groovy: MissingPropertyException: No such property: - jenkins

Question

I am facing an issue when shell command is returning non existent value because output produces no value as env.version == '1.0.0.232'-->false, does not exist in pypy server.
but when env.version == '1.0.0.23'--> true, does exist in pypy server, code proceed as normal.
Jenkins code:
pipeline {
agent { label 'master' }
parameters {
string(defaultValue: 'DEV', description: '', name: 'ENV', trim: true)
string(defaultValue: 'sys', description: '', name: 'platform_type', trim: true)
string(defaultValue: 'server2', description: '', name: 'dev_app_host', trim: true)
string(defaultValue: 'server1', description: '', name: 'dev_xbar_host', trim: true)
string(defaultValue: '1.0.0.23', description: '', name: 'VERSION', trim: true)
booleanParam(defaultValue: false, description: 'force build if possible', name: 'force_build')
}
environment {
}
stages {
stage('build') {
steps {
script {
try{
try{
def version_exists = sh(script: "ssh -o StrictHostKeyChecking=no ansible#pip_server ls /var/pypi/packages/dev/ | grep ${env.app_module_name} | grep ${env.VERSION}" , returnStdout: true) ?: 'no_files_found'
echo version_exists
echo version_exists.inspect()
echo version_exists.dump()
} catch(e){
echo "inner exception: ${e}"
}
} catch (e) {
echo "outer exception: ${e}"
currentBuild.result = 'FAILURE'
}
}
}
}
}
}
Jenkins relevant long:
+ grep 1.0.0.232
+ grep dvmt_event_processor
+ ssh -o StrictHostKeyChecking=no ansible#pip_server ls /var/pypi/packages/dev/
[Pipeline] echo
inner exception: hudson.AbortException: script returned exit code 1
[Pipeline] echo
outer exception: groovy.lang.MissingPropertyException: No such property: version_exists for class: groovy.lang.Binding
PS: can the shell command be improved upon?

Answer 1

grep returns status code 1 when it finds no matching lines. Jenkins interprets a non-0 status as the script failing, so it throws a hudson.AbortException rather than assigning the output to version_exists.
Try something like this:
def version_exists = sh( " ... | grep ${env.VERSION} || echo not_found", returnStdout: true)