The code doesn't work. error 500 help me!

Elastic Stack Elasticsearch
1 
<script type="text/javascript">
var postData = {

"query" : {
"query_string" : {
"query" : "about"
}
}
};

$.getJSON('http://localhost:9200/my_couch_db/my_couch_db/
_search',postData,
function(data) {
var infoHTML='

@hits.total'+date.hits.total+'.@

';
$('#info').html(infoHTML); 
    }
  );

</script>
helio!

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