[SOLVED] Query about trimming and converting date from txt file

JugaruGabi · 08-24-2020, 05:50 AM

Hello,

So I am facing the following situation.
A txt file contains the following information:

Code:

Owner: CN=servername28, O=YourSociety, DC=host, DC=com
Valid from: Fri Jul 10 21:52:55 CEST 2020 until: Sat Jan 16 18:00:00 CET 2021
Owner: CN=servernameA29, O=YourSociety, DC=host, DC=com
Valid from: Fri Jul 10 21:52:49 CEST 2020 until: Sat Jan 16 18:00:00 CET 2021
Owner: CN=servernameB30, O=YourSociety, DC=host, DC=com
Valid from: Fri Jul 10 21:52:58 CEST 2020 until: Sat Jan 16 18:00:00 CET 2021
Owner: CN=servernameA31, O=YourSociety, DC=host, DC=com
Valid from: Fri Jul 10 21:43:34 CEST 2020 until: Sat Jan 16 18:00:00 CET 2021
Owner: CN=servernameB32, O=YourSociety, DC=host, DC=com
Valid from: Fri Jul 10 21:46:36 CEST 2020 until: Sat Jan 16 18:00:00 CET 2021

Now, I need to perform the following actions:
1. For each occurrence I just need to keep only "CN=servernameA/BXX, "
2. Remove the Valid from: <full date> until
3. Convert date from until from Sat Jan 16 18:00:00 CET 2021 to 16-01-2021
4. Move the resulted converted date after the "CN=servernameA/BXX, " on line above.

Am using a monitoring tool that reads the information from the txt file which is formatted this way and sends out notifications based on the expiration dates.

How could I achieve these things?

syg00 · 08-24-2020, 06:10 AM

Read a record, remove unwanted data, save good data - read next record, do likewise; print final record after converting date. Pick a language you are comfortable with.
This is your problem not ours, make an effort. We'll help where we can if you run into roadblocks.

JugaruGabi · 08-24-2020, 08:52 AM

Hey,

I would love to get this sorted out using bash but I don't know how to achieve what I need. While for the rest I digged and sorted out in the meantime, the biggest problem is that I have no idea how to convert the date "until: Sat Jan 16 18:00:00 CET 2021" to 16-Jan-2021 in all that big file automatically.

This is because I have no idea how to define the "until: long date" as parameters to all my 72 servers automatically and not have to manually edit and define each server's expiration date similar to:

Code:

a='Sat Jan 16 18:00:00 CET 2021'

so I can run:

Code:

b=`date --date="$a" '+%d-%b-%Y'`
echo $b

Long story short, I am using the keytool command to pull the records regarding the expiration date of the certs from my servers into one big txt file.
This file is processed and trimmed to get the desired result.
But I have no idea how to define the "until date" as parameter for each line and to have the command mentioned above for the desired date format.

scasey · 08-24-2020, 08:57 AM

Doesn’t the code in #3 do what you want? Looks like it should.

JugaruGabi · 08-24-2020, 09:01 AM

The single command works.
But how do I pass that date automatically as parameter $a in the big text file for each server?
So I am able to issue the "echo $b" command using a script and have the desired date format in the final form of the txt file?

scasey · 08-24-2020, 09:06 AM

Parse the date from the input into $a, do the conversion to $b, use $b in the output for each line.
You have already managed getting the CN part, right? Looks like you need to read two lines in for each one line out...

Turbocapitalist · 08-24-2020, 09:28 AM

AWK can do most of it, with one call to date from inside the script.

individual · 08-24-2020, 10:15 AM

If you want to use plain Bash, you can read the file into an array and manipulate the lines how you need.

Code:

#!/usr/bin/env bash

readarray lines <certsfile
count=${#lines[@]}

i=1
while [[ $i -lt $count ]]; do
    # extract the certificate name
    server="${lines[$((i-1))]}"
    server="${server%%,*}"
    server="${server##* }"

    # convert the date/time to date
    datetime="$(date +'%d-%m-%Y' <<<"${lines[$i]}")"

    echo "$server $datetime"
    i=$((i + 2))
done

scasey · 08-24-2020, 10:43 AM

I'd probably do it in perl...but I'd have wanted to see some effort from the OP first.

astrogeek · 08-24-2020, 01:30 PM

I second awk as probably the easiest and most flexible tool for exactly this kind of text manipulation, especially with multi-line records. Consider using ^Owner as the record separator, then the number of fields appears consistent and the problem immediately becomes a matter of selecting and transforming indexed fields into the output stream.

That said, bash can do it easily enough if you prefer to do it that way, suggest using array structures as others have said. The key as always is to organize the transformation tasks into well defined individual parts, testing them in isolation, then build the final result from those pieces.

The call to date can perform the date translation from either bash or awk, but you can do that with a simple array based operation, too, if desired.

As others have indicated, most members are more willing to help you solve problems with your own efforts than to simply produce a working solution to order. Give each part of the puzzle your best effort and show what you have tried and cannot get working. That helps you understand each problem more clearly and also helps those offering help to offer more specific suggestions consistent with your own chosen approach.

Good luck!

scasey · 08-25-2020, 04:16 AM

awk is not something I’ve yet learned...I probably should. I’m currently trying to get up to speed with CSS...amazing...

syg00 · 08-25-2020, 05:45 AM

Something simple to p'raps help kick things off - date needs managing ... Relies on very specific records, which is generally to be avoided, but done for simplicity.

Code:

 awk '/^Owner/ {printf "%s ",$2 ; next} ; {a=$10" "$11" "$12" "$13" "$14" "$15 ; print a}' server.log

JugaruGabi · 08-31-2020, 01:12 AM

I have managed to get it sorted out next day since the posting.
However, had something to do.

Solution is similar to what @syg00 suggested:

Code:

string=$(cat filename.txt)
echo -e ${string} | awk 'NR % 2 {print $2}
!(NR % 2) {
  args = $10" "$11" "$12" "$13" "$14" "$15
  cmd = "date -d \""args"\" \"+%d-%b-%Y\""
  cmd | getline expiry_date
  close(cmd)
  print expiry_date
}' > validitylist.txt

Thanks for helping out guys!