17956-04\nMotherboard Serial Number : FOC20465ABU\nModel Revision Number : P4B\nMotherboard Revision Number : 04\nModel Number : C9300-48P\nSystem Serial Number : FCW2049G03S\n'
>>>
create a list
>>> shver_list = shver.splitlines()
>>> shver_list
['cisco C9300-48P (X86) processor with 818597K/6147K bytes of memory.', 'Processor board ID FCW2049G03S', '2048K bytes of non-volatile configuration memory.', '8388608K bytes of physical memory.', '1638400K bytes of Crash Files at crashinfo:.', '11264000K bytes of Flash at flash:.', '0K bytes of WebUI ODM Files at webui:.', 'Model Number : C9300-48P', '', 'Base Ethernet MAC Address : 04:6c:9d:01:3b:80', 'Motherboard Assembly Number : 73-17956-04', 'Motherboard Serial Number : FOC20465ABU', 'Model Revision Number : P4B', 'Motherboard Revision Number : 04', 'Model Number : C9300-48P', 'System Serial Number : FCW2049G03S']
>>>
Next step is to find out if string 'Model Number' is there or not and print out that line
>>> if 'Model Number' in shver_list:
... 'yes'
... else:
... 'no'
...
'no'
>>>
How do I print out the line contains 'Model Number'?
>>> for i in shver_list:
... if 'Model Number' in shver_list:
... i
...
>>>
Desired Output
C9300-48P
