I am trying to extract part of url using bash regex . from below mentioned URL i just want to extract 124, which will always be between two hyphens .
http://abc-124-001.portal-ex.xyz-xyz.com:8091/
i tried doing following but i am looking for any better options to do this in one line
f=http://abc-124-001.portal-ex.xyz-xyz.com:8091/
f=${f#*-}
echo ${f%%-*}
op: 124
can this be done in one line or in any better way??
You can use cut:
#!/bin/bash
s='htt''p://abc-124-001.portal-ex.xyz-xyz.com:8091/'
id=$(cut -d'-' -f2 <<< "$s")
echo "$id"
See the online demo.
id=$(cut -d'-' -f1,2 <<< 'htt''p://abc-124-001.portal-ex.xyz-xyz.com:8091/') and then echo "${id/http:\/\//}", or use id=$(sed 's,.*://\([^-]*-[^-]*\).*,\1,' <<< 'htt''p://abc-124-001.portal-ex.xyz-xyz.com:8091/') (demo).I think your approach is not bad. Alternatively this can also be done using a regexp:
[[ $f =~ -([^-]+)- ]]
echo ${BASH_REMATCH[1]}
It needs only "one step" for the extraction, while your approach needs two. However your glob patterns are simpler than my regex, so it is a matter of taste what you consider simpler.
Note that I didn't treat the case when the pattern does not match at all, simply since you also did not care about this case. It is trivial to add some error handling if you want to.
You can use regex matching:
if [[ $f =~ -([0-9]+) ]] ; then
n=${BASH_REMATCH[1]}
echo $n
else
echo Cannot match in $f >&2
exit 1
fi
Or maybe ^[^-]+-([0-9]+) to not match 124 in
http://abc-a-124-001.portal-ex.xyz-xyz.com:8091/
# ~
Not really a one-liner but almost:
$ f=http://abc-124-001.portal-ex.xyz-xyz.com:8091/
$ arr=(${f//-/ })
What you look for is arr[1]:
$ echo ${arr[1]}
124
Using read with IFS
$ f=http://abc-124-001.portal-ex.xyz-xyz.com:8091/
$ IFS='-' read -ra parts <<< $f
$ echo "${parts[1]}"
124
$ declare -p parts
declare -a parts=([0]="http://abc" [1]="124" [2]="001.portal" [3]="ex.xyz" [4]="xyz.com:8091/")
Try awk:
$ echo "http://abc-124-001.portal-ex.xyz-xyz.com:8091/" | awk -F"-" ' { print $2 } '
124
one-linerthen consider:f=${f#*-}; echo ${f%%-*}