How to restrict only one parameter in jenkins pipeline

Question

I have the below pipeline script with string parameters. The Target parameter will fail if multiple comma separated inputs are provided in Jenkins. How can I restrict the Jenkins pipeline to accept just one value as parameter and not multiple comma separated values.

properties([
parameters([
    string(defaultValue: '', description: '', name: 'ID'),
    string(defaultValue: '', description: '', name: 'Target')
    ])
])

Answer 1

Extended Choice Parameter plugin is the way to go for such requirement. You need to select Extended Choice Parameter from the drop-down list as shown below:

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In Name text-box, assign a name. For example, Environment. This is the name with which you will be accessing all the values (dev1,dev2,...) that you will select while triggering the build. Now, in Simple Parameter Types section, you will see another drop-down with the name Parameter Type. Select Multi Select from that drop-down. Now, in Choose Source for Value section, enter the values (dev1,dev2,qa1,qa2,...) in Value box. Comma (,) is the default delimiter. Refer screenshot below:

enter image description here

Once you are done with the above settings, you will then have to access the selected option in your script (using variable assigned to Name as described above) and decide the course of action.