Parsing CSV records when a value is multiline - bash

Question

Source file looks like this:
"google.com", "vuln_example1
vuln_example2
vuln_example3"
"facebook.com", "vuln_example2"
"reddit.com", "stupidly_long_vuln_name1"
"stackoverflow.com", ""
I've been trying to get the output to be something like this but the line breaks seem to cause me no end of problems. I'm using a "while read line" job to do this because I do some processing on the columns (e.g Vulnerability count and url in this example). This is output into a jenkins job (yuk).
The basic summary of the problem is getting the linebreaks in the csv to be output into the third column while retaining the table structure. I've got a sort of weird example of the desired output below.
||hostname ||Vulnerability count|| Vulnerability list || URL ||
|google.com |3 |vuln_example1 |http://cve.com/vuln_example1|
| | |vuln_example2 |http://cve.com/vuln_example2|
| | |vuln_example3 |http://cve.com/vuln_example3|
|facebook.com |1 |vuln_example2 |http://cve.com/vuln_example2|
|reddit.com |1 |stupidly_long_vuln_name1 |http://cve.com/stupidly_long_vuln_name1|
|stackoverflow.com |0 | ||
Looking at this... I've got a feeling it might be easier by showing some code and example output.

Answer 1

Parsing your input with the command line below makes the problem easier (I'm assuming the inputs are correct):
perl -0777 -pe 's/([^"])\s*\n/\1 /g ; s/[",]//g' < sample.txt
This line invokes Perl to perform two regex substitutions:
s/([^"])\s*\n/\1 /g: This substitution removes an end of line if it doesn't terminate by a quote " (i.e. if a host entry, with all vulnerabilities isn't yet complete).
s/[",]//g removes all quotes and commas remaining.
For each host entry like this one:
"google.com", "vuln_example1
vuln_example2
vuln_example3"
You'll get:
google.com vuln_example1 vuln_example2 vuln_example3
Then you can assume for each line, you have an host and a set of vulnerabilities.
The given example below stores vulnerabilities in an array and loop through it, formatting and printing each line:
# Replace this by your custom function
# to get an URL for a given vulnerability
function get_vuln_url () {
# This just displays a random url for an non-empty arg
[[ -z "$1" ]] || echo "http://host/$1.htm"
}
# Format your line (see printf help)
function print_row () {
printf "%-20s|%5s|%-30s|%s\n" "$#"
}
# The perl line reformat
perl -0777 -pe 's/([^"])\s*\n/\1 /g ; s/[",]//g' < sample.txt |
while read -r line ; do
arr=(${line})
print_row "${arr[0]}" "$((${#arr[#]} - 1))" "${arr[1]}" "$(get_vuln_url ${arr[1]})"
#echo -e "${arr[0]}\t|$vul_count\t|${arr[1]}\t|$(get_vuln_url ${arr[1]})"
for v in "${arr[#]:2}" ; do
print_row " " " " "$v" "$(get_vuln_url ${arr[1]})"
done
done
Output:
google.com | 3|vuln_example1 |http://host/vuln_example1.htm
| |vuln_example2 |http://host/vuln_example1.htm
| |vuln_example3 |http://host/vuln_example1.htm
facebook.com | 1|vuln_example2 |http://host/vuln_example2.htm
reddit.com | 1|stupidly_long_vuln_name1 |http://host/stupidly_long_vuln_name1.htm
stackoverflow.com | 0| |
Update.
If you don't have Perl, and if your file doesn't have tabulations, you can use this command as a workaround instead:
tr '\n' '\t' < sample.txt | sed -r -e 's/([^"])\s*\t/\1 /g' -e 's/[",]//g' -e 's/\t/\n/g'
tr '\n' '\t' replaces all ends of line by tabulations
sed part acts like Perl line, except it deals with tabulations instead of ends of line and restores tabulations back to ends of line.