How do I send a Mongo Document back to the front end? - mongodb

Question

//router
app.get('/retrieve_report', function(req, res) {
var retrieved = retrieve_report(req, res);
res.render('retrieve_report.ejs', {
'report' : retrieved
});
});
//Load up the report model
var Report = require('../models/report');
console.log('Report ' + Report.schema);
//expose this function to our app using module.exports
//query
module.exports = function(req, res) {
//console.log('param ' + res.send);
var query = Report.findById(req.param('id'), function(err, doc) {
if(err) {
throw err;
}
else {
console.log('doc ' + JSON.stringify(doc));
res.send(doc);
}
});
}
//app.js
var retrieve_report = require('./config/retrieve_report');//which is the above code
I want to return the document to the router so that I can put its information into my view. I tried "res.json(doc), but that gave me the error, "throw new Error('Can\'t set headers after they are sent.');" Everyone says to use a callback function, but aren't I using a callback function here?

Answer 1

As your error says:
but that gave me the error, "throw new Error('Can\'t set headers after they are sent.');"
Means you are trying to send data the twice.
Sample code:
app.get('/retrieve_report', function(req, res) {
var query = Report.findById(req.param('id'), function(err, doc) {
if(err) {
throw err;
}
else {
console.log('doc ' + JSON.stringify(doc));
res.send(doc);
}
});
This should work..