How to use jenkins version number plugin in pipeline - jenkins

Question

I am using version number jenkin plugin in Jenkins ver. 2.107.2. below pipeline code is not working. any help to fix this issue?
pipeline code
pipeline {
agent any
stages {
stage('Pre-Build') {
steps {
sh 'echo Building Docker'
def tag = VersionNumber (versionNumberString: '${BUILD_DATE_FORMATTED, "yyyyMMdd"}-develop-${BUILDS_TODAY}')
}
}
}
}
Error:
Running in Durability level: MAX_SURVIVABILITY
org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
WorkflowScript: 8: Expected a step # line 8, column 1.
def tag = VersionNumber (versionNumberString: '${BUILD_DATE_FORMATTED, "yyyyMMdd"}-develop-${BUILDS_TODAY}')
^
1 error
at org.codehaus.groovy.control.ErrorCollector.failIfErrors(ErrorCollector.java:310)
at org.codehaus.groovy.control.CompilationUnit.applyToPrimaryClassNodes(CompilationUnit.java:1085)
at org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(CompilationUnit.java:603)
at org.codehaus.groovy.control.CompilationUnit.processPhaseOperations(CompilationUnit.java:581)
at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:558)
at groovy.lang.GroovyClassLoader.doParseClass(GroovyClassLoader.java:298)
at groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:268)
at groovy.lang.GroovyShell.parseClass(GroovyShell.java:688)
at groovy.lang.GroovyShell.parse(GroovyShell.java:700)
at org.jenkinsci.plugins.workflow.cps.CpsGroovyShell.doParse(CpsGroovyShell.java:131)
at org.jenkinsci.plugins.workflow.cps.CpsGroovyShell.reparse(CpsGroovyShell.java:125)
at org.jenkinsci.plugins.workflow.cps.CpsFlowExecution.parseScript(CpsFlowExecution.java:560)
at org.jenkinsci.plugins.workflow.cps.CpsFlowExecution.start(CpsFlowExecution.java:521)
at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:325)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:429)
Finished: FAILURE
this link How to use jenkins version number plugin in Jenkinsfile? has answer but not working for me.

Answer 1

You are using the declarative Pipeline, which has some restrictions regarding the commands which can be run inside a stage.
Take a look at the syntax guide for declarative pipelines.
You can either use the scripted pipeline or declare the variable in an environment block:
environment {
tag = VersionNumber(versionNumberString: '${BUILD_DATE_FORMATTED,"yyyyMMdd"}-develop-${BUILDS_TODAY}');
}
and later use it as $tag in your pipeline.