Split command output into separate variables - bash

Question

I'm trying to use a bash script with macos time machine.
I'm trying to read the properties of the time machine backup destinations and then split the destinations into variables if there are multiple destinations.
from there I can use the ID to make a backup.
I'm having trouble splitting the output into their own variables.
rawdstinfo=$(tmutil destinationinfo)
echo "$rawdstinfo"
> ==================================================
Name : USB HDD
Kind : Local
Mount Point : /Volumes/USB HDD
ID : 317BD93D-7D90-494C-9D5F-9013B25D1345
====================================================
Name : TM TEST
Kind : Local
Mount Point : /Volumes/TM TEST
ID : 4648083B-2A11-42BC-A8E0-D95917053D27
I was thinking of counting the ================================================== and then trying to split the variable based on them but i'm not having any luck.
any help would be greatly appreciated.
Thanks
PS:
to make it clear what i would like to achieve, I would like to send each destination drive to an object. From there I can compare the mount point names (which has been selected earlier in the script), to then get the "destination ID" within that object so I can then use it with the other tmutil commands such as
#start a TM backup
sudo tmutil startbackup --destination $DESTINATIONID
#remove Migration HDD as a destination
sudo tmutil removedestination $DESTINATIONID

Answer 1

I like to use awk for parsing delimited flat files. I copied the tmutil output from your question and pasted it into a file I named testdata.txt since I'm not doing this on a Mac. Make sure the number of equal signs in the record separators actually match what tmutil produces.
Here is the awk portion of the solution which goes into a file I named timemachine_variables.awk:
function ltrim(s) { sub(/^[ \t\r\n]+/, "", s); return s }
function rtrim(s) { sub(/[ \t\r\n]+$/, "", s); return s }
function trim(s) { return rtrim(ltrim(s)); }
BEGIN {
RS="====================================================\n";
FS=":|\n"
}
{
i=FNR-1
}
(FNR>1 && $1 ~ /Name/) {print "Name["i"]="trim($2)}
(FNR>1 && $3 ~ /Kind/) {print "Kind["i"]="trim($4)}
(FNR>1 && $5 ~ /Mount Point/) {print "Mount_Point["i"]="trim($6)}
(FNR>1 && $7 ~ /ID/) {print "ID["i"]="trim($8)}
The functions at the beginning are to trim leading or trailing white spaces off any fields. I split the records based on the equals sign separators and the fields based on the colon ":" character. FNR is gawk's internal variable for the current record number that we're looking at. Since the output apparently begins with a bar of equal signs, the first record is empty so I am using FNR > 1 as a condition to exclude it. Then I have gawk print code which will become array assignments for bash. In your example, this should be gawk's output:
$ gawk -f timemachine_variables.awk testdata.txt
Name[1]=USB HDD
Kind[1]=Local
Mount_Point[1]=/Volumes/USB HDD
ID[1]=317BD93D-7D90-494C-9D5F-9013B25D1345
Name[2]=TM TEST
Kind[2]=Local
Mount_Point[2]=/Volumes/TM TEST
ID[2]=4648083B-2A11-42BC-A8E0-D95917053D27
In your BASH script, declare the arrays from the gawk script's output:
$ declare $(gawk -f timemachine_variables.awk testdata.txt)
You should now have BASH arrays for each drive:
$ echo ${ID[2]}
4648083B-2A11-42BC-A8E0-D95917053D27
UPDATE: The original awk script that I posted does not work on the Mac because BSD awk does not support multi-character separators. I'm leaving it here because it works for gawk, and comparing the two scripts may help others who are looking for a way to achieve multi-character separator behavior in BSD awk.
Instead of changing the default record separator which is the end of the line, I set my own counter of i to 0, and then increment it every time the whole record starts and ends with one or more equal signs. Since awk now views each line as its own record and the field separator is still ":", the name we are trying to match is always in $1 and the value is always in $2.
function ltrim(s) { sub(/^[ \t\r\n]+/, "", s); return s }
function rtrim(s) { sub(/[ \t\r\n]+$/, "", s); return s }
function trim(s) { return rtrim(ltrim(s)); }
BEGIN {
FS=":";
i=0;
}
($0 ~ /^=+$/) {i++;}
($1 ~ /Name/) {print "Name["i"]="trim($2)}
($1 ~ /Kind/) {print "Kind["i"]="trim($2)}
($1 ~ /Mount Point/) {print "Mount_Point["i"]="trim($2)}
($1 ~ /ID/) {print "ID["i"]="trim($2)}