I created a service called AppService.
Its function getUserPostionOptions is supposed to return an object:
getUserPostionOptions: function (user) {
// PositionOptions.findOne({id:'53f218deed17760200778cfe'}).exec(function (err, positionOptions) {
var positionDirectionsOptions = [1,2,3];
var positionLengthsOptions = [4,5,6];
var object = {
directions:positionDirectionsOptions,
lengths:positionLengthsOptions
};
return object;
// });
}
This works, in my controller positionOptions gets populated correctly:
var positionOptions = AppService.getUserPostionOptions(user);
However, when I uncomment the find query the item is found but the object returns undefined.
Thank in advance for your help
SailsJs ORM (and almost NodeJs database querying methods) uses non-blocking mechanism via callback function. So you have to change your code into:
getUserPostionOptions: function (user, callback) {
PositionOptions.findOne({id:'53f218deed17760200778cfe'}).exec(function (err, positionOptions) {
var positionDirectionsOptions = [1,2,3];
var positionLengthsOptions = [4,5,6];
var object = {
directions:positionDirectionsOptions,
lengths:positionLengthsOptions
};
callback(null, object); // null indicates that your method has no error
});
}
Then just use it:
AppService.getUserPostionOptions(user, function(err, options) {
if (!err) {
sails.log.info("Here is your received data:");
sails.log.info(options);
}
});
Related
I have a large aggrogate query that required me to pass "allowDiskUse: true" as an option. This would not work with the aggegate as described here:
https://github.com/meteorhacks/meteor-aggregate/issues/11
My meteor method is defined here. When I call the method I need to wait for ondata to complete before anything is returned to the client, but nothing I try allows me to get that data in a safe way up to the front end.
Meteor.methods({
'getSummary': function (dept,startDate,endDate,filterType) {
f = myQuery(startdate,enddate,dayFinalGroup);
f.on("data", Meteor.bindEnvironment(function(row) {
//load an array or something here to return
}));
f.once("end", Meteor.bindEnvironment(function() {
// tidy up, in my case end the stream
}));
//here I'd return the array loaded
},
});
This is my front end.
Meteor.call(
'getSummary',0,Session.get('start_date'),Session.get('end_date'),1,
function(error, result){
if(error){
console.log(error);
} else {
Session.set('sumTotals',result);
}
}
);
Finally Got it. I utilized wrapSync
'getSummary': function (dept,startDate,endDate,filterType) {
console.log(dept);
console.log(startDate);
console.log(endDate);
console.log(filterType);
var startdate = new Date(startDate);
var enddate = new Date(endDate);
var arr = [];
f = myQuery(startdate,enddate,dayFinalGroup);
var fetchCursor = Meteor.wrapAsync(function fetchCursor (cursor, cb) {
cursor.each(function (err, doc) {
if (err) return cb(err);
if (!doc) return cb(null, { done: true }); // no more documents
arr.push(doc);
});
});
var myData = fetchCursor(f);
return arr;
I'm trying to create a list with endless scroll in angularjs. For this I need to fetch new data from an api and then append it to the existing results of a scope in angularjs. I have tried several methods, but none of them worked so far.
Currently this is my controller:
userControllers.controller('userListCtrl', ['$scope', 'User',
function($scope, User) {
$scope.users = User.query();
$scope.$watch('users');
$scope.orderProp = 'name';
window.addEventListener('scroll', function(event) {
if (document.body.offsetHeight < window.scrollY +
document.documentElement.clientHeight + 300) {
var promise = user.query();
$scope.users = $scope.users.concat(promise);
}
}, false);
}
]);
And this is my service:
userServices.factory('User', ['$resource',
function($resource) {
return $resource('api/users', {}, {
query: {
method: 'GET',
isArray: true
}
});
}
]);
How do I append new results to the scope instead of replacing the old ones?
I think you may need to use $scope.apply()
When the promise returns, because it isnt
Part of the angular execution loop.
Try something like:
User.query().then(function(){
$scope.apply(function(result){
// concat new users
});
});
The following code did the trick:
$scope.fetch = function() {
// Use User.query().$promise.then(...) to parse the results
User.query().$promise.then(function(result) {
for(var i in result) {
// There is more data in the result than just the users, so check types.
if(result[i] instanceof User) {
// Never concat and set the results, just append them.
$scope.users.push(result[i]);
}
}
});
};
window.addEventListener('scroll', function(event) {
if (document.body.offsetHeight < window.scrollY +
document.documentElement.clientHeight + 300) {
$scope.fetch();
}
}, false);
Is it possible to create new Meteor collections on-the-fly? I'd like to create foo_bar or bar_bar depending on some pathname which should be a global variable I suppose (so I can access it throughout my whole application).
Something like:
var prefix = window.location.pathname.replace(/^\/([^\/]*).*$/, '$1');
var Bar = new Meteor.Collection(prefix+'_bar');
The thing here is that I should get my prefix variable from URL, so if i declare it outside of if (Meteor.isClient) I get an error: ReferenceError: window is not defined. Is it possible to do something like that at all?
Edit : Using the first iteration of Akshats answer my project js : http://pastie.org/6411287
I'm not entirely certain this will work:
You need it in two pieces, the first to load collections you've set up before (on both the client and server)
var collections = {};
var mysettings = new Meteor.Collection('settings') //use your settings
//Startup
Collectionlist = mysettings.find({type:'collection'});
Collectionlist.forEach(function(doc) {
collections[doc.name] = new Meteor.Collection(doc.name);
})'
And you need a bit to add the collections on the server:
Meteor.methods({
'create_server_col' : function(collectionname) {
mysettings.insert({type:'collection', name: collectionname});
newcollections[collectionname] = new Collection(collectionname);
return true;
}
});
And you need to create them on the client:
//Create the collection:
Meteor.call('create_server_col', 'My New Collection Name', function(err,result) {
if(result) {
alert("Collection made");
}
else
{
console.log(err);
}
}
Again, this is all untested so I'm just giving it a shot hopefully it works.
EDIT
Perhaps the below should work, I've added a couple of checks to see if the collection exists first. Please could you run meteor reset before you use it to sort bugs from the code above:
var collections = {};
var mysettings = new Meteor.Collection('settings')
if (Meteor.isClient) {
Meteor.startup(function() {
Collectionlist = mysettings.find({type:'collection'});
Collectionlist.forEach(function(doc) {
eval("var "+doc.name+" = new Meteor.Collection("+doc.name+"));
});
});
Template.hello.greeting = function () {
return "Welcome to testColl.";
};
var collectionname=prompt("Enter a collection name to create:","collection name")
create_collection(collectionname);
function create_collection(name) {
Meteor.call('create_server_col', 'tempcoll', function(err,result) {
if(!err) {
if(result) {
//make sure name is safe
eval("var "+name+" = new Meteor.Collection('"+name+"'));
alert("Collection made");
console.log(result);
console.log(collections);
} else {
alert("This collection already exists");
}
}
else
{
alert("Error see console");
console.log(err);
}
});
}
}
if (Meteor.isServer) {
Meteor.startup(function () {
// code to run on server at startup
Collectionlist = mysettings.find({type:'collection'});
Collectionlist.forEach(function(doc) {
collections[doc.name] = new Meteor.Collection(doc.name);
});
});
Meteor.methods({
'create_server_col' : function(collectionname) {
if(!mysettings.findOne({type:'collection', name: collectionname})) {
mysettings.insert({type:'collection', name: collectionname});
collections[collectionname] = new Meteor.Collection(collectionname);
return true;
}
else
{
return false; //Collection already exists
}
}
});
}
Also make sure your names are javascript escaped.
Things got much easier:
var db = MongoInternals.defaultRemoteCollectionDriver().mongo.db;
db.createCollection("COLLECTION_NAME", (err, res) => {
console.log(res);
});
Run this in your server method.
Scenario: I am trying to call a webservice which returns the results in json, the logic should be very straight forward.
I call a webservice url in WinJS.xhr() add a then function to process the result, here i am trying to bind it to a list.
I am using the below but i am not getting anything displayed what am i doing wrong here?
Can some one tell me how to call a winjs.xhr() from a function and return some object which i can bind as i am trying below?
function getData() {
return WinJS.xhr({ url: "http://search.twitter.com/search.json?q=%23windows8&rpp=10" })
}
function myFunc() {
getData().then(function (xhr) {
var jsondata = JSON.parse(xhr.responseText)
return jsondata;
// ...do something with the data when it arrives...
}, function (err) {
// ...do something with the error
});
}
var dataList = new WinJS.Binding.List(myFunc());
//var dataList = new WinJS.Binding.List(dataArray);
var publicMembers =
{
itemList: dataList
};
WinJS.Namespace.define("DataExample", publicMembers);
The ctor for WinJS.Binding.List accepts a list or array as the initial contents of the list. Your myFunc() will return nothing. You can set up an empty list using
var dataList = new WinJS.Binding.List()
and export it as you currently do.
Then, in myFunc(), placed below the dataList declaration, you can just add items to the list. For example, assuming that jsondata parses into an array:
function myFunc() {
getData().then(function (xhr) {
var jsondata = JSON.parse(xhr.responseText)
jsondata.forEach(function(entry) { dataList.push(entry); });
}, function (err) {
// ...do something with the error
});
}
Edit: I also assume you have bound dataList.dataSource to the itemDataSource of a WinJS.UI.ListView and set a matching itemTemplate property or render function.
How do I manage batch save in Mongoose? I saw it may not be possible yet:
How can I save multiple documents concurrently in Mongoose/Node.js?
Theres some mention about using some flow control library like q, but I also notice there promises in mongoose, can it be used? Can I do like in jQuery Deferred/Promises
$.when(obj1.save(), obj2.save(), obj3.save()).then ->
# do something?
Yes, you can do this with promises. If you were using the Q promise library, you could re-write #matz3's code like:
var tasks = [];
for (var i=0; i < docs.length; i++) {
tasks.push(docs[i].save());
}
Q.all(tasks)
.then(function(results) {
console.log(results);
}, function (err) {
console.log(err);
});
We start all the operations one at a time in the loop, but we don't wait for any of them to complete, so they run in parallel. We add a promise (that acts like a placeholder for the result) to an array. We then wait for all the promises in the array of promises to complete.
Most good Promises/A+ compatible libraries have some equivalent to Q.all
mongoose now allows you to choose which Promise implementation.
Here I am using the node.js default system Promise (ES6) baked into nodejs
var mongoose = require('mongoose');
mongoose.Promise = global.Promise; // use system implementation
Promise.all(obj1.save(), obj2.save(), obj3.save())
.then(function(resultSaves) {
console.log('parallel promise save result :');
console.log(resultSaves);
mongoose.disconnect();
}).catch(function(err) {
console.log('ERROR on promise save :');
console.log(err);
mongoose.disconnect();
});
node --version
v4.1.1
mongoose#4.1.8
Since mongoose now supports promises you may use Promise.all().then(), so it will return when all promises are resolved.
Promise.all([
obj1.save(),
obj2.save(),
obj3.save()
])
.then(console.log)
.catch(console.error)
In fact, if you're always calling the save() method you can use the Array.map() here:
Promise.all([ obj1, obj2, obj3 ].map( obj => obj.save() )
Aaand also use es6 syntax to destructure the resulting array:
Promise.all(
[ obj1, obj2, obj3 ]
.map( obj => obj.save() )
)
.then( ([ savedObj1, savedObj2, savedObj3 ]) => {
// do something with your saved objects...
})
Try the parallel function of the async module.
var functions = [];
for (var i=0; i < docs.length; i++) {
functions.push((function(doc) {
return function(callback) {
doc.save(callback);
};
})(docs[i]));
}
async.parallel(functions, function(err, results) {
console.log(err);
console.log(results);
});
To save multiple mongoose docs in parallel, you can do something simple like this (assuming you have an array named docs of documents to save):
var count = docs.length;
docs.forEach(function(doc) {
doc.save(function(err, result) {
if (--count === 0) {
// All done; call containing function's callback
return callback();
}
});
});
A refined example on how to use async parallel would be:
async.parallel([obj1.save, obj2.save, obj3.save], callback);
Since the convention is the same in Mongoose as in async (err, callback) you don't need to wrap them in your own callbacks, just add your save calls in an array and you will get a callback when all is finished.
What about async.queue.
A simple example:
var queue = async.queue(function(obj, callback) {
return obj.save(callback);
});
for (var i in objs) {
var obj = objs[i];
// Some changes on object obj
queue.push(obj);
}
If you need a callback after the queue is emptied:
var emptyQueue = true;
var queue = async.queue(function(obj, callback) {
return obj.save(callback);
});
queue.drain = function() {
// Every callbacks are finished
// bigCallback();
};
for (var i in objs) {
var obj = objs[i];
// Some changes on object obj
queue.push(obj);
emptyQueue = false;
}
if (emptyQueue) {
// Call manually queue drain in case of the queue is empty
// and we need to call bigCallback() for example
return queue.drain();
}
#ForbesLindesay Why loading an external library when you can use mongoose implementation of promises and create your own All ?
Create a module that enhance mongoose promise with all.
var Promise = require("mongoose").Promise;
Promise.all = function(promises) {
var mainPromise = new Promise();
if (promises.lenght == 0) {
mainPromise.resolve(null, promises);
}
var pending = 0;
promises.forEach(function(p, i) {
pending++;
p.then(function(val) {
promises[i] = val;
if (--pending === 0) {
mainPromise.resolve(null, promises);
}
}, function(err) {
mainPromise.reject(err);
});
});
return mainPromise;
}
module.exports = Promise;
Then use it with mongoose:
require('./promise')
...
var tasks = [];
for (var i=0; i < docs.length; i++) {
tasks.push(docs[i].save());
}
mongoose.Promise.all(tasks)
.then(function(results) {
console.log(results);
}, function (err) {
console.log(err);
});