Relational Query in Parse - parse-platform

I have 4 classes in Parse. I am using JavaScript.
1) Rangoli - Main item objects
2) Categories - List of all categories
3) Users - List of all users
4) ItemCategories - List of categories that each items are assigned
Below is the structure of all classes.
Now I am trying to get the following details in a single query.
1) User - Name, email, avatar
2) Rangoli - filename, createdAt
3) Categories - name
This is the JavaScript code that I tried.
var Rangoli = Parse.Object.extend("Rangoli");
var ItemCategories = Parse.Object.extend("ItemCategories");
var query = new Parse.Query(ItemCategories);
var innerQuery = new Parse.Query(Rangoli);
innerQuery.matchesQuery("category", query);
query.find({
success : function (data) {
console.log(JSON.stringify(data));
},
error : function (e) {
}
});
With the above JavaScript code, I am getting the record of ItemCategories record and not all the columns of all pointer class like Categories, User, Rangoli.

You can include related objects in the results of a query by using the include method. e.g.
var ItemCategories = Parse.Object.extend("ItemCategories");
var query = new Parse.Query(ItemCategories);
query.include("item");
query.include("category");
You can also use this to get objects nested at multiple levels, e.g., query.include(["category.rangoli"]); but from your data model screenshot I can't see a way to include the Rangoli data with the relationships you have set up.

Related

sys_id arrays to is one of not displaying records on my report

I am not able to display records on my report.
Report Source: Group Approval(sysapproval_group) table
Condition:Sys Id - is one of - javascript: new GetMyGroupApprovals().getSysIds();
Script Include : MyGroupApproval
Note : Active is checked, Accesible is all application score & Client callable unchecked
var GetMyGroupApprovals = Class.create();
GetMyGroupApprovals.prototype = {
initialize: function() {
},
getSysIds : function getMyGroupMembers(){
var ga = new GlideRecord('sysapproval_group');
ga.addQuery('parent.sys_class_name', '=', 'change_request');
ga.query();
gs.log("TotalRecords1 Before:: " + ga.getRowCount());
var sysIdArray = [];
while(ga.next()){
sysIdArray.push(ga.sys_id);
}
return sysIdArray;
},
type: 'GetMyGroupApprovals'
};
Kindly note that I have to achieve with script approach. I am not able to get records on my report.
This line is probably causing unexpected behavior:
sysIdArray.push(ga.sys_id);
ga.sys_id returns a GlideElement object, which changes for each of the iterations in the GlideRecord, so the contents of sysIdArray will just be an instance of the same object for each row in the result set, but the value will just be the last row in the set.
You need to make sure you push a string to the array by using one of the following methods:
sysIdArray.push(ga.sys_id+''); // implicitly call toString
sysIdArray.push(ga.getValue('sys_id')); // return string value
Quick suggestion, you can use the following to get sys_ids as well:
sysIdArray.push(ga.getUniqueValue());

RethinkDB Thinky - rows within 1 hour

r.db('dbname').table('urls').filter(function(url) {
return url("expires_at").date().eq(r.now().date())
.and(url("expires_at").hours().eq(r.now().hours().sub(1)))
});
I am trying to write the equivalent query using thinky ORM for node.js
I've never worked with Thinky, but according to docs, you should create model and make query on it.
1) Create model. I don't know what documents you are storing in Rethink. But something like this:
var thinky = require('thinky')();
var type = thinky.type;
// Create a model
var Urls = thinky.createModel("urls", {
id: String,
expires_at: Date
// another fields if needed
});
2) Query:
Don't know actual syntaxes for filter in Thinky, but somehting like this:
Urls.filter(function(url) {
return url("expires_at").date().eq(r.now().date())
.and(url("expires_at").hours().eq(r.now().hours().sub(1)))
}).then(function(result) {
// result is an array of instances of `Urls `
});

Find objects not in a relation

I have a custom object Team in Parse with a relation field for the default User object. What I would like to do is retrieve all User objects which are not related to any Team object. Can anyone point me in the right direction on how to do this using the JavaScript SDK? I've been going over the documentation for the Query object but I can't find anything.
Perhaps another type of relation, or placing the relation at another place is a better solution. What I want to accomplish is the following: Each user is allowed to be in one team and one team only. In addition I need to be able to query the following information from Parse:
I want to retrieve the User objects of all the users assigned to a team
I want to retrieve the User objects of all the users who are not assigned to any team
I have tried using a join table with both the user and team object ids. Then I tried to following query to get all users not assigned to a team:
var teammember = Parse.Object.extend('TeamMember'),
query = new Parse.Query("User");
var innerQuery = new Parse.Query("TeamMember");
query.doesNotMatchQuery('user', innerQuery);
query.find({
success: function(results) {
response.success(results);
},
error : function(error) {
response.error(error);
}
})
But this just gets me the following response: error: "{"code":102,"message":"bad type for $notInQuery"}".
I like the Relation type as I can add or remove multiple members at once with a single call to the REST API. I also have no problems retrieving the information on team members when using the Relation type to connect the users to the teams. It is just getting the users which are not assigned to any team that is giving me problems.
It doesn't sound like you need a relation at all. Instead, add a Pointer column to User that points to Team. It ensures that a User can only belong to one team, and your other requirements can be captured as follows.
// All users assigned to a team
query = new Parse.Query('User');
query.exists('team');
// All users assigned to a specific team
query = new Parse.Query('User');
query.equalTo('team', specificTeam);
// All unassigned users
query = new Parse.Query('User');
query.doesNotExist('team');
Update: If you need to support multiple teams per User in the future, then I would suggest creating a Parse table called Membership with two columns: a Pointer to User and a Pointer to Team. This essentially gives you more control than relying on Parse relations, but it gets a little more complicated.
_ = require('underscore'); // Or lodash
// All users assigned to a team
query = new Parse.Query('Membership');
query.find().then(function (results) {
// http://underscorejs.org/#uniq
users = _.uniq(results, false, function (user) { return user.id; });
});
// All users assigned to a specific team
query = new Parse.Query('Membership');
query.equalTo('team', specificTeam);
// All unassigned users
var assignedUsers = []
var unassignedUsers = []
memberQuery = new Parse.Query('Membership');
userQuery = new Parse.Query('User');
memberQuery.find().then(function (memberResults) {
// http://underscorejs.org/#map
var ids = _.map(memberResults, function (user) { return user.id; });
// http://underscore.js.org/#uniq
assignedUsers = _.uniq(ids);
userQuery.find();
}).then(function (userResults) {
var users = _.map(userResults, function (user) { return user.id; });
// http://underscorejs.org/#difference
unassignedUsers = _.difference(users, assignedUsers);
});
To add and remove Users to/from Teams, you would create Membership objects and save API calls with Parse.Object.saveAll() and Parse.Object.destroyAll().
I ran into trouble with the answer provided by Seth. When retrieving the users not assigned to a team the difference between the two arrays would be incorrect. I am assuming this is due to the assignedUsers having object of type Membership and userResults being of type User. This would make it impossible for underscore to make a proper match.
I would up using this as my Cloud Code:
Parse.Cloud.define("getTeamlessUsers", function(request, response) {
var _ = require("underscore"),
assignedUsers = [],
companyUsers = [],
memberQuery = new Parse.Query("TeamMembers"),
userQuery = new Parse.Query("User"),
index,
ubound;
memberQuery.find().then(function(memberResults) {
// Make sure each User ID will appear just once
memberResults = _.unique(memberResults, false, function(item) { return item.get('user').id; });
// Loop over the unique team members and push the User ID into the array
for (index = 0, ubound = memberResults.length; index < ubound; index++) {
var user = memberResults[index].get("user");
assignedUsers.push(user.id);
}
// Get al the users
return userQuery.find();
}).then(function(userResults) {
// Loop over all the users and push the ID into the array
for (index = 0, ubound = userResults.length; index < ubound; index++) {
companyUsers.push(userResults[index].id);
}
// Create an array of user IDs which are not present in the assignedUsers array
var result = _.difference(companyUsers, assignedUsers);
// Return the IDs of user not assigned to any team
response.success(result);
}).fail(function(error) {
response.error(error);
});
});

Backbone, rest, populate collection

I'm trying to do my first webapp with backbone/mvc3 and i would like to have some advices to populate a collection.
Here is a part of my collection
window.TaskList = Backbone.Collection.extend({
model: Task,
url: "../../api/Tasks";
},.......
I can use the crud methods to get/update the models but i've the following problem :
When i open the page, my collection is populated (calling the get method serverside) But i would like to have this kind of behavior :
Page 1 : put/delete/get methods => as usual but the collection has to be populated calling the getTasksByWorkshopId serverside method
Page 2 : put/delete/get methods => as usual but the collection has to be populated calling another serverside method to filter the list
...
(ie : i cant filter the collection client side because of the amount of data)
So, my question is : how to keep a generic collection url (as api/Tasks) and populate the collection with another method (do i have to override smth ?)
(sorry for this newbie question)
Thanks in advance
In a comment to the other answer you said that "When the collection is loaded, the url called is /api/Tasks/Workshop/1 (the good one) but, when i want to update a task, the url called is /api/Tasks/Workshop/1/141 instead of /api/Tasks/141."
In order to "update a task" (a task model, I assume) to a different URL, then your Collection & Model should have different URLs. If you define a collection without specifying the model property, the URL used when saving/fetching/deleting a model will be based off of the collection's URL. The same is also true if the collection's model has no defined url property. See below.
Also, JSFiddle example here.
var WorkshopModel = Backbone.Model.extend({
urlRoot: "api/tasks/"
});
var WorkshopCollection = Backbone.Collection.extend({
model: WorkshopModel,
urlRoot: "api/tasks/workshop",
url: function() { return this.urlRoot + '/' + this.id; },
initialize: function(models, options) {
this.id = options.id;
}
});
var c = new WorkshopCollection(null, { id: 1 });
c.fetch(); // GET => api/tasks/workshop/1
var m = c.add({ id: 300, color: 'red' });
m.save(); // PUT => api/tasks/300
m.destroy(); // DELETE => api/tasks/300
m.fetch(); // GET => api/tasks/300
If you remove the urlRoot property from the WorkshopModel, then the URL that the models use will be the collection.url() + '/' + model.id ( api/tasks/workshop/1/300 )
You can do like this :
window.TaskList = Backbone.Collection.extend({
model: Task,
urlRoot: "../../api/Tasks",
url: function() {
if (/*page 1*/) { // you can access this.options where you can pass parameters to distinct the 2 services, when calling the fetch function
return this.urlRoot + // getTasksByWorkshopId URL ;
} else {
return this.urlRoot + // the other service URL ;
}
} ...
}

How do you model form changes under Spring MVC?

Say you're writing a web page for fruit vendors using Spring MVC's SimpleFormController, version 2.5.6. On this page the vendor can do simple things like change their name or their address. They can also change their inventory based on a drop down list filled with present inventory selections.
When this drop down list selection changes, the entire form changes to match the inventory of what has been selected. So one stock selection may have bananas and pears, another may have melons, blueberries and grapefruit.
Inside each inventory selection is a input field that needs to be propagated back to the database, for the sake of this example let's say that the user enters the number of fruit.
The way this is modeled in the database is that each Stock name is stored in a table, which has a one to many relationship with the contents of each stock, which would be the type of fruit in this example. Then the type of fruit has a one to many relationship with the quantity the vendor selects. Stock name and the type of fruit in each stock are stored in the database and are unchangeable by the user, with the connected fruit quantity table being editable.
My question is, how do you model the form described above in Spring MVC?
I've tried overriding the isFormChangeRequest and onFormChange to facilitate the form change, but I think I may be misunderstanding the intent of these methods. When I change my backing command object the next time the page is post it tries to bind the request into the form, which breaks if you adjust the size of the Stock array (say from 3 to 2, it will try and bind into the 3rd value, even if it is empty).
If you have a limited amount of different stocks, you can use different handler mappings for each one with a different backing model:
#RequestMapping(params="stock=example1")
ModelAndView handleExample1(#ModelAttribute("stock") ApplesOrangesPears stockObject)
#RequestMapping(params="stock=example2")
ModelAndView handleExample2(#ModelAttribute("stock") BananasPotatos stockObject)
But I guess that is not the case, there are a lot of different stock types and they are dynamic. In that case you can register custom property editor (#InitBinder), and determine dynamically the actual type of the backing object for the inventory, then validate, and convert to or from it explicitly.
What I ended up doing is firing a JavaScript event when the selection in the drop down is changed. This JavaScript (seen below) generates a URL based on the selection of the drop down and uses a location.replace to go to the new URL, which causes the controller to generate a new form.
Using this method over overriding the isFormChangeRequest and onFormChange has allowed me to avoid binding errors caused by left over post data.
function changeUrl(selectionValue) {
var param = getParams();
param["dropdownselection"] = selectionValue;
window.location.replace(getBaseUrl() + buildQueryString(param));
}
//taken from http://javascript.about.com/library/blqs1.htm
function getParams() {
var qsParm = new Array();
var query = window.location.search.substring(1);
var parms = query.split('&');
for (var i = 0; i < parms.length; i++) {
var pos = parms[i].indexOf('=');
if (pos > 0) {
var key = parms[i].substring(0,pos);
var val = parms[i].substring(pos+1);
qsParm[key] = val;
}
}
return qsParm;
}
function getBaseUrl() {
var url = document.location.toString();
if (url.indexOf('?') != -1) {
url = url.substring(0, url.indexOf('?'));
}
return url;
}
function buildQueryString(param) {
var queryString = "?";
for (var key in param) {
queryString += key + "=" + param[key] + "&";
}
//remove last "&"
return queryString.substring(0,queryString.length - 1);
}

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