mongodb collection through webservice c# - asp.net

Question

I am trying to return the results of monogdb query into a webapplication. The simplest initial one was just to return the full collection as you will see it in the mongodb console from a webservice call within the project that accesses the database:
> db.usercollection.find()
{ "_id" : ObjectId("52d2f2b3c60804b25bc5d2ca"), "username" : "testuser1", "email
" : "testuser1#testdomain.com" }
{ "_id" : ObjectId("52d2f2f9c60804b25bc5d2cb"), "username" : "testuser2", "email
" : "testuser2#testdomain.com" }
{ "_id" : ObjectId("52d2f2f9c60804b25bc5d2cc"), "username" : "testuser3", "email
" : "testuser3#testdomain.com" }
>
I would like to get the resulting json into an extjs grid. I am trying to ways to see if it works but the first question is actually how to return the result above:
<WebMethod()> _
<ScriptMethod(UseHttpGet:=True, ResponseFormat:=ResponseFormat.Json)> _
Public Function getDBData() As String
Dim response As String = String.Empty
mongo.Connect()
Dim db = mongo.GetDatabase("nodetest1")
Using mongo.RequestStart(db)
Dim collection = db.GetCollection(Of BsonDocument)("usercollection").FindAll()
response = collection.Collection.ToString
Return response
End Using
I am not seeing the result I want here:
var newStore = Ext.create('Ext.data.JsonStore', {
model: 'User',
proxy: {
type: 'ajax',
url: 'http://localhost:52856/WCFService/WebService1.asmx/getDBData',
reader: {
type: 'json',
root: 'd',
idProperty: '_id',
successProperty: 'success'
},
success: function (response, options) {
var s = response.responseText;
Ext.MessageBox.alert(s, 'LA LA LA');
newStore.loadData(s);
},
failure: function (response, options) {
Ext.MessageBox.alert('FAILED AGAIN', 'SUCKS');
}
}
});
I tried adding the root as follows:
response = "{""d"":" + response + "}"
Return response
The second alternative is to call the service from node.js directly but not show how to set up the result also:
Ext.Ajax.request({
url: 'http://localhost:3000/userlist',
method: 'GET',
success: function (response, options) {
var s = response.responseText;
Ext.MessageBox.alert(s, 'WOO WOO');
myStore.loadData(s);
},
failure: function (response, options) {
Ext.MessageBox.alert('FAILED MOFO', 'Unable to GET');
}
});
This is what I get back:
nodetest1.usercollection
View: userlist
extends layout
block content
h1.
User List
u1
each user, i in userlist
li
a(href="mailto:#{user.email}")= user.username
default route:
exports.index = function(db) {
return function(req, res) {
var collection = db.get('usercollection');
collection.find({},{}, function(e,docs){
res.render('userlist', {
"userlist" : docs
});
});
};
};
am I way off here or can someone see what I am doing wrong.

Answer 1

A call to FindAll returns a MongoCursor.
A quick way to convert that to a JSON format would be:
Return collection.ToArray().ToJSON()
You could loop through each result using a technique like this:
For Each document in collection
' do something with each document
Next document
Depending on the size of the results, you may find that returning the response uses a lot of server memory and takes a substantial amount of time to transmit and process in JavaScript.
Also, for production code, I'd recommend that the connection to MongoDB be only created once. The connection is thread safe and reusable (and uses a connection pool to support multiple clients). Opening and closing connections is "expensive."