Question

我使用javascript和REST API查询Neo4j数据库，按名称搜索节点。提交查询后，firebug控制台显示错误400“错误请求”，其中包含以下内容： “message”：“你必须提供'查询'参数。”， “exception”：“BadInputException”，

以下是我用来提交查询的功能。当警告“search_query”时，语法似乎是正确的，并且字符串化的“queryObject”是有效的JSON。谢谢你帮助我理解为什么会这样，以及如何解决它。

~~~~ 注意：只需使用以下方法即可使用：

data:{
            "query":"start n  = node(*) WHERE n.name =~ '" + search_name + ".*' return n order by n.name asc",
            "params":{}
      },

~~~~

<script>
function name_search()
{
var queryObject = new Object; //declare object to hold query and parameters

var search_name = document.getElementById("name_search").value; //get node name search term from user input 
search_name = "'"+search_name+".*'"; //append ".*" to search on Regular Expression
//alert("search: " + search_name);

search_query = 'start n  = node(*) WHERE n.name =~ ' + search_name + ' return n order by n.name asc'; //create query

queryObject.query = search_query; //insert query string in queryObject

queryObject.params = {}; //empty object = no query parameters

alert(JSON.stringify(queryObject));

var restServerURL = "http://localhost:7474/db/data"; //local copy on windows machine

$.ajax({
      type:"POST",
      url: restServerURL + "/cypher",
      accepts: "application/json",
      dataType:"json",
      data:JSON.stringify(queryObject), //convert queryObject to JSON for inserting into database
      success: function(data, xhr, textStatus){
        //process query results
        $('#query_results').empty(); //clear div that will contain results
        var length = data.data.length; //capture number nodes returned
        //alert("number of nodes: " + length);
        $('#query_results').append($('<p>').html('number of nodes: ' + length + '<br />'));

        for (var u = 0; u < length; u++){
            var num_props = Object.keys(data.data[u][0].data).length;//get number of node properties from length of data.data.data child property in JSON
            var node_num = data.data[u][0].self;//get node number from data.data.self and 
            node_num = node_num.replace(restServerURL+"/node/","");//strip restServerURL+"/node/" from result
            //alert("Node "+ node_num + " has: "+ num_props + " properties");
            $('#query_results').append($('<p>').html('Node '+ node_num + ' has: '+ num_props + ' properties' + '<br />'));
            for (var v = 0; v < num_props; v++){
                var prop = (Object.keys(data.data[u][0].data))[v];//get property name key
                var val = data.data[u][0].data[prop]; //use property name to get value
                //alert("prop: " + prop +" value: " + val);
                $('#query_results').append($('<p style="text-indent: 1em;">').html('prop: ' + prop +' value: ' + val + '<br />'));
            }               
        };
      },
      error:function(jqXHR, textStatus, errorThrown){
                       alert(errorThrown);
      }
});

}//end of search for node by name
</script>

Answer 1

数据类型json自己进行转换，因此您必须在那里提供对象。正如你所注意到的那样。

我强烈建议您在查询中使用n.name =~{search_name}参数，然后传递

{query: ...,params: { search_name: search_name+".*"}}

错误400“错误请求”neo4j REST API javascript

1 个答案: