我正在尝试从弹性搜索查询返回结果。这是我的网页
<!DOCTYPE html>
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
</head>
<script>
$(document).ready(function() {
$('#ping-button').click(function(e) {
e.preventDefault();
var val;
$.ajax({
type: 'POST',
url: 'http://localhost:6002/esPingTest',
success: function(data){
alert(data);
alert("Yay");
val=data;
document.getElementById("demo").innerHTML = val;
},
error: function(){
alert("Nay");
}
});
});
});
</script>
<body>
<center>
<button id='ping-button'>Ping</button>
<br><br>
<p id="demo"></p>
</center>
</body>
</html>
所以我有一个按钮，当我点击它时，它应该去esPingTest方法。
这是我的 app.js
var express = require('express');
var app = express();
var cfenv = require('cfenv');
var bodyParser = require('body-parser');
var port = (process.env.VCAP_APP_PORT || 3000);
var host = (process.env.VCAP_APP_HOST || 'localhost');
// Create application/x-www-form-urlencoded parser
var urlencodedParser = bodyParser.urlencoded({ extended: false })
app.use(express.static('elastic'));
var appEnv = cfenv.getAppEnv();
//start server on the specified port and binding host
var server = app.listen(appEnv.port, '0.0.0.0', function() {
console.log("server starting on " + appEnv.url);
})
app.get('/index.html', function (req, res) {
res.sendFile( __dirname + "/" + "index.html" );
})
app.post('/esPingTest', urlencodedParser, function (req, res) {
console.log("Ping");
docs = getEsDocs()
console.log(docs)
res.end(JSON.stringify(docs));
})
function getEsDocs()
{
var elasticsearch = require('elasticsearch');
var client = elasticsearch.Client({
host: 'localhost:9200',
log: 'trace'
});
client.ping({
// ping usually has a 3000ms timeout
requestTimeout: Infinity,
// undocumented params are appended to the query string
hello: "elasticsearch!"
}, function (error) {
if (error) {
console.trace('Elasticsearch cluster is down!');
return "Error:Elasticsearch cluster is down!"
} else {
console.log('All is well');
ff = getmeres(client);
console.log("ping")
console.log(ff)
return ff
//alert("YAY");
}
});
function getmeres(client)
{
var xox =
client.search({
index: 'researchtest',
body: {
"aggs": {
"docs": {
"terms": {
"field": "DocumentID"
}
}
}
}
}, function (error, response) {
if (error) {
console.trace('Search query failed');
return "Error:Search query failed"
} else {
console.log('All is well');
d=response;
console.log("getmeres");
x=showdocs(d);
console.log("inner xo is"+xo);
var xo=x;
console.log("inner xo is"+xo);
}
});
console.log("outer xox is"+xox);
return xox;
}
function showdocs(d){
da=d.hits.hits
var docs=[]
for (i=0;i<da.length;i++)
{
docs.push(da[i]["_source"]["DocumentID"]);
}
console.log("showdocs")
console.log(docs)
return docs;
}
}
所以我showdocs()从函数的 else 条件中client.search调用函数
最后，我没有看到由于以下原因而返回的任何值return xo
这是我得到的结果
getmeres
showdocs
[ '12',
'12',
'23' ]
inner xo is[object Object]
inner xo 12,12,23
分配后如何取回 xo 的值xo=x？
为什么最后一个console.log("outer xox is"+xox);根本没有打印出来？
我不知道如何将结果返回到我的网页
编辑
感谢@peteb 的回答。现在这是我的电话
var ff = getmeres(client, function getmeresResult(err, result){
if (err) return err;
console.log("Got res "+result);
return result;
});
console.log("ping")
console.log(ff)
return ff;
getmeres正如你所建议的那样。现在我明白了
showdocs [ '12', '12', '23' ] 得到 res 12,12,23
这太棒了！但它仍然没有将值分配回ff. 我需要ff返回getEsDocs
getEsDocs我应该以同样的方式打电话getmeres吗？有回调？如果是这样，以下调用是否有效
docs = getEsDocs(function getDocResult(err, result){
if (err) return err;
console.log("Got doc "+result);
return result;
})
console.log(docs)
res.end(JSON.stringify(docs));
差不多好了
再次感谢，我想我快到了
这是我的第一个电话
getEsDocs(function getDocResult(err, result){
if (err) return err;
console.log("Got doc "+result);
res.end(JSON.stringify(result));
return result;
})
这是我的第二个电话
function getEsDocs(callback)
{
var elasticsearch = require('elasticsearch');
var client = elasticsearch.Client({
host: 'localhost:9200',
log: 'trace'
});
client.ping({
// ping usually has a 3000ms timeout
requestTimeout: Infinity,
// undocumented params are appended to the query string
hello: "elasticsearch!"
}, function (error) {
if (error) {
console.trace('Elasticsearch cluster is down!');
return "Error:Elasticsearch cluster is down!"
} else {
console.log('All is well');
return callback(null, getmeres(client, function getmeresResult(err, result){
if (err) return err;
console.log("Got res "+result);
return result;
}));
}
});
它仍然打印
showdocs
[ '12',
'12',
'23' ]
Got res 12,12,23
我错过了什么？
几乎
所以这就是我所拥有的，正如你所建议的
app.post('/esPingTest', urlencodedParser, function (req, res) {
console.log("Ping");
getEsDocs(function getEsDocsResult(err, result) {
if (err) return res.status(400).json(result);
console.log("Got doc"+result)
return res.status(200).json(result);
});
});
function getEsDocs(callback)
{
var elasticsearch = require('elasticsearch');
var client = elasticsearch.Client({
host: 'localhost:9200',
log: 'trace'
});
client.ping({
// ping usually has a 3000ms timeout
requestTimeout: Infinity,
// undocumented params are appended to the query string
hello: "elasticsearch!"
}, function (error) {
if (error) {
console.trace('Elasticsearch cluster is down!');
return "Error:Elasticsearch cluster is down!"
} else {
console.log('All is well');
return callback(null, getmeres(client, getmeresResult));
function getmeresResult(err, result)
{
if (err) return err;
console.log("Got res "+result);
return result;
}
}
});
}
但我仍然没有看到最终的回报！你能看出有什么不对吗？
所以基本上这个回报
if (err) return err;
console.log("Got res "+result);
return result;
不工作！