Looping through While read separates the string in shell script - linux

Question

I have json file named as test.json, I want to parse the value of id, name and not_after then put in condition to verify the not_after should not exceed before 60 days.
vi test.json
{
"id" : 10001,
"name" : "Test Client Name",
"type" : "PKCS12",
"provider" : "SunJSSE",
"password" : "1111111",
"url" : "data:application/xxxx-xxx,1234567890987",
"entry" : [ {
"alias" : "example.com,
"type" : "PrivateKeyEntry",
"algorithm" : "EC",
"subject" : "C=CA, ST=ON, L=Toronto, O=Techonology, OU=example, CN=example.com",
"issuer" : "C=US, O=example Lab, CN=ExampleCA",
"not_before" : "Fri, 21 Aug 2020 19:44:26 GMT",
"not_after" : "Sun, 21 Aug 2022 19:44:26 GMT",
"tn_auth_list" : [ {
"spc" : "AA001"
} ]
} ],
"created_date" : "Thu, 20 Aug 2020 04:38:16 GMT"
}{
"id" : 10002,
"name" : "client-02",
"type" : "PKCS12",
"provider" : "SunJSSE",
"password" : "1111111",
"url" : "data:application/xxxx-xxx,1234567890987",
"customer_id" : 12002,
"entry" : [ {
"alias" : "example.com",
"type" : "PrivateKeyEntry",
"algorithm" : "EC",
"subject" : "C=US, ST=CA, L=San Ramon, O=Five9, OU=example, CN=example.com",
"issuer" : "C=US, O=example Lab, CN=ExampleCA",
"not_before" : "Tue, 2 Jun 2020 12:15:36 GMT",
"not_after" : "Thu, 2 Jun 2022 12:15:36 GMT",
"tn_auth_list" : [ {
"spc" : "ZZ001"
} ]
} ],
"created_date" : "Mon, 14 Dec 2020 21:42:35 GMT"
}
The output of jq could not be consider as one string in while read, so that condition not working properly, If i give only .entry[].not_after I can get the not_after output perfectly. Need some help that while read should not break the names string and it should consider the name as single string.
cat test.json | jq -r '.name, .entry[].not_after' | while read name expirydate; do
echo certname=$name
echo expiryday=$expirydate
not_after="${expirydate}"
echo expirydate=$not_after
condition=$(( $(date +%s) + $((60*24*60*60)) ))
echo condition=$condition
not_after_in_seconds=$(date -d "$not_after" +%s)
# echo not_after_in_seconds: $not_after_in_seconds
# echo not_after_in_date: $(date -d #$not_after_in_seconds)
if [ $condition -ge $not_after_in_seconds ]
then
echo Certificate name : $certname will be expire in 60 days, Expiration Date = $not_after
else
echo No issues for 60 days
fi
done
output:
certname=Test
expiryday=Client Name
expirydate=Client Name
condition=1661241563
date: invalid date 'Client Name'
./dummy.sh: line 15: [: 1661241563: unary operator expected
No issues for 60 days
certname=Sun,
expiryday=21 Aug 2022 19:44:26 GMT
expirydate=21 Aug 2022 19:44:26 GMT
condition=1661241563
Certificate name : will be expire in 60 days, Expiration Date = 21 Aug 2022 19:44:26 GMT
certname=client-02
expiryday=
expirydate=
condition=1661241563
Certificate name : will be expire in 60 days, Expiration Date =
certname=Thu,
expiryday=2 Jun 2022 12:15:36 GMT
expirydate=2 Jun 2022 12:15:36 GMT
condition=1661241563
Certificate name : will be expire in 60 days, Expiration Date = 2 Jun 2022 12:15:36 GMT
Expected output:
Certificate name : Test Client Name will be expire in 60 days, Expiration Date = 21 Aug 2022 19:44:26 GMT
Certificate name : client-02 will be expire in 60 days, Expiration Date = 2 Jun 2022 12:15:36 GMT

Answer 1

We can use | #sh to quote a JSON array for evaluation by the shell:
jq -r '[.name, .entry[].not_after ] | #sh' test.json
Gives:
'Test Client Name' 'Sun, 21 Aug 2022 19:44:26 GMT'
'client-02' 'Thu, 2 Jun 2022 12:15:36 GMT'
Now we have a list of four separate words. We can use eval to store this in a bash array.
An example script:
#!/bin/bash
eval "a=($(jq -r '[.name, .entry[].not_after ] | #sh'))"
for ((i=0; i<${#a[#]}; i+=2)); do
name=${a[i]} expiry=${a[i+1]}
expiry_epoch=$(date -d "$expiry" +%s)
now_epoch=$(date +%s)
days_left=$(( (expiry_epoch - now_epoch) / 86400 ))
if ((days_left == 0)); then
echo "$name: warning: expires today"
elif ((days_left < 0)); then
echo "$name: EXPIRED $((days_left*-1)) days ago"
elif ((days_left < 60)); then
echo "$name: warning: expires in $days_left" days
else
echo "$name: $days_left days left"
fi
done
Use like: expiry-script < test.json
Correctly calculating days remaining isn't always simple. This script truncates the current day (ie. 4.9 days becomes 4 days). That may be desired, but it's also wrong one hour per year, if the timezone has daylight savings time. DST causes a 23 hour day, meaning a day is truncated when it shouldn't be.
One alternative, which doesn't have this problem, is to round up or down to the nearest day:
printf -v days_left %.0f \
"$(echo "scale=1; ($expiry_epoch - $now_epoch)/86400" | bc)"
This is a different approach. Rounding does avoid the DST issue though.