Get Data from parse.com Promises - parse-platform

Question

I am trying to use parse.com promises to retrieve job data as well as user relation data associated with the job. I have a function that returns promises but not job data. How do I get the job & employee information from the returned promises?
Logically I want to:
1) Query Parse to get array of jobs
2) For each job, query Parse again to get the employee relation information
3) Create local object that contains job & employee details
4) Add each job object to local array
5) Load table with array of objects once all information has been retrieved from Parse
I can do steps 1-4 but I can't figure out how to wait until all information has been retrieved from Parse to refresh the local table.
function getJobPromises (){
var promises = [];
var Job = Parse.Object.extend("Job");
var query = new Parse.Query(Job);
query.equalTo("company", company);
query.notEqualTo("isDeleted", true);
query.limit(1000); // raise limit to max amount
query.find().then(function(results) {
// Create a trivial resolved promise as a base case.
var promise = Parse.Promise.as();
_.each(results, function(result) {
// For each item, extend the promise with a function to add it to the job array
promise = promise.then(function() {
// Return a promise that will be resolved when the job details have been added to the array
var object = result;
promises.push(getEmployeeName(object));
allJobDataArray = promises;
});
});
return Parse.Promise.when(promises);
}).then(function() {
// Every job has been retrieved
console.log("All items have been returned. Refresh table...");
console.log(allJobDataArray);
});
}
The function that does the relational query to get the users associated with the job
function getEmployeeName(jobObject) {
var employeeNameArray = [];
//Query to get array of employees for the passed in job
var rQuery = jobObject.relation("employee");
return rQuery.query().find({
success: function(employees){
//Get employees full name for each job
for (var i = 0; i < employees.length; i++) {
var objEmployee = employees[i];
var fullName = objEmployee.get("fullName");
employeeNameArray.push(fullName);
console.log(employeeNameArray);
}
},
error: function(error){
response.error(error);
}
});
}
Update
It is now working thanks to #eduardo
I have a public array to hold the job objects.
var jobObjectsArray = [];
In the getEmployeeName function I am creating the job objects and adding them to that array
function getJobPromises (){
var promises = [];
var Job = Parse.Object.extend("Job");
var query = new Parse.Query(Job);
query.equalTo("company", company);
query.notEqualTo("isDeleted", true);
query.limit(1000); // raise limit to max amount
query.find().then(function(results) {
_.each(results, function(result) {
promises.push(getEmployeeName(result));
});
return Parse.Promise.when(promises);
}).then(function(allJobDataArray) {
// allJobDataArray should be actually an Array of Array
console.log(jobObjectsArray);
refreshTable();
});
}
function getEmployeeName(jobObject) {
var employeeNameArray = [];
//Query to get array of employees for the passed in job
var rQuery = jobObject.relation("employee");
return new Promise(
function(resolve, reject) {
rQuery.query().find({
success: function(employees){
//Get employees full name for each job
for (var i = 0; i < employees.length; i++) {
var objEmployee = employees[i];
var fullName = objEmployee.get("fullName");
employeeNameArray.push(fullName);
var objAllJobs = new Object();
objAllJobs["jobId"] = jobObject.id;
objAllJobs["location"] = jobObject.get("location");
objAllJobs["startTime"] = jobObject.get("startTime");
objAllJobs["employee"] = employeeNameArray;
jobObjectsArray.push(objAllJobs);
}
console.log(employeeNameArray);
resolve(employeeNameArray);
},
error: function(error){
reject(error);
}
});
}
);

Answer 1

There was a few incorrect uses of the promise concept. I will go through them, but first here is the final code:
function getJobPromises (){
var promises = [];
var Job = Parse.Object.extend("Job");
var query = new Parse.Query(Job);
query.equalTo("company", company);
query.notEqualTo("isDeleted", true);
query.limit(1000); // raise limit to max amount
query.find().then(function(results) {
_.each(results, function(result) {
promises.push(getEmployeeName(result));
});
return Parse.Promise.when(promises);
}).then(function(allJobDataArray) {
// allJobDataArray should be actually an Array of Array
console.dir(allJobDataArray);
console.log(allJobDataArray[0]);
});
}
function getEmployeeName(jobObject) {
var employeeNameArray = [];
//Query to get array of employees for the passed in job
var rQuery = jobObject.relation("employee");
return rQuery.query().find({
success: function(employees){
//Get employees full name for each job
for (var i = 0; i < employees.length; i++) {
var objEmployee = employees[i];
var fullName = objEmployee.get("fullName");
employeeNameArray.push(fullName);
}
console.log(employeeNameArray);
return employeeNameArray;
},
error: function(error){
response.error(error);
}
});
}
"Parse.Promise.as()" should be used only if you have a value that you want to return as a promise. Something like:
Parse.Promise.as("my value").then(function(foo) {
console.log(foo) // "my value"
});
So if your "getEmployeeName" function is returning a promise, which means that this "rQuery.query().find" returns a promise, you don't have to create a new promise or use the "Parse.Promise.as()", it is already a promise and you can push it to the promises array.
Another problem was that you were not return anything in the "getEmployeeName" method callback. Take a look into my version, I'm returning "employeeNameArray".
My version will only work if this "rQuery.query().find" method returns a promise. If that is not the case, you can create a new promise using its callbacks like this:
function getEmployeeName(jobObject) {
var employeeNameArray = [];
//Query to get array of employees for the passed in job
var rQuery = jobObject.relation("employee");
return new Promise(
function(resolve, reject) {
rQuery.query().find({
success: function(employees){
//Get employees full name for each job
for (var i = 0; i < employees.length; i++) {
var objEmployee = employees[i];
var fullName = objEmployee.get("fullName");
employeeNameArray.push(fullName);
}
console.log(employeeNameArray);
resolve(employeeNameArray);
},
error: function(error){
reject(error);
}
});
}
);
}
Please notice this "new Promise()" depends on the browser support of Promise, I don't know if Parse has an equivalent. Anyways you can use it with a polyfill that implements the necessary code if the browser has no support.
More about standard promises: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise
Polyfill: https://github.com/jakearchibald/es6-promise/
Hope this helps.