Querying a MongoDB documents in real-time - node.js

Question

I'm building a web application that will work with Big Data.
I will mine Twitter data using the Apache Storm, subsequently saving them in a MongoDB database.
At same time, this data has to be fetched via Node.js in real time and be sent via socket.io to my front-end.
Exist a way to querying MongoDB via Node.js in real time?
Thanks.

Answer 1

I am working on a project with mongoDB, I used the mongodb npm module to query the database in real time.
First I get a list of collections which are in my database:
//My server controller page
var MongoClient = require('mongodb').MongoClient
, assert = require('assert');
exports.getCollections = function(req,res){
mongoose.connection.db.collectionNames(function(err, names) {
if (err){
console.log(err)
} else {
res.status(200).send({collections: names});
}
});
};
On the front end, I do an Angular ng-repeat to list my collections, then when I click on the collection name, I run the following code:
MongoClient.connect(url, function (err, db) {
assert.equal(null, err);
var collection = db.collection(req.body.collName);
collection.find({}).limit(req.body.limit).toArray(function (err, docs) {
if (err) {
console.log(err)
} else {
res.status(200).send({r: docs, count: docs.length});
db.close();
}
})
});
Here is my client side angular code:
//get the collection list upon page load
$http.get('collections')
.success(function(c){
$scope.collList = c.collections;
})
.error(function(err){
$scope.error = err;
});
//function run when collection is selected
$scope.doFind = function(coll){
$scope.collViewing = coll;
$http.post('/basicfind',{collName: coll,limit:$scope.limiter})
.success(function(data){
$scope.results = data.r;
$scope.countOfResults = data.count;
})
.error(function(err){
$scope.error = err.message;
});
};
Hope that helps, let me know if you need me to share any more code