How to use stored certificate in Jenkins declarative pipeline?

Question

I have a stored certificate in Jenkins, and I need to use it in a pipelinebuild job, but the problem is it appears the Pipeline can't use certificates:

trying to use:

    environment {
        KEY = credentials('mycert')
    }

results in:

ERROR: No suitable binding handler could be found for type com.cloudbees.plugins.credentials.impl.CertificateCredentialsImpl. Supported types are StandardUsernamePasswordCredentials,FileCredentials,StringCredentials,SSHUserPrivateKey.

How do I get around this and use that stored cert in a pipeline? There has to be a way otherwise why would storing certs as credentials even be possible.. would be useless to store something without ever being able to use it.

Answer 1

Some credential types cannot be bound directly in an environment section. From the docs :

If you need to set credentials in a Pipeline for anything other than secret text, usernames and passwords, or secret files - i.e SSH keys or certificates, then use Jenkins' Snippet Generator feature, which you can access through Jenkins' classic UI.

So the generator would give you something looking like this:

withCredentials([certificate(aliasVariable: '', credentialsId: 'myCert', keystoreVariable: 'CERT', passwordVariable: '')]) {
    // some block
}

Answer 2

I usually set the credential NAME into an environment variable

environment {
    CERT = 'mycert'
}

Then I can use that name where ever I need it

withCredentials([usernamePassword(credentialsId: "${env.CERT}",
                                  passwordVariable: 'CERT_PASSWORD',
                                  usernameVariable: 'CERT_USER')]) {
    // Do things needing environment variables
}

or

checkout(poll: false,
         scm: [
               $class: 'GitSCM',
               userRemoteConfigs: [[credentialsId: "${env.CERT}", 
                                   url: 'https://code.example.org/somerepo']]
               ])