How to extract value from a string in shell script?

Question

I have this environment variable

echo $DT_CUSTOM_PROP

returns

APPCODE=IK22 ENVIRONMENT=DEV APPLICATION=xxxxx-xxxxx-xxxxx-xxxxx ANOTHERKEY=ANOTHERVALUE

How can I get APPLICATION from it?

So that if I do echo $APPLICATION I get xxxxx-xxxxx-xxxxx-xxxxx

what does `echo "$DT_CUSTOM_PROP"` return? (ie. are the spaces in your original output really spaces?) — jhnc, Jun 27 '22 at 16:20
The same: `APPCODE=IK22 ENVIRONMENT=DEV APPLICATION=xxxxx-xxxxx-xxxxx-xxxxx ANOTHERKEY=ANOTHERVALUE ` — Amin Ba, Jun 27 '22 at 16:23
Is `DT_CUSTOM_PROP` set by something you trust? If so, it looks like you could do: `APPLICATION=$(eval $DT_CUSTOM_PROP; echo $APPLICATION)` or even just `eval $DT_CUSTOM_PROP` — jhnc, Jun 27 '22 at 16:25
That works. Thanks! What I want to get only the application? — Amin Ba, Jun 27 '22 at 16:29

score 0 · Answer 1 · answered Jun 27 '22 at 17:06

Given:

DT_CUSTOM_PROP='APPCODE=IK22 ENVIRONMENT=DEV APPLICATION=xxxxx-xxxxx-xxxxx-xxxxx ANOTHERKEY=ANOTHERVALUE'

You can do it with parameter expansion in a 2-step process:

tmp=${DT_CUSTOM_PROP#*APPLICATION=}
application=${tmp%% *}    # ==> xxxxx-xxxxx-xxxxx-xxxxx

Or with bash regex matching

if [[ $DT_CUSTOM_PROP =~ "APPLICATION="([^[:blank:]]+) ]]; then
    application=${BASH_REMATCH[1]}
else
    application="not found"
fi

1 Answers1