jenkins/files/jobs/_parameters.xml

{%- if job.param is defined %}
    <hudson.model.ParametersDefinitionProperty>
      <parameterDefinitions>
        {%- for param_name, param in job.param.iteritems() %}
        <hudson.model.{{ param.get('type', 'string')|capitalize }}ParameterDefinition>
          <name>{{ param_name }}</name>
          {%- if param.description is defined %}
          <description>{{ param.description }}</description>
          {%- else %}
          <description/>
          {%- endif %}
          {%- if param.get('type', 'string')|lower == "choice" %}
          <choices class="java.util.Arrays$ArrayList">
            <a class="string-array">
              {%- for choice in param.choices %}
              <string>{{ choice|e }}</string>
              {%- endfor %}
            </a>
          </choices>
          {%- endif %}
          {%- if param.default is defined %}
          <defaultValue>{{ param.get('default') }}</defaultValue>
          {%- else %}
          <defaultValue/>
          {%- endif %}
        </hudson.model.{{ param.get('type', 'string')|capitalize }}ParameterDefinition>
        {%- endfor %}
      </parameterDefinitions>
    </hudson.model.ParametersDefinitionProperty>
    {%- if job.discard is defined %}
     <jenkins.model.BuildDiscarderProperty>
          <strategy class="hudson.tasks.LogRotator">
            <daysToKeep>{{ job.discard.get('build',{}).get('keep_days',-1) }}</daysToKeep>
            <numToKeep>{{ job.discard.get('build',{}).get('keep_num',-1) }}</numToKeep>
            <artifactDaysToKeep>{{ job.discard.get('artifact',{}).get('keep_days',-1) }}</artifactDaysToKeep>
            <artifactNumToKeep>{{ job.discard.get('artifact',{}).get('keep_num',-1) }}</artifactNumToKeep>
          </strategy>
      </jenkins.model.BuildDiscarderProperty>
    {%- endif %}
{%- endif %}
{#-
  vim: syntax=jinja sw=2 ts=2
-#}