Expect Script: Parse Specific Info From Cisco CLI - parsing

Question

I'm new to Expect scripting, and trying to parse Cisco router ACL output.
I'm specifically trying to parse IP addresses between the first 2 remark lines. Any help greatly appreciated.
Here's one of my random attempts. It parses IP addresses from the ACL, but doesn't stop at the 2nd remark line:
send "show run | section ip access-list extended OUTSIDE\r\n"
set ip {}
expect {
"remark ##### DENIED HOSTS #####\r\n" {
expect -re {(\d+\.\d+\.\d+\.\d+)} {
set ip "${ip}$expect_out(0,string)"
puts $ip
set ip {}
exp_continue
}
}
}
Not only does the script not stop at the 2nd remark line like I want it to, but it doesn't seem to have an exit point and waits for Expect to timeout.
Random sample ACL for reference:
ip access-list extended OUTSIDE
remark ##### DENIED HOSTS #####
deny ip host 2.2.2.2 any
deny ip host 9.9.9.9 any
deny ip host 8.7.6.5 any
deny ip host 5.6.7.8 any
deny ip host 5.5.5.5 any
deny ip host 4.4.4.4 any
deny ip host 3.3.3.3 any
remark ########################
permit tcp any any eq 22
deny ip any any
permit ip host 2.3.5.1 any
I basically want to parse addresses from 2.2.2.2 to 3.3.3.3, but then exit once the script reaches the 2nd remark line.

Answer 1

With exp_continue, it is always better to add the case where we want to terminate from expect. So that, if the exit case arrived, we can terminate from the expect. Else, obviously timeout will happen.
E.g.
expect{
“p” {send “\r\r\r”; exp_continue}
“+” {incr foo; exp_continue}
“i” {puts "test"; exp_continue}
“quit” exit
}
As you can see, if the word 'quit' comes, then it will be exited.
Lets come to your question. You need to exit from expect when the word
'remark ########################' arrives. But, if we code like,
expect {
"remark ##### DENIED HOSTS #####\r\n" {
expect {
"remark ########################" {exit}
-re {(\d+\.\d+\.\d+\.\d+)} {
set ip "${ip}$expect_out(0,string)"
puts "-->$ip"
set ip {}
exp_continue
}
}
}
}
Program will terminate the expect while the ip parsing is in progress at the middle of anything.
Instead of doing this way, you can better get the whole output and try to parse it as a separate variable, to avoid overhead within expect.
send "show run | section ip access-list extended OUTSIDE\r\n"
expect {
-re {deny\s+ip\s+host\s+(.*)remark} { puts "match found" }
timeout {puts "timeout happened"}
}
Now we have the match and it will be available in the variable expect_out(1,string).
Then we can do regexp in the variable and parse the ip address.
puts [ regexp -inline -all {\d.\d.\d.\d} $expect_out(1,string) ]
You can try one more way as below. Instead of doing regular expression at the expect, you can simply get the whole output and then do the regexp as below.
send "sh run | section ip access-list extended OUTSIDE\r"
#Assuming your router's hostname is `Router`
expect "Router#"
#output will hold the command output.
set output expect_out(buffer)
puts $output
set ip_list [regexp -inline -all {\d.\d.\d.\d} $output]
foreach ip $ip_list {
puts $ip
}

Answer 2

Thanks to Dinesh!!!
Reposting the final working code (or a mix of Dinesh-provided code) here so it's not lost in all the text above (and so I can format more easily than in the comment section).
send "show run | section ip access-list extended OUTSIDE\n"
expect -re {remark(.*)remark}
set output $expect_out(buffer)
#puts $output
puts "\r"
set ip_list [regexp -inline -all {\d.\d.\d.\d} $output]
foreach ip $ip_list {
puts $ip
}
I commented out the 1st puts line, but left it there to use when testing to see what's actually being stored in $output.
Here's the ACL that was parsed from the router CLI:
ip access-list extended OUTSIDE
remark ##### DENIED HOSTS #####
deny ip host 2.2.2.2 any
deny ip host 9.9.9.9 any
deny ip host 8.7.6.5 any
deny ip host 5.6.7.8 any
deny ip host 5.5.5.5 any
deny ip host 4.4.4.4 any
deny ip host 3.3.3.3 any
remark ########################
permit tcp any any eq 22
deny ip host 82.28.82.28 any
permit ip host 2.3.5.1 any
I know, it's a completely convoluted ACL, but it worked great for testing.
Here's Expect script output after parsing the ACL:
2.2.2.2
9.9.9.9
8.7.6.5
5.6.7.8
5.5.5.5
4.4.4.4
3.3.3.3
Any / all IP addresses after the 2nd ACL remark line are ignored as desired!
Thanks Dinesh!

Answer 3

why dont you use perl with Net::Telnet::Cisco ?
https://metacpan.org/pod/Net::Telnet::Cisco