code: function processAdd(cmd) {
  
    doc = cmd.solrDoc;  // org.apache.solr.common.SolrInputDocument
    id = doc.getFieldValue("id");
    logger.info("update-script#processAdd: id=" + id);
  
  // Set a field value:
  //  doc.setField("foo_s", "whatever");
  
  // Get a configuration parameter:
  //  config_param = params.get('config_param');  // "params" only exists if processor configured with <lst name="params">
  
  // Get a request parameter:
  // some_param = req.getParams().get("some_param")
  
  // Add a field of field names that match a pattern:
  //   - Potentially useful to determine the fields/attributes represented in a result set, via faceting on field_name_ss
  //  field_names = doc.getFieldNames().toArray();
  //  for(i=0; i < field_names.length; i++) {
  //    field_name = field_names[i];
  //    if (/attr_.*/.test(field_name)) { doc.addField("attribute_ss", field_names[i]); }
  //  }
  
  }
docs: /*
  This is a basic skeleton JavaScript update processor.
  
  In order for this to be executed, it must be properly wired into solrconfig.xml; by default it is commented out in
  the example solrconfig.xml and must be uncommented to be enabled.
  
  See http://wiki.apache.org/solr/ScriptUpdateProcessor for more details.