How to pass variables from Jenkinsfile to shell command

Question

I want to use a variable which I am using inside of my Jenkinsfile script, and then pass its value into a shell script execution (either as an environment variable or command line parameter).

But the following Jenkinsfile:

for (i in [ 'a', 'b', 'c' ]) {
    echo i
    sh 'echo "from shell i=$i"'
}

Gives the output:

a
from shell i=
b
from shell i=
c
from shell i=

Desired output is something like:

a
from shell i=a
b
from shell i=b
c
from shell i=c

Any idea how to pass the value of i to the shell scipt?

Edit: Based upon Matt's answer, I now use this solution:

for (i in [ 'a', 'b', 'c' ]) {
    echo i
    sh "i=${i}; " + 'echo "from shell i=$i"'
}

The advantage is, that I don't need to escape the " in the shell script.

Matthew Schuchard · Accepted Answer · 2017-04-07T16:15:39.933

Your code is using a literal string and therefore your Jenkins variable will not be interpolated inside the shell command. You need to use " to interpolate your variable inside your strings inside the sh. ' will just pass a literal string. So we need to make a few changes here.

The first is to change the ' to ":

for (i in [ 'a', 'b', 'c' ]) {
  echo i
  sh "echo "from shell i=$i""
}

However, now we need to escape the " on the inside:

for (i in [ 'a', 'b', 'c' ]) {
  echo i
  sh "echo \"from shell i=$i\""
}

Additionally, if a variable is being appended directly to a string like you are doing above ($i onto i=), we need to close it off with some curly braces:

for (i in [ 'a', 'b', 'c' ]) {
  echo i
  sh "echo \"from shell i=${i}\""
}

That will get you the behavior you desire.

THANK YOU! I wish I could upvote this 1000 times! The single quote vs. double quotes was my issue! — GCB613, Nov 01 '21 at 23:40

score 27 · Answer 2 · edited Dec 03 '20 at 08:24

27

Extension to Matts answer: For multi-line sh scripts use

sh """
  echo ${paramName}
"""

instead of

sh '''
  echo ${paramName}
'''

edited Dec 03 '20 at 08:24

codester

117
2
9

answered Aug 29 '17 at 13:51

TouDick

1,262
12
18

post { always { script { def body sh( script: ''' cat "/tmp/output.text" body=$( – Ashish Karpe Jan 06 '23 at 11:03
I am getting in email Sending Body null..... this means variable from sh scope is not outside it so how can I make this work ? – Ashish Karpe Jan 06 '23 at 11:04
Most probably the problem is in non escaped $ which is being resolved by groovy before value is given to script/shell. Try using body=\$( – TouDick Jan 07 '23 at 22:23
or alternatively use ' or ''' instead of "/""". Then the string will be given to shell as is without trying to resolve any values inside. – TouDick Jan 07 '23 at 22:26

score 0 · Answer 3 · answered Jan 08 '17 at 23:36

0

try this:

for (i in [ 'a', 'b', 'c' ]) {
    echo i
    sh '''
    echo "from shell i=$i"
    '''
}

answered Jan 08 '17 at 23:36

chenchuk

5,324
4
34
41

i cant check, but also try to surround the var like this ${i} – chenchuk Jan 08 '17 at 23:39
3

Both won't work. Checking groovy syntax, the difference between `'` and `'''` is just single line string versus multiline string. – Joe Jan 09 '17 at 15:22
3

I believe `sh """` would work. i.e. triple double-quotes instead of triple single-quotes – Simon Forsberg Oct 29 '17 at 20:59

score 0 · Answer 4 · edited Oct 30 '22 at 02:38

0

For multi-line, this should also work:

for (i in [ 'a', 'b', 'c' ]) {
    echo i
    sh '''
        VAR1="'''+i+'''"
        echo $VAR1
    '''
}

edited Oct 30 '22 at 02:38

James Risner

5,451
11
25
47

answered Oct 28 '22 at 21:16

imercuryous

1

How to pass variables from Jenkinsfile to shell command

4 Answers4

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